Model Engine Maker

General Category => Oddball => Topic started by: kvom on November 15, 2017, 05:45:38 PM

Title: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 15, 2017, 05:45:38 PM
I decided that after cogitating on this project for 2 years, I'd better commit to an actual build in 2018.  What better way to commit than to invest $170+ at McMaster in the various pieces needed to put together the parts I need to machine.

For those unfamiliar with this model look here:  http://www.modelenginemaker.com/index.php/topic,5404.0.html

Rather than plywood this build will be aluminum for structural parts primarily, with some acrylic a possibility for some parts.  The aluminum parts in many cases won't be as thick as the wooden prototype, but to maintain the overall width of the model spacers will be needed to align them.  I plan to modify the Solidworks model I did using the original dimensions in order to verify fits.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIC
Post by: b.lindsey on November 15, 2017, 06:14:26 PM
Great, I will be looking forward to it. I have looked up the individual prices for the McMaster items (excluding the wood) but hadn't added them all up yet. Not very surprised at your total though...no worse that a casting set for an engine though :)

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIC
Post by: Vixen on November 15, 2017, 08:33:11 PM
Hello Kvom,

You are going to enjoy making your Colibri come to life. As you know, I built my version entirely out of tinted acrylic sheet (perspex, plexiglass) at a reduced size of 40%.

You do not need any fancy gear cutters to produce the core mechanism. I used a 3mm end mill to profile all the gears. Derek Hugger makes generous allowances in his design to fret saw them from wood. They are a rattling good fit and everything moves freely with very little fetling required. The bird is similarly straightforward to make, there are many, many pieces. The four link mechanism to articulate the wings needs plenty of attention to reduce binding and friction so that the wings beat smoothly. A bigger and heavier bird (mine is only 40% size) will help considerably.

Enjoy your build and please keep us posted with plenty of photos

Mike

(http://i901.photobucket.com/albums/ac218/v8vixen1/P1050468.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIC
Post by: Dreeves on November 16, 2017, 02:23:26 AM
Looking forward to following along.

Dave
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 16, 2017, 05:02:49 PM
Considering materials, one issue I foresee is with the hypocycloidal gears are in contact with the frame across their entire surface.  They have a mean diameter of 4.3".  They can't be made of aluminum as galling could occur against the aluminum frame.  I originally drew them as brass in SW, but stock for making 3 of these would be well over $120.  I considered PTFE and Delrin, but here the material would be about $45 each.  Since these parts are quite hidden by the cams I decided to have one printed in a hard nylon by Shapeways for $25.  I'll see how the friction is before deciding whether to order two more.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 16, 2017, 05:06:56 PM
I would like the gears to be brass, but again finding 6" round pieces 1/4" thick is problematic.  Again galling would be a problem with all aluminum.  My idea is for the center large gear to have an aluminum body with brass gear teeth attached, made in two pieces.  The other two large gears will be aluminum, and the two smaller pinion gears brass.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on November 16, 2017, 05:19:03 PM
How about grey PVC sheet, is that any better on price? I had gotten some 1/2" and 3/4" thick offcuts, machines quite well and the surface is quite smooth.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 16, 2017, 06:14:34 PM
That would be the cheapest material yet.  Worth a look see.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: awJCKDup on November 16, 2017, 11:19:58 PM
How about aluminum with an anodized coating?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 18, 2017, 07:56:00 PM
Made a test setup for a gear/hypocycloid/cam from some 1/4" 6061 and some 1/16" SS dowel pins.  I should get the hypocycloid gear from Shapeways early next week and can see how the friction is between the parts.  I don't foresee any problems, but I don't want to start on the frame components before checking.

(http://www.pbase.com/kvom/image/166592115/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 19, 2017, 10:46:07 PM
First part completed today.  Actually it's two parts, since the wooden version has two glued together since it doesn't use any 3/4" thick stock.  In any case I give you the tail pinion gear.

The gear has a diameter a bit less than 1.7".  I have several lengths of brass hex rod that's 1.875" across the sides, so I cut off a 2" piece, chucked in the lathe, and turned down a 1.125" spigot 1/4" deep.  This will allow the piece to be held in a 5C collet for further ops.

(http://www.pbase.com/kvom/image/166598245/large.jpg)

Next mount in the collet chuck and turn down to 1.75" diameter for a length of 1".  The pinion will rotate on a 1/8" axis, so a hole of that diameter is drilled.

(http://www.pbase.com/kvom/image/166598246/large.jpg)

I moved the work and collet to a collet block and the vise on the CNC mill.  The teeth were milled with 3/16" carbide endmill, the largest that would work.

(http://www.pbase.com/kvom/image/166598247/large.jpg)

Then back to the lathe to be parted off.

(http://www.pbase.com/kvom/image/166598248/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on November 19, 2017, 11:00:13 PM
That is a fine looking part Kirk. I am anxious to see how the 3D printed part comes out now.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 20, 2017, 10:23:18 PM
Couple of more parts today, again part of the tail assembly.The "fan" is actually two parts as I machined the standoff integral to it.

(http://www.pbase.com/kvom/image/166604364/large.jpg)

And then the rack.  Both it and the fan are actuated by the pinion gear from yesterday.

(http://www.pbase.com/kvom/image/166604368/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on November 20, 2017, 10:49:32 PM
 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on November 21, 2017, 12:34:18 AM
Kirk, are you using the dxf files provided with the plans?

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Flyboy Jim on November 21, 2017, 04:32:08 AM
Kirk,

 I'd love to see (as would others I bet) some pictures of these parts being made. Also some details about your CNC mill. These parts look great!  :ThumbsUp:

Jim
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 21, 2017, 01:47:58 PM
The original DXF files for the colibri consist of one large layout for each of the 4 thicknesses of plywood.  I extracted each part individually and used it to generate a Solidworks model.  Now I am regenerating the individual DXFs for fabrication from SW.

My mill is a Novakon NM200 that I purchased in 2010.  It has a 3HP spindle with a maximum speed of 4000 RPM and used R8 collets.  Up until recently the control was Mach3 using the parallel printer port to communicate with the breakout board.  Now I'm running Tormach's PathPilot control program that eliminates the parallel port and moves much of the low level operations from the CPU to a Mesa I/O board.  The motion is a bit smoother now.  Previously the maximum rapids were 75 inches per minute.  Now I could go a lot higher, but I'm just using 100 for now.  The user interface with PathPilot is a bit better as well requiring fewer mouse clicks for zeroing parts.

I've been using CamBam for g-code generation since the beginning.  PathPilot runs the same code as Mach3 without modification.  I typically will simulate parts using Cutviewer Mill software.  Doing so can detect unintended consequences, and also shows how long the machining will take.  On the fan part, I spend a good while tweaking the settings in CamBam to reduce the machine time.  Normally I use conservative feeds and speeds, but I don't want to overdo it and spend hours watching a part being machined.  I use GWizard for feed and speed calculations.

For model engines, there's typically many parts that get made on the manual mill.  The parts for colibri are almost all curved in some manner, so other than round spacers I expect most of the machining here will be done via CNC.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: bent on November 21, 2017, 06:26:05 PM
Watching with interest  :popcorn:.  We have a CO2 laser cutter at work which would work well for the plywood version of the 'bird (even better in acrylic sheet), but I'm not so interested as to want to spend that much...yet  ;).  Some of Mr. Derek Hugger's other design plans are less costly, though, and also intriguing:

http://www.derekhugger.com/colibri.html

(cut and pasted from the Youtube channel posted by the OP)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: simplyloco on November 21, 2017, 06:37:45 PM
We are driving down to Albir, Spain, in the New Year, having rented a nice bíg Spanish Villa for three months. There's plenty of room there for my new Excalibur saw, and I've dropped plenty of hints about Colibri plans for Christmas... :LittleAngel:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 21, 2017, 06:51:36 PM
I think with a laser cutter and wood I'd still use a drill for the holes.  But certainly having all the pieces cut in one go each from each thickness would result in a very fast build.  The same goes for using a large CNC router.

Manually cutting all the wood parts with a jigsaw sounds tedious to me.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 21, 2017, 11:38:49 PM
Today's part is called the 'tail mount right', or the support part of the tail mechanism on the bird's right hand side.  In this picture of the assembly it's the dark grey.

(http://www.pbase.com/kvom/image/166609394/medium.jpg)

The process to make this part has a number of steps, of which the first is to open its DXF file in CamBam and specify the machining operations to be applied:

(http://www.pbase.com/kvom/image/166609423/large.jpg)

In this case there are 9 operations as shown in the tree image to the left of the screen. The first 5 are for drilling the various holes.  Then there are roughing and finishing ops for the opening in the center, and finally a profile op on the outer boundary.  To check before cutting metal, I emulate with CutViewer.

(http://www.pbase.com/kvom/image/166609428/large.jpg)

The drawing tell me the part will fit inside a 4x4" square of aluminum, and it's specified as 3/8" thick.  Essentially all the parts in colibri are designed to be cut completely through sheet stock, so some means of holding it must be conceived for each.  Since there are 3 1/4" holes, my plan is to attach the stock to a base with screws.  First, I use some spray adhesive to attach it along with a small clamp.  The assembly is mounted in the vise at the mill with a stop on the fixed jaw.  This stop will allow me to remove the work after the drilling in order to apply the screws;  then it can be replaced in the vise in the same position.

(http://www.pbase.com/kvom/image/166609350/large.jpg)

For each drill bit and endmill I need to establish the top of the stock as the Z0 position.  PathPilot assumes one each tool is in a software table with a predefined length.  For this to work I'd need numerous tool holders.  Instead I measure each one at tool change using a 1" gauge block.  But I have to stop the program to do so, and then manually restart it afterwards.

(http://www.pbase.com/kvom/image/166609354/large.jpg)

The screen on the PathPilot control shows the toolpaths graphically.

(http://www.pbase.com/kvom/image/166609356/large.jpg)

With the stock screwed to its fixture we're ready to do the milling ops.

(http://www.pbase.com/kvom/image/166609359/large.jpg)

And the final result:

(http://www.pbase.com/kvom/image/166609363/large.jpg)

For parts that don't have convenient holes other methods of workholding will be used.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on November 21, 2017, 11:50:54 PM
That turned out well Kirk. Will be interesting how much weight you need to balance the entire mechanism when it's all out together.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Flyboy Jim on November 22, 2017, 03:08:24 AM
Good explanation Kirk. Thanks. I even kinda understood it!  :hammerbash: I can see where this CNC stuff would really open up some doors for projects like this. Actually...... I'm just now machining the rocker arm for my P & W build and it would be a great CNC project!

Jim
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 24, 2017, 09:42:36 PM
A few Thanksgiving parts.  The right side of the tail mount was combined so that the two standoffs are integral (i.e., equals 3 wood parts).

(http://www.pbase.com/kvom/image/166620809/large.jpg)

Then in order to combine all the parts made thus far I needed the central piece, called "tail feather mount" in the plans.  Material is Mic6 aluminum, 1/2" thick.  Holding tabs were used for the machining/

(http://www.pbase.com/kvom/image/166620810/large.jpg)

After separating, a 1/16" hole was needed for the tail feather pivot.

(http://www.pbase.com/kvom/image/166620811/large.jpg)

Now assembling the first two parts.  Note that with the wood version, the 5/32 tube and 2" wood screw are used to align the parts, which would be glued together.  Here we'll use loctite on the tube and a 2-56 screw.  I will avoid trying to glue metal faces if at all possible.

(http://www.pbase.com/kvom/image/166620812/large.jpg)

Seems my deburring needs some work.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on November 24, 2017, 09:57:24 PM
 A little 320 grit paper on a surface plate on those flat sides and they will look perfect !!  Nice idea integrating the parts into one piece as well.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: simplyloco on November 24, 2017, 10:49:41 PM
SNIP

Manually cutting all the wood parts with a jigsaw sounds tedious to me.

Watching a CNC centre take 4 thou cuts all day seems pretty tedious to me: I have the callouses on the palms of my hands to prove that I like moving machine handles! :insane:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 25, 2017, 12:42:40 AM
Further assembly requires accurate parting off of spacers from 9/32" brass tube with a 1/4" ID.  Ordered a 9/32 collet today along with a bunch of colored acrylic sheet for the body and flower.  Should arrive on Monday, along with the gear from Shapeways.  In the interim, more parts to machine.

The 316 SS tube used for the axes of the roller bearings is a bitch to tap (8-32).  I might use a larger drill for the next ones.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on November 26, 2017, 08:59:38 PM
I received the hypocycloid gear from Shapeways on Friday, so continuing with the "proof of concept" I cobbled together an eccentric cam from brass (throw is 0.4") to test the motion.  Here's a short video:

vSZ1F4ApuJU
Note that the hypocycloid turns in the opposite direction from the eccentric and makes 1 turn for every 4 of the eccentric.  For the sculpture the gear reduction is 1:2 so that the total reduction from the input crank is 8:1. 
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on November 26, 2017, 09:12:43 PM
Another one of those mesmerizing motions!   

 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 02, 2017, 01:23:53 AM
The "feathers" of the tail are five separate parts that use the rack and pin in slots to spread out as colibri flies.  They are to be made from 1/8" red acrylic.  I ordered a 12x12" piece from McMaster and cut it into 4 6x6s.  Two feathers fit on a single piece (closely).  Such thin stock is impossible to hold in the vise as it will just bend under the pressure of the jaws.  I came up with this "fixture".

(http://www.pbase.com/kvom/image/166657951/large.jpg)

The acrylic has paper covering on both sides that can be easily peeled off after machining.

Afterwards the two are still attached by holding tabs to the rest of the stock.  The tabs are easily clipped apart and the nubs sanded off.

(http://www.pbase.com/kvom/image/166657952/large.jpg)

I regret to say that some mishaps caused unintended breakage so that I have no more stock and only 4 good feathers.  The 5th must attend acquisition of another piece.

Colibri uses a number of SS tubes that attach various parts together.  The recommended tube from McMaster is 1/4" diameter 316L.  Depending on the tube in question, either one or both ends must be threaded 8-32 x 1/4".  The first one I tried to tap normally was a problem.  The material is hard, and my HSS taps had heavy going.  Derek suggested that cobalt steel taps would cut it easily, but rather than that I decided to thread mill them.  I have a single point thread mill that up to now was used only to make studs, so this would be the first internal thread.  It took me a lot of trial and error to find a good set of code, and each thread took 5 minutes of machine time.  So rather inefficient to thread 10 holes, but at least I have the program saved for future use.  Here's the setup.

(http://www.pbase.com/kvom/image/166657953/large.jpg)

I got a shipment of aluminum today, so I should be ready to make more parts.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 02, 2017, 01:56:29 AM
Wow - this is going to be a great looking sculpture!

 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: 10KPete on December 02, 2017, 02:33:01 AM
I had no idea one could mill such small threads! Wow.
 :ThumbsUp: :ThumbsUp:
  :popcorn: :popcorn:

Pete
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 02, 2017, 12:43:59 PM
The place I bought that thread mill sells one for #0 threads.  :o
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 02, 2017, 02:23:38 PM
I don't get how an internal thread can be milled, any diagrams out there??
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on December 02, 2017, 02:53:30 PM
See if this helps...

https://www.google.com/url?sa=t&source=web&rct=j&url=https://m.youtube.com/watch%3Fv%3DrDnavOlGcdc&ved=0ahUKEwi2yM32yOvXAhUH04MKHUEwCXYQwqsBCDYwAA&usg=AOvVaw1Cyi7lePv4Wp8C5jdzPbSp

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 02, 2017, 03:36:35 PM
That video is a bit deceptive.  The tool shown has multiple teeth and as such can cut only threads with the same pitch.  It can cut multiple diameters, limited to the size of the hole for internal threads.  These tools are be fast as they need to go around the work once if the thread depth is less than the number of teeth.

In my example, the cutter has only a single cutting edge with three teeth, so it can do multiple pitches, obviously limited by the width of the teeth vs. the diameter of the shaft.  In this case, I can mill only a bit more than 1/4" of threads.  I also have to make a complete turn for each pitch depth.  In this case, 32 tpi x 1/4 means 8 times around.  I also make 3 passes, similar to single pointing.  In brass I could get away with 2, but I also make a spring pass to clear up any burrs and to compensate for any flex in the tool. 

The single tool cutters have a ramp angle in the tooth profile that limits the pitch range.  The tool in the picture can do down to 56 tpi.  The feed rate needs to be much smaller for internal vs. external threads.  One starts with the required SFM for the material to be cut to determine the RPM.  Then you use that plus the chip load (inches per tooth) times the number of teeth in the tool to determine a linear feed rate.  Finally you convert the linear feed rate to actual taking into account the diameter of the tool path.  In essence, you want the time to complete a single circuit of the work to be the same regardless of the diameter.

I have a larger thread mill that can cut 1/2" internal threads.  I used it on the Joy engine to make all the 1/4" studs. 

I also have a 27 TPI NPT thread mill I used to thread brass tube 1/16-27 and 1/8-27 for piping the loco.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 02, 2017, 05:52:44 PM
Thanks Bill/Kvom - makes sense to me now, clever use of CNC control. 

Back to watching the project!   :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 05, 2017, 09:56:00 PM
Some progress after getting a shipment of aluminum via eBay.  Alloy is Mic 6 (cast);  I like it since the finish on both sides is good, and as well drilling causes the swarf to be little chips rather than stringers.  I tried to get 5 parts from one piece of material, but one was too close to the edge and broke off.

(http://www.pbase.com/kvom/image/166678458/large.jpg)

I also got the other two hypocycloidal gears back from Shapeways, this time in the polished material.  While it's a bit smoother than the first one, I wouldn't call the surface polished.  Also, the center hole is a bit smaller than the first, probably about 2 thou, so the eccentrics will need to be turned to fit.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 08, 2017, 11:45:49 PM
Another batch of parts machined from a single piece of 1/2" cast aluminum.

(http://www.pbase.com/kvom/image/166689991/large.jpg)

The part on the lower left, labeled "wing frame support right", while it won't be used until fairly late in the assembly, proved instructional.  The plans call for a 7/16" (.437) countersunk hole for the needle bearing, whose diameter is .439".  I assume that would be a press fit in wood, but too tight for metal.  Given that there are 16 such bearing in colibri, I'll need to keep this dimension in mind for similar counterbores.  I intend to machine a sliding fit and secure with loctite.

The same part has a 5/64 hole (obscured by the bearing) that's used along with the bearing diameter to connect the part with its mate while they are glued together.  The plans specify a #2 wood screw though both parts ;  I will actually be screwing the parts together with a 2-56 screw, so this hole needed to be a #2 clearance and drilled with a #43 drill.  The mating part will need it's hole to be tapped.  That's a lesson to go back to the assembly drawings to see how each part is mated and modify the DXF and machining instructions where needed.

I located a piece of stock with dimensions large enough to make the main frame but not too large for my mill.  It's 5/16" thick while the plans call for 3/8".  Originally I didn't think the frame thickness was critical as the datum for most of the mechanism can easily be the face of the frame.  However, reviewing the assembly more closely I see that the body parts of colibri are centered over the frame, meaning that I'll need to offset the mechanism spacers by an additional 1/32" or do some shimming, and the bird's head needs to be the same thickness as the frame.

One other painful lesson this week is that even with peck drilling and .06" pecks, 1/16" drill bits don't care for a vertical feed of 22 ipm instead of the recommended 2.  Need to proofread the CAM entries or the g-code a bit more closely.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 10, 2017, 06:49:28 PM
More parts as a result of the past two days in the shop.

(http://www.pbase.com/kvom/image/166696619/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on December 10, 2017, 06:57:20 PM
All the parts are looking great Kirk. Are you getting close to doing any of the sub-assemblies yet?

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 10, 2017, 07:19:39 PM
Looking fantastic! It would make a great puzzle - hand someone the box of parts and see how long it takes to figure out what/how to build it!

 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 10, 2017, 07:55:10 PM
All the parts are looking great Kirk. Are you getting close to doing any of the sub-assemblies yet?

Bill

Many of the sub-assemblies involve gluing or otherwise hard to undo assembly.  My plan is to dry fit everything first.  to re-check vertical alignment.  There are 15 different spacers, mostly round disks with center holes needed for this purpose.  I will turn these from either aluminum or brass as I go.  I have stock being shipped that will be used for the 4 main "frames" and the long tail cam follower.  Once the frames can be put together I'll have a basis for attaching the sub-assemblies.

I'm still debating on what to use for the larger center gear.  Brass in that size is too expensive.  I may end up with Lexan or similar.

In the mean time I still have some smaller parts to machine out of the aluminum sheet I already have, not to mention more acrylic parts.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 11, 2017, 11:31:50 PM
The "pivot blocks" are part of the wing articulation.  As the outer profile fits (just) within a 1.125" circle, a 5C collet can be used for workholding.

(http://www.pbase.com/kvom/image/166703592/large.jpg)

Afterwards it is parted in the lathe and finished on the manual mill.

(http://www.pbase.com/kvom/image/166703596/large.jpg)

I discovered that one of the cam wheels done so far has a misplaced hole for one of the guide pins.  I suspect that it happened when I was moving the part around in CAM to fit the stock and didn't select that hole.

(http://www.pbase.com/kvom/image/166703593/large.jpg)

The pin holes are supposed to be centered in the "spokes", so this stood out on close look.   But since all 4 cams have the same pattern and center hole, I was able to attach a good cam with pins and use it as a drill template.   :)

(http://www.pbase.com/kvom/image/166703594/large.jpg)

The hole in error will be covered up by a spacer.

(http://www.pbase.com/kvom/image/166703595/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 12, 2017, 09:32:22 PM
Today I tackled the 'A' spacers for the hummer body cam link.  These form the central part of a sandwich that includes and cam link as well as the two acrylic body parts.  On the wooden calibri these two spacer would be glued together than the rest of the sandwich assembled with 2 #2 wood screws on each side.  On my version, the center spacer is tapped 2-56 on both sides and the other has clearance holes.

These parts are small and their profiles fit together within a 1.125" circle, so again I use the 5C collet and aluminum rod.  The holes are only spot drilled as I lack sufficient Z height on the mill for any longer drills.

(http://www.pbase.com/kvom/image/166705754/large.jpg)

With the collet in a block, the holes are drilled on the bridgeport.  The center 1/16" hole will contain steel wire to align the spacers with the cam link, and the wire will be loctited to secure the two spacers together tightly with the link.

(http://www.pbase.com/kvom/image/166705755/large.jpg)

Parted off on the lathe, then milled both to .5" thickness, and did the tapping.  My 2-56 taps aren't long enough to through tap .5" holes, so they were tapped halfway from each side.

(http://www.pbase.com/kvom/image/166705756/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Kim on December 13, 2017, 07:26:53 AM
... My 2-56 taps aren't long enough to through tap .5" holes, so they were tapped halfway from each side.

That is fascinating to me.  If you tap from both sides, how do you make sure the threads line up?  Did you do something special to get them to align?  Or do you not need the bolts to go all the way though?

I'm really enjoying your Colibri build! This is also on my wish list.
Kim
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 13, 2017, 11:19:36 AM
Separate screws on each side.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Kim on December 13, 2017, 06:01:03 PM
Ah, OK, makes sense.
Thanks,
Kim
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 13, 2017, 11:12:10 PM
Today's project was to machine two of the large three main gears that drive the hypocycloid and cams.  Material is .25" thick, 7" wide Mic 6 cast aluminum.  After drilling the 1/8" center holes, a 3/8" 2-flute end mill pocketed out the spokes and did a roughing pass to form the teeth.  The DOC was .20" making a trochoidal slot .50" wide.  Doing this, while slow, enables room to clear chips with air blast much easier.

(http://www.pbase.com/kvom/image/166710516/large.jpg)

Next, a 1/4" 2-flute endmill does the finishing pass and cuts the bottom of teeth where the 3/8" can't reach.  This material comes with a tough plastic film on both sides.  By leaving the film on the bottom, the endmill pushes down the film but doesn't cut through.  This helps retain the gear from moving, even if there are also 4 tabs on each gear.

(http://www.pbase.com/kvom/image/166710518/large.jpg)

After removing the film, you can see that the profile was cut all the way through except for the tabs.  These are snipped in two and the stubs removed with the disk sander.

(http://www.pbase.com/kvom/image/166710519/large.jpg)

The finished gears with the smaller brass pinion.  Only other finishing needed was deburring the spokes.

(http://www.pbase.com/kvom/image/166710520/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Myrickman on December 14, 2017, 12:24:38 AM
Kvom, that's is certainly a neat build. I'm just starting down the cnc rabbit hole with a used Isel gantry and adding new electronics so seeing your build is inspiring to say the least.  I'll be following with great interest. Paul
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Tennessee Whiskey on December 14, 2017, 06:59:02 PM
Finally had a minute to catch up. Man, this is going to be awesome. I couldn’t help but laugh and wonder: Wonder if G. Britnell is going to try this manually?  :lolb:. Nice work Kirk

Cletus
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 14, 2017, 09:02:49 PM
Manually in wood with a good jigsaw and patience it's achievable.  In metal w/o CNC it's hard to imagine.  Wood with a big CNC router you could cut out all the pieces in a day.

My project for today was one of the frame supports that forms the right side of the bird.  It's only difference from the left is a hole for mounting the bearing that follows the body cam and causes the entire frame assembly to rotate up and down.

The stock is 7x17.5x.25".  Plans call for 3/8" thick, but this is what I could find.  I used a feature of the CAM program to rotate the entire drawing so as to minimize the Y extrema and thus minimize the amount the outer profile cut would eat into the aluminum vise jaw.  This left the X extrema at 16.2".  The vise jaws I'm using are 12" long on my 6" vise.  I didn't want to do much if any machining on material that overhangs the jaws, so it would be necessary to shift the work several times before completion.  Another complication is that my mill's X travel is 20", meaning that for reaching the left edge of the stock is could protrude at most 3.5" from the left edge of the jaws.

I settled on a machining origin as the center of the topmost hole which accepts a rod to attach the flower stem on the complete model.  This hole would be 1" from the top and left edges of the stock.  I used an edge finder on the fixed jaw to establish Y0, and that never changes throughout.  Each time I needed to slide the stock one way or another I merely needed to use the edge finder on the left edge at Y0 to reestablish X0.  With that accomplished, the first stage was to drill all the 1/4" mounting holes as well as the 3 leftmost pockets.

(http://www.pbase.com/kvom/image/166715081/large.jpg)

After a shift left, we have the righttmost pocket, the hole for the pivot bearing, and half of the trochoidal rouging pass for the outer profile.

(http://www.pbase.com/kvom/image/166715084/large.jpg)

After some more operations the CNC was finished, so I needed mainly to sand off the tabs and deburr.

(http://www.pbase.com/kvom/image/166715086/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 14, 2017, 10:26:44 PM
quite impressive!

 :popcorn: :popcorn: :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on December 14, 2017, 10:29:13 PM
It sure is!! You are getting a nice collection of components now Kirk.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 16, 2017, 11:53:14 PM
The manual 1-shot oiler for my mill broke halfway through the matching B frame, so no more Colibri parts until I get that sorted.   :'(
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 17, 2017, 08:31:01 PM
With the CNC mill out of commission for a few days, I can work on some round parts.  These spacers for the 3 large gears are brass disks 1.25" in diameter with a 1/8" hole for the axle.  An 8-32 grub screw locks it to the axle.

(http://www.pbase.com/kvom/image/166726338/large.jpg)

In the wood model a spacer would be glued to the gear.  The 1/8" steel axle would be secured by grub screws on both the hypocycloid eccentric and the spacer.  An instruction tip indicates the potential need to adjust the gear timing by disengaging it from its mates and rotating it (and the cam) by one tooth.  With the wood gear apparently it's flexible enough to bend it out of engagement.  I fear this is not the case with a metal gear.  I'm still considering the best way to accommodate this need.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 19, 2017, 11:21:34 PM
The next pieces are similar to the spacers, but are the eccentrics that drive the hypocycloid gears.  As such they need to have a smooth sliding fit to the center of the hypocycloid gears that I had printed at Shapeways.  It turns out that there is a .005" spread in those diameters, so I turned down and parted off each after specifically fitting to a given piece.

The diameters are nominally 1.125", so I could hold them in a collet in order to drill the 1/8" hole for the axis, offset .40" from the center.

(http://www.pbase.com/kvom/image/166736800/large.jpg)

(http://www.pbase.com/kvom/image/166736802/large.jpg)

Each is secured to the shaft y a 8-32 grub screw, so it's necessary to drill from the opposite side.  I couldn't figure out the reason of the 1/16" hole in the center so I emailed Derek Hugger.  Turns out it's so the disk can pivot on a metal pin while being sanded on a belt sander.  That's how the wooden version can be turned to fit when the builder doesn't own a lathe.  But I was able to put it to use here.

(http://www.pbase.com/kvom/image/166736804/large.jpg)

The centerline for drilling is parallel to the top of the jaws of the small vise, so when mounted on the manual mill an edge finder suffices to locate the hole location.

(http://www.pbase.com/kvom/image/166736806/large.jpg)

Since the depth of the hole is longer than the teeth on the tap, I drilled the first 1/2" of the hole with an 8-32 clearance drill and the rest with an 8-32 tap drill, allowing the tap to penetrate deeper than the circumference of the disk.

After deburring the edge of the tapped hole, the part is finished.

(http://www.pbase.com/kvom/image/166736803/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on December 20, 2017, 12:14:01 AM
More good progress Kirk. I am watching closely even though I plan to use the brown stuff  :)

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 20, 2017, 11:04:32 PM
Minor progress today making 4 frame spacers (actually 3 as 2 are combined) in aluminum rod with a center hole.  Not worth a pic.

Rather than mount the vacuum chuck in the vise, I decided to raise the secondary table a couple of inches and mount it there (I'll need to remove the Kurt vise).  To raise it I ordered a pair of 2-4-6 blocks from MSC.

That left the afternoon open so I did a swarf cleanup of the CNC mill and  Bridgeport and floor for the first time in a while.  There was a lot of it.   :embarassed:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 21, 2017, 11:54:37 PM
The oiler replacement came this afternoon, so I can get back to making non-round parts soon.  In the meantime I did a mockup of the cam action using the gear spacer to drive the motion.

pSuW3rfWbao
As the hypocycloid gear rotates, the 4 pins in the cam travel around its round holes.

There's a bit more friction than I expected;  however, the frame material is a lot smoother than the mockup.  I might need a bit of PTE sheet next to the frame.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 22, 2017, 08:22:29 PM
With the mill back in operation, I finished the B side frame.  Then it was time to drill and tap mounting holes for the base.


(http://www.pbase.com/kvom/image/166750724/large.jpg)

Just enough room to clear the Bridgeport table.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Vixen on December 22, 2017, 08:43:16 PM
Hi Kirk
What is that red anodised frame we see in some of your photos? It sure looks interesting.

Mike
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 22, 2017, 09:12:46 PM
It's an adjustable vise stop.

http://www.edgetechnologyproducts.com/pro-vise-stop-single-side/
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: fumopuc on December 23, 2017, 04:59:30 AM
Also available in the UK.
https://www.machine-dro.co.uk/edge-technology-single-pro-stop-4-inch-vice-stop.html
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 27, 2017, 08:49:17 PM
I got the vacuum chuck set up on the  mill.

(http://www.pbase.com/kvom/image/166767126/large.jpg)

I needed to put the sub table on setup blocks to raise it 2" so that the spindle can get within an inch or so.  The air connections are from my compressor (nominal 125 psi) through the adjustable valve (to 85 psi) to the vacuum generator and then to the chuck.  The silver knob on top of the generator locks and releases the stock.  The picture shows a 12x12" sheet of .236" acrylic mounted on the chuck.  With the vacuum applied I couldn't budge the sheet with my hands.  The gasket forms a square about 10x9" so a theoretical holding force of over 1200 pounds.

I trammed the front edge of the chuck plate parallel to the X axis motion, and the top of the chuck is flat within .001" side to side.  Now I just need to figure how close without breaking through or cracking the acrylic I can go.  This sheet should yield the flower petals and the body of the bird.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 27, 2017, 10:01:54 PM
Slick setup with that chuck! Well, apparently more sticky than slick. Anyway - are there independant slots/chambers spaced around the surface of it, or is it one set of slots with holes? Not sure how it is set up, does it work for smaller parts as well? Maybe a close-up shot of the table would help?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 28, 2017, 02:26:04 AM
The slots are precisely cut in a grid fashion.  The area of the vacuum is sealed off by tubular rubber gasket material inserted in the slots, and there are 9 threaded holes over the table to introduce the vacuum inside the "roped off" area(s).  You only need one hole open in an area, and all the rest are closed off with screws.

The holding area can be fairly small, but the holding force is 14psi over the roped off area, so the best usage is wide and thin material, just the type that's hard to hold in a vise.

I'll post a photo of the top of the plate tomorrow.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on December 28, 2017, 03:03:13 AM
The slots are precisely cut in a grid fashion.  The area of the vacuum is sealed off by tubular rubber gasket material inserted in the slots, and there are 9 threaded holes over the table to introduce the vacuum inside the "roped off" area(s).  You only need one hole open in an area, and all the rest are closed off with screws.

The holding area can be fairly small, but the holding force is 14psi over the roped off area, so the best usage is wide and thin material, just the type that's hard to hold in a vise.

I'll post a photo of the top of the plate tomorrow.
Clever, thanks!
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 28, 2017, 10:58:08 PM
Here's a pic showing the gasket material in the slots:

(http://www.pbase.com/kvom/image/166770003/large.jpg)

And here's the first cuts using the chuck:

(http://www.pbase.com/kvom/image/166770004/large.jpg)

Since the acrylic sheet and paper covering varies in thickness, I set Z0 to the surface of the chuck.  Then it was a question of setting the target depth as the thickness of material to leave.  On the first part I set it at .015", and it had no indication of wanting to move.  The other 3 were at .01".  I probably could have done a little deeper, but probably not necessary.  I measured the back of the chuck plate as .003" higher than the front, although side to side is flat to less than .001".

Cut with a 1/8" 2-flute carbide endmill .05" deep at 10 ipm.

Five other parts remain to be cut from the sheet before trying to break them out.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 29, 2017, 08:34:42 PM
Got all the parts cut from the sheet:

(http://www.pbase.com/kvom/image/166773350/large.jpg)

Parts made here are 5 halves of the petals, 2 sides of the body, 2 sides of the head, and a possible candidate for the central gear.  I'll have to see if the color is a poor visual choice within the mechanism.

It turns out that the .01" flashing remainder made it very easy to cut the parts out and then deburr with a small deburring knife.  The first piece I did with a .015" remainder was quite a bit harder.

I used the same amount for drilling in the hope that I could finish the hole by merely pushing the drill bit through by hand, but that didn't work.  So I'll need to drill them manually.  I think that for other parts I'll got deeper, probably to .005" above the chuck surface.  The few 1/8" holes that were drilled with an endmill were easy to push through, so obviously the conical bottom of the other holes was the problem.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on December 29, 2017, 09:29:57 PM
Those look fantastic Kirk. Sounds like the vacuum chuck worked out very well for this too. Once the vacuum is applied, how much clearance is there between the underside of the material being cut and the actual surface of the chuck?  Just wondering if the vacuum compresses the gasket material until the clearance is virtually nil?

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 29, 2017, 09:40:50 PM
I suspect clearance is zero.  I can't see any at the edge of the stock.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 30, 2017, 11:04:19 PM
Today I did the same type of machining on the green acrylic for the flower's stem.  Since that's the only other part that's green, I decided to cut out green read petals in case I like that look better than the red ones.

(http://www.pbase.com/kvom/image/166778723/large.jpg)

These petals need to have two 2-56 threaded holes in the ends for assembling the flower.  Here is the setup for doing so.  By using a vise stop and spindle stop, I was able to do the drilling in assembly line fashion.  I was only able to tap one of them before I had to leave for a family obligation.

(http://www.pbase.com/kvom/image/166778724/large.jpg)

The two holes the stem are overlarge due to a CAM error on my part (3/8 vs. 1/4).  I'll make a couple of brass bushings to compensate.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Hugh Currin on December 31, 2017, 03:49:26 AM
Kirk:

Good stuff, like the project. Thanks.

I've been thinking how to use the vacuum chuck and machine through. Suddenly realized today that you can't. Once the cutter plunges through the vacuum is lost. A non-starter but took me awhile to come to my senses.

Thanks for the writeup.

Hugh
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 31, 2017, 01:10:54 PM
If the work overhangs the chuck you can plunge through.  In addition to losing vacuum otherwise, you also end up with a hole in the chuck.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on December 31, 2017, 03:50:52 PM
Kirk,
Its great to see this progress. I like the idea of the vacuum chuck, but I could picture myself going to deep, and watch the stuff fly. :ROFL:
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on December 31, 2017, 06:22:06 PM
Art, it is a bit nerve wracking.  I set the tool Z0 to the surface of the plate and the target depth to .01".  Should be idiot proof, but they're always improving us idiots.

It's certainly possible to use the gaskets to form two separate vacuum areas as "insurance".
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 03, 2018, 01:16:19 AM
I cut the first two parts from some .375" aluminum stock today using the vacuum chuck.  Had some strange results but no disasters.

The machining involved two profiles and one pocket.  As the pocket is long and narrow (.439" wide) I did it as a ramped profile with a .25" endmill.  The target depth was .01" above the vacuum table.  No issues.  For the other profiles, I first programmed thenm as a trochoidal slot .375" wide using the same .25" endmill; this at .05" above the table with a .01" roughing clearance.  Doing this allows the chips to be cleared more easily than in a straight slot  Then to finish a finish profile at .01" above the table (.04" DOC).  This pass caused the material at the bottom to break off and in addition caused the bottom film to break, thus losing vacuum.  However, the vacuum table showed no machining marks, so it wasn't touched.  Luckily no damage to the parts resulted.

The only thing I can figure is that the endmill caused a vertical force on the bottom of the slot that was strong enough to break it off in places.  For future work I'll increase the table clearance to .015".
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: 10KPete on January 03, 2018, 03:40:49 AM
Plate warp??

Pete
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 06, 2018, 02:10:09 AM
Here are the two parts mentioned in my previous post.

(http://www.pbase.com/kvom/image/166807712/large.jpg)

The long part is called the Cam Follower Tail, and the smaller is the Hummer Body Cam link.  The latter is shown assembled with the two spacers made in a previous post.  The screws are temporary as the right side of the body is attached to the opposite side from the spacers and the left side of the .body is attached to the spacers.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 08, 2018, 01:33:09 AM
Having received the 1/8" acrylic sheet I ordered before New Years, I was able to cut out the 5 "forward" petals as well as the tail feather I was lacking.  The fit with the "rear" petals is quite firm, so perhaps they won't need glue.  Still not sure if the all red or the green-red combo looks best.

(http://www.pbase.com/kvom/image/166817952/large.jpg)

I think cut out the support frame from 1/4" aluminum.  This time I left a 0.015 flashing, but this proved really tough to remove with the deburring knife.  Plus a CAM error left an evident gouge that I stopped before it got too deep, but I'll need to run a face mill over the part if I can figure out how to hold it.

I'm hoping to get the main frame machined before needing to pack up for Cabin Fever.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 08, 2018, 02:46:27 AM
The combination of the colored plastic sheet with the metal parts is going to look great.

 :popcorn: :popcorn: :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 09, 2018, 12:17:14 AM
Today was spent machining the frame, the most complicated part of the sculpture.  Started at 11:00am and finished the CNC about 5:00pm.  The most concerning part was drilling the 30 1/16" holes for the hypocycloid pins, since a broken drill bit in any one probably ruins the part.  I single stepped these spraying the bit with WD40 and cleaning it after each hole with a brush.  Here's the work at the end of the machining phase.

(http://www.pbase.com/kvom/image/166823862/large.jpg)

I had taken the cuts down to .01" above the table, so the flashing was quite a bit easier to remove.  Still there were a lot of edges to deburr.

(http://www.pbase.com/kvom/image/166823863/large.jpg)

I also had to drill the holes through the last .01" with a hand drill.  Not the 1/16" holes as the pins don't have to go through.

I still need to tape two holes 2-56 and loctite bushings in the gear axis holes, then place the pins.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 09, 2018, 12:38:17 AM
That is a very intricate part Kirk. I can see how the beburring could get tedious.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 09, 2018, 12:41:08 AM
That is spectacular! How many more parts to make?

 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Dave Otto on January 09, 2018, 01:00:09 AM
Nice looking part Kirk!

Dave
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 09, 2018, 01:00:47 AM
Other than the wings, that's the last that needs the vacuum table.  But I'll probably use it for some of the larger parts left (e.g., 2 more cams).  There's about 20 parts left to machine, but about 50 various rods and bushings to cut to size.

No more before CF as I need to see if the other engines will run before I pack up on Wednesday.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 17, 2018, 11:43:11 PM
Back from CF to find freezing temps and snow last night.  Good reason to stay in the shop most of the afternoon.  The first job was to cut the wings from the translucent acrylic sheet I bought at the show.  There was even enough room on the sheet to make another set of petals in case I like the color better.

(http://www.pbase.com/kvom/image/166872590/large.jpg)

As long as I was on the wings, I decided to do the drilling and tapping on the shoulder parts I made earlier.  As I needed to drill a very deep 1/8" home into parts with no flat edges, I cut out the actual size drawing and help it against the part in the vise for alignment.

(http://www.pbase.com/kvom/image/166872591/large.jpg)

More drilling and tapping for grub and mounting screws:

(http://www.pbase.com/kvom/image/166872593/large.jpg)

And here's how the shoulder and wing go together.

(http://www.pbase.com/kvom/image/166872594/large.jpg)

There will be a thin shoulder on the opposite side of the wing to clamp it.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 17, 2018, 11:53:31 PM
Glad to see you back on it after CF Kirk. Should be an amazing end result!!

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: cheepo45 on January 18, 2018, 05:26:13 PM
Very nice!
Can't wait to see it in action.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 18, 2018, 10:47:23 PM
Today I wanted to make the 7 remaining parts that are 1/8" thick.  However, apparently Mic6 doesn't come in 1/8" sheets, so my idea was to use 1/4" plate, machine down 1/8", and then face off the bottom.  Unfortunately the best piece of material I found had room for only 6 of the parts, so I included the ones that are needed soonest in the assembly.  Here's the result:

(http://www.pbase.com/kvom/image/166875917/large.jpg)

The 4 on the left are spacers for the cam wheels, and the two on the right are the thin shoulder pieces.

Unfortunately the face off plan didn't work as clamping the sheet in the mill vise bowed it, and the face mill screeched when trying to cut it.  So I decided to cut all of them out individually.  The shoulder pieces could be clamped in the vise firmly enough for the facing op, and the round parts were faced on the lathe.  For the odd shaped cross I'll probably need to make soft jaws for the vise.

(http://www.pbase.com/kvom/image/166875918/large.jpg)

My day's production:

(http://www.pbase.com/kvom/image/166875919/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Dave Otto on January 19, 2018, 12:41:24 AM
Hi Kirk

Why not thin them up while everything was still in one piece and on the vacuum chuck?
You could do a pocket routine on each part so you are not cutting the entire piece of stock?

Dave
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 19, 2018, 12:50:18 AM
Once they were milled the chuck couldn't maintain vacuum.  A better idea in retrospect was to facemill the stock to thickness as the first op.   :noidea:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Dave Otto on January 19, 2018, 01:01:16 AM
Yes that is kind of what I was thinking, only just pocket each part down to 1/8" thickness then do the profile. The other option is, they do make 6061 T6 rolled aluminum plate in 1/8" thickness.
You are making good progress on this one.

Dave
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on January 19, 2018, 01:53:33 AM
Kirk,
Dito on what Dave said. Seems you could have done the 1/8 thickness with a face mill then did the profile. Hind site being 20/20 and all. :ROFL:
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 19, 2018, 02:53:10 AM
6061 would have been OK for the spacers since they're no very visible .
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 20, 2018, 12:50:06 AM
It seemed to me that the remaining spacer could be milled to thickness on the Bridgeport if clamped fairly lightly and light cuts used.

So it proved to be:

(http://www.pbase.com/kvom/image/166880241/large.jpg)

(http://www.pbase.com/kvom/image/166880244/large.jpg)

Then I moved on to making the last remaining pieces from 1/2" plate.  One of the problems I foresaw was drilling small, deep holes.  I used peck drilling, and also kept the bristles of a brush around the drill bits while in operation.  This had the effect of clearing the flutes on each retract.  After several hours I had this:

(http://www.pbase.com/kvom/image/166880245/large.jpg)

Another hour of deburring plus drilling out the remaining .01" in all of the holes:

(http://www.pbase.com/kvom/image/166880246/large.jpg)

The list of parts needed to be cut from plate is pretty small at this point.  There's a group that can be done together from some 3/8", plus some more spacers from round stock.  A number of parts need lateral (xy plane) holes drilled and/or tapped, so I'll start to polish these off pretty soon as well. I don't have material big enough for the base as drawn, but I may make a temporary one for use in the assembly.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 20, 2018, 11:58:36 PM
I took a parts inventory today and discovered two 1/2" parts are missing plus I screwed one up yesterday.  Seems in adjusting a parts location on the stock I moves the profile but no the holes.  You can see the bottom part on the photo has the holes off center.

I also found four 3/8" parts left to do, and I started to machine them on the vacuum chuck.  I machined a pocket just slightly too deep, and the flashing cracked and slit the film underneath.  So I lost vacuum.   Luckily the stock didn't move enough to cause a problem before I shut it down.  So I reduced the vacuum area to exclude the leaky pocket, and continued on.  But now the machining force apparently was enough to move the stock on the table.  So I'm going to finish this when I remount the vise tomorrow.

There are also two 1/4" parts that will also be done on the vise.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 22, 2018, 10:14:56 PM
Today I finished what should be the last 3/8" parts to be machined on the mill.  As stated on the previous post, I had to move the work to the vise, which meant swapping the vacuum check for the vise, tramming, etc.  Anyway, worked through it all and ended up with this assortment.

(http://www.pbase.com/kvom/image/166894839/large.jpg)

The long pointed part is the bill, a section of which I'll either paint or dye black.

Now with the vise installed I could make the center section of the flower from some 1.5" hex  brass.  I turned one end down  on the lathe so that I could find the center before milling.

(http://www.pbase.com/kvom/image/166894840/large.jpg)

Then back to the lathe to part it off.  Here's a trial fit with one of the petals and the stem.

(http://www.pbase.com/kvom/image/166894841/large.jpg)

I'll have to shorten the screws of course.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 22, 2018, 10:30:19 PM
You mention dyeing a part - with what?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 22, 2018, 10:45:16 PM
I have some chemical blackener that works on aluminum.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 24, 2018, 11:52:03 PM
Spent the day doing subassemblies.  Most of the work for these involved turning spacers and parting tube at the lathe.  But the first job was to fix up a temporary base from a piece of 10x10" aluminum and attach the support frames to it.  I used the dimensions from the plans for the holes.  But since the frames are made from 1/4" plate vs. 3/8" wood, the space between the frames is 1/8" wider than per the design.  That shouldn't make a difference as long as the main frame is shifted right 1/16.  And even that isn't a big deal.  The position of the main frame within the support frames is decided by a spacer on the drive shaft that passes through the lower pinion gear.

(http://www.pbase.com/kvom/image/166904697/large.jpg)

You can just see a bearing mounted inside the right support frame.  The bottom cam rides on this and controls the up and down motion of the entire mechanism.

The 4 assemblies show below form part of the mechanism that drives the flexing of the wings.  Each pair is connected by a strong magnet that allows them to rotate relative to the magnet axis.  The magnets were chosen in the design because of very little space for any other type of rotational fastener that would be easy to fabricate.

(http://www.pbase.com/kvom/image/166904695/large.jpg)

The 3 assemblies shown below are the "followers" for the other 3 cams.  Two have needle bearings that ride on the cam, and the smaller one on the top rides the the small nub.  I'm wondering if this could cause a galling problem on the aluminum cam.  Similarly, the round spacers will contact the faces of other spacers on the frame.  These can be separated by brass shims if there is a problem.

(http://www.pbase.com/kvom/image/166904696/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 25, 2018, 02:14:41 AM
Ooohh! Now we are getting close to seeing how all those shapes come together! 




 :popcorn: :popcorn: :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 25, 2018, 11:44:01 AM
This is all looking really great Kirk!! Now the fun part of seeing it all come together and working!

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 25, 2018, 10:23:05 PM
Today I attacked 6 more sub assemblies.  The first is the "hummer body right" which combines the right side of the body (red acrylic) with the cam link that drives it.  In Colibri, each of the 3 cams (tail, body, and head) have a "follower" that pivots as the cam turns.  The followers have a slot in which bearings attached to a cam link travels.  The combined motions of the follower and link result in the motions of the three main parts.

(http://www.pbase.com/kvom/image/166911383/large.jpg)

The left side of the  body will be added to the other side at a later stage of the assembly.

Here are the two spinner assemblies.  They will eventually be connected by a shaft and activate the wings.  Since the small gear turns 8 times for each full rotation of the cames, the wings will "beat" 8 times.

(http://www.pbase.com/kvom/image/166911380/large.jpg)

The most time consuming job of the day was mating the cams with their spacers and pins.  Having drilled the holes for the pins with a 1/16" drill, I found them too tight to insert through the cams and spacers.  By enlarging the holes with an .063" drill #52 I was able to get a moderate press fit.

(http://www.pbase.com/kvom/image/166911381/large.jpg)

The pins ride in the circular openings in the hypocycloid gears while the 1/8" shafts from the eccentrics ride in the centers of the cams.

The number of unattached parts is getting smaller day by day. 
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 25, 2018, 10:26:28 PM
 :popcorn: :popcorn: :popcorn: :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: zeeprogrammer on January 25, 2018, 11:26:17 PM
What Chris said... :popcorn: :popcorn: :popcorn: :popcorn:
I've not commented...but I've been following along. It's a fascinating project.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: 10KPete on January 25, 2018, 11:49:44 PM
This is sooo neat to watch it come together!!

 :popcorn: :popcorn:

 :cheers:

Pete
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Vixen on January 25, 2018, 11:59:59 PM
 :popcorn: :popcorn: :popcorn: :popcorn: :popcorn:

Me and my Petite Colibri are waiting and watching and not saying a word

Mike
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 26, 2018, 04:54:27 PM
Thanks for checking in, friends.   :-*

This morning I wanted to do a tryout of one of the cams with the frame.  After cutting off a 2" axle of 1/8" drill rod, I made a sandwich on it consisting of the brass gear spacer, frame, eccentric, hypocycloid, cam assembly, and a retaining collar.  I could not turn the sandwich.  Since it turns relatively easily without the cam assembly, it was clear that the fit between the hypocycloid and the pins on the cam assembly were too tight.

Following the instructions for a similar situation with wood, I wrapped some 180-grit sandpaper tape around a finger and lightly sanded the holes in the hypocycloid.  After reassembly, I was able to turn the shaft, and it seemed to loosen up even more after a few rotation.  I had a similar experience with the eccentrics in the hypocycloid loosening up with use.  As long as the pins don't wear the plastic too much we should be good.

Here's a short video of the motion.

JnG-PFV59zU
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 26, 2018, 05:08:17 PM
Very nice Kirk and whatever you did seems to have freed it up nicely!!  Still watching with interest.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on January 26, 2018, 07:23:44 PM
Kirk,
That looks good. Yes I'm still following along.
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 26, 2018, 11:52:06 PM
Each of the gear sandwiches need to be tested individually, so that can wait.  I decided to start on the remaining CNC parts.  Here's the result at the end of the day.

(http://www.pbase.com/kvom/image/166915628/large.jpg)

The two on the right are the main mounts between the frame and the rest of the "bird" parts.  Since they pivot against the frame brass was required.  The center part (one of a pair, with the other one a job for tomorrow) is the connector between the wings, wing frame, and the pivoting linkage.  Further drilling and tapping are required to finish them. 

The part on the right is the flange to which the counterweight will be attached at the end of the build.  It's from brass mainly because it could be machined at the same time as the mounts.  Here's the flange attached to its arm.

(http://www.pbase.com/kvom/image/166915629/large.jpg)

The shoulder pivot was machined from some 1-7/8" hex bar.  After the profile is machined, I parted part way on the lathe, and then used the bandsaw to cut the rest of the way.  Then a facemill on the Bridgeport to bring to size.

(http://www.pbase.com/kvom/image/166915627/large.jpg)

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 27, 2018, 11:27:48 PM
Today was "work on wings" day.  The first job was to mill the the other shoulder, and then to drill the three needed holes in each.  Since there are no right angles on the profile, the machinists vise, surface plate, and square were needed for each.  Vise stop made the drilling repeatable.  The quarter inch hole accommodates a steel tube that will ride in needle bearings on the wing frame to provide rotation around the "Y-axis", as seen from the side.  The eighth inch hole connects to the wing itself and yields rotation on the X-axis.  Then the frame itself rotates on the Z axis.

(http://www.pbase.com/kvom/image/166917727/large.jpg)

The next parts are a pair of aluminum tubes that connects the wing pivots to the heim joint.  We need a 3/32" hole that will contain a brass bushing.  The other end of the tube is tapped 8-32.  Here again a vise stop makes drilling the second part fast.

(http://www.pbase.com/kvom/image/166917728/large.jpg)

(http://www.pbase.com/kvom/image/166917729/large.jpg)

The two i/8" rods that connect the wings get flats for the grub screws.  I was able to use the same vise setup as for the tubes to facilitate this.  3/16" endmill .005" deep.  The two flats on the left are for the wing, and the one on the right secures the pivot.

(http://www.pbase.com/kvom/image/166917730/large.jpg)

(http://www.pbase.com/kvom/image/166917732/large.jpg)

(http://www.pbase.com/kvom/image/166917734/large.jpg)

(http://www.pbase.com/kvom/image/166917735/large.jpg)

I neglected to take a picture after the pivot tube was added, but it goes into the slot of the pivot and is secured by a 1/16" pin through the bushing in the tube.

The end profiles of the wing's shoulder plates and the wing itself didn't match perfectly, so a bit of fettling is needed to allow the shoulder to pivot freely against the wing.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Perry on January 28, 2018, 10:12:51 AM
Im watching your progress, all parts looks great!  :ThumbsUp: Will for sure come back to this once I start to build mime.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 29, 2018, 02:02:43 AM
Hi Perry,

If you decide to build in metal like this the major thing to be aware of is that all the parts attached with #2 screws from the plans need to have tapped holes in the part being attached to.  I've also found having oversize reamers for .126 and .251 and a .063 drill are a necessity.  I've also attempted to avoid any places where one aluminum part moves against another.

Today in the shop I started the day with assembling the head unit.  I  needed to through drill the holes in the acrylic as these were cut on the vacuum table.  I just used a hand power drill for this.

(http://www.pbase.com/kvom/image/166927690/large.jpg)

The other work needed here was to turn the 1/4" aluminum spacer and the 1/8" brass spacer and glue it all up with Loctite.

I had made a mistake on the acrylic by making them both from the same DXF, but it turns out the screw holes on the two sides are offset to allow use of the 4 holes in the hummer bill.  However, I was able to use the same two holes for both as my 2-56 screws went in less than halfway through.

The rest of the afternoon involved attaching the brass gear spacers to their gears.  In the wood version these spacers are glued, but I wanted a removable attachment.  This, I needed to drill the gears for two 2-56 screws and tap the spacers to match.  This involved some ugly setups, but eventually I got there.

(http://www.pbase.com/kvom/image/166927691/large.jpg)

(http://www.pbase.com/kvom/image/166927692/large.jpg)

I did a trial attachment to the frame with the acrylic gear and one of the aluminum ones, and got a very satisfactory mesh of th gears, and they turn quite freely.  Even pressing the gear spacer against the aluminum frame didn't cause appreciable friction.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on January 29, 2018, 02:04:31 AM
Coming along great. My shop elves keep asking when they can take a flight on the hummingbird!

 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 29, 2018, 09:45:05 PM
Update for the shop elves.  Spent the day working on getting gear train and cams moving on the frame.  Much tedium in machining shafts and tubes plus fettling.  I needed to sand one of the hypocycloids, but now all three are moving when the gears are turned.  One is stiffer then the others, but I can still turn the entire mechanism with a finger on a gear tooth.  I suspect it will loosen up with more running in.

Next time I need to machine the spacers for the cam followers so I can see how they line up with the cams.

(http://www.pbase.com/kvom/image/166933822/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 29, 2018, 11:09:25 PM
Most impressive Kirk!! Shouldn't be long now. Happy things are going together well on it.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 30, 2018, 10:46:50 PM
Colibri had an erection!   :cartwheel:

(http://www.pbase.com/kvom/image/166938944/large.jpg)

(http://www.pbase.com/kvom/image/166938945/large.jpg)

With the mechanism mounted on the base, I was able to measure and make numerous spacers.  I needed three for the cam followers and four for the input shaft.  I still have a couple more to do there plus mill flats on the shaft for the crank and the small brass gear.

Weight of colibri as she sits is ~ 12 pounds.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Tennessee Whiskey on January 30, 2018, 11:02:07 PM
ZfYFx6MOTYU :lolb: :lolb:

Great work BTW

Cletus
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: 10KPete on January 31, 2018, 04:34:23 AM
Thanks, Cletus. That brings back the memories...

Pete
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on January 31, 2018, 12:33:20 PM
That is looking wonderful Kirk!!  At 12 lbs. plus it shouldn't fly away on you either :)

Cletus, yeah...I am old enough to remember that one too. Now I am going to be thinking of that song all day  >:(

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Perry on January 31, 2018, 12:49:00 PM
That is an art! Will you power it with electric motor?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 31, 2018, 04:09:36 PM
Perry,

Derek Hugger recommends a maximum speed of ~ 7 rpm on the input shaft.   With an 8:1 gearing that means the entire cycle of the motion will be about 53 seconds.  Until I finish the assembly and figure/build the counterweight, I won't know how much torque is needed at that speed.  I expect it to be greater than the 3.5 inch-pounds max he gets on the wooden version.

I purchased an air-operated gear head motor at CF that might work.  It's speed is a function of air pressure and flow, so it would allow an easier way to display it in action at model shows.  Whether it has sufficient torque at low speed is the question.   JL's experiments with 12V gearhead motors is also interesting if the model can be operated on battery power.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on January 31, 2018, 11:44:33 PM
I spent today's shop time finishing the spacers for the input shaft as well as shortening a few of the cross tubes  that keep it all together.  I noticed some extreme backlash in the two lower cams, and since the shaft and gears are all turning together rigidly, it seems that the grub screws in the eccentric disks aren't holding properly.  I am going to need to remove the cams anyway to orient them properly according to the plans, so I'll take it a step further and remove the hypocycloids to check the screws and their seating on the flats milled in the axles.  Since the holes for the screws are deep, I might put a second one in on top of the first, or use thread locker.

I have three more CNC pieces to make as well.

One worry I have now, based on holding the pivoting frame, is the amount of weight needed for the counterweight.  I hope it's not so much as to make the piece ugly.  Of course I could try to source the heaviest metal: tungsten.  Or possibly a spring support underneath.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: ShopShoe on February 01, 2018, 01:01:17 PM
A Post of Diversion?

Just my brain going off on a tangent again:

"...way to display it in action at model shows."  I would vote for some kind of electric motor or actuator so that you could have some way it might be automatically activated as viewers came by. I can see it sitting on the table, then suddenly going into motion as a viewer came close. Enhanced WOW factor. Add one of the cheap digital noisemakers concealed somewhere...

No intent to butt in and a tip of the hat to a wonderful piece of mechanical art. I've been following this project and find it fascinating.

Thank You for posting,

ShopShoe
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 02, 2018, 10:55:55 PM
I decide to put my worries about the counterweight aside and worry about the stock market instead.  Of course that didn't help either, so I'll just keep plugging along and see how it works out.

Today was for fitting the two brass "hummer mounts" to the frame along with the wing frame.  A tight fit on everything here is required, so a good bit of fettling was necessary to get everything in position.  Then I could make the pivot tube for the assembly, mill some grub screw flats, and fit the spinners.

(http://www.pbase.com/kvom/image/166952818/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: zeeprogrammer on February 02, 2018, 11:37:28 PM
I decide to put my worries about the counterweight aside and worry about the stock market instead.  Of course that didn't help either,

No point worrying about things one can't control.  ;D

Love the picture. Looking really good!  :ThumbsUp:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on February 03, 2018, 12:29:35 AM
Seeing all the pieces together only makes it all the more impressive Kirk. Really nice work throughout. Looking forward to the maiden flight.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 03, 2018, 12:35:44 AM
Seeing all the pieces together only makes it all the more impressive Kirk. Really nice work throughout. Looking forward to the maiden flight.

Bill
Agreed!


Seeing it come together shows the size too, I was thinking it was a lot smaller.


 :ThumbsUp:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on February 03, 2018, 02:52:36 AM
Kirk,
It's looking good, I'm starting to think that building an engine would be much less complicated. :lolb:
Cletus,
I have to admit that looks all to familiar, and reminds me of my dear old departed Dad. He liked both kinds of music country & western, and the other one polka. I've mostly done pretty good avoiding them and acquiring my own taste in music.
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 04, 2018, 12:50:47 AM
Not as much shop time today as we went to play trains at the club and have lunch.  Our new dog behaved himself with a small crowd, which was part of the exercise.

I finished the last CNC piece and did the next 2 stages of the assembly.  The "back" piece was 3/8" thick, but the brass mounts are only 5/16 apart because they have to grip the frame.  I didn't want to trim the entire length because the head attached to the top end, and it's 3/8.  So I took some off at the bottom just enough to squeeze between the mounts,

Then the next stop was to attach the right side of the bird to the mount and then to add the cam follower for the body,

(http://www.pbase.com/kvom/image/166957268/large.jpg)

For the next stage of the assembly, I need to reassemble the tail (which were the first parts I made at the start of the project), attach the left body part, and add it all.  That's a job for another day.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Perry on February 04, 2018, 08:38:37 AM
 :ThumbsUp: Fantastic!
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 04, 2018, 07:34:30 PM
This morning I reassembled the tail mechanism, this time fastening the bearing shafts with loctite after a test of the operation.

IQTQIBTpThw
Then with the left side of the bird attached to the tail, the combined assembly was added to the sculpture, along with the cam follower.  Following that, I added the head and its cam follower.

(http://www.pbase.com/kvom/image/166961439/large.jpg)

I found a couple of issues that will require some disassembly, but nothing too serious.  The weight of the mechanism continues to concern me, as after all the transmission of power boils down to some 1/16" steel pins being pushed by nylon.  And as well, another "fuse" is the holding power of 8-32 grub screws on flats of shafts.

I also found myself short one needle bearing for the wings.  Looks as if the shop gnomes have hidden it away.  I'll give it a day or two to show up before having to order another.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 04, 2018, 08:25:30 PM
Looking very good!

And leave a plate of cookies out for the shop gnomes, maybe they'll bring that bearing back...
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 05, 2018, 08:35:51 PM
Although the assembly instructions show assembling the "bird parts" to the frame as a series of steps, once they are all in place it's clear they can be removed and installed as a single unit by removing the spinners and the shaft they turn on.  I was having issues with the cams getting out of sync, so with only the frame and cams it's much each to try to get them straight. 

Part of the problem seems to be the rods that connect the gears to the eccentrics.  I made them from drill rod, and it seems that the inside is soft enough that the grub screws deform the flats and allow things to wobble.  The plans call for 303 stainless, and according to McMaster's order history I should have some, but in fact it's nowhere to be found.  Shop elves?  So I ordered another foot plus a replacement roller bearing bearing, and will get back on it when they arrive tomorrow.  In the meantime I still need a bit of fettling on the wings to free up the rotation.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: gbritnell on February 05, 2018, 08:53:09 PM
Absolutely gorgeous! My friend and I bought the drawings when we first found out about it. He finished his in various woods and has a video of it on Youtube. Me on the other hand have had so many projects that I haven't gotten around to this one yet.
He runs his with a small gear head motor driving the hand crank mechanism.
gbritnell
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 05, 2018, 09:19:45 PM
Bird on a vise --

(http://www.pbase.com/kvom/image/166968863/medium.jpg)

In thinking more about the weight issue and having exercised the various motions by hand, I think the issue are as follows

- The counterweight balances the entire pivoting assembly at the top of its rise.  So the bottom cam will have some force at the low points that will decrease as the assembly rises.  That may not be as much of an issue as I feared, and can be tested before putting Colibri on a severe diet.

- The cam for the head has a quite small range of motion and only moves the head up and down, so that isn't an issue.

- The cams wheel for the body and tail work together, since the tail is connected to the body, and both need to resist the tail's weight as it pivots.  The tail cam follower especially has the cam quite far from the tail so that the lever arm is long.  Plus the cam itself has two quite sharp ramps that the follower must climb.  This leads me to believe that I'll need to reduce the mass of the tail assembly.  The brass rack and gear could be changed to lighter material, so that may be the path to take if it proves necessary.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 05, 2018, 09:53:27 PM
With regard to checking the weights balance, I decided to create a temporary counterweight to verify my theories.  To that aim I started doing some internet searches for lead shot.  Not surprisingly, on eBay the shipping costs for lead can be high.  I discovered that one of the ways to buy it is as scuba weight bags, a mesh bag filled with shot.  I checked locally, and I can get a 5lb bag for about $25, so that's my plan.

The way the instructions state for creating the counterweight is to suspend a jar from the counterweight flange by a string and fill the jar with shot (or bbs) until Colibri is balanced, then weigh the jar and shot.  Should make it easy to experiment.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 05, 2018, 10:21:01 PM
Another local source for lead shot is the sporting goods store, they sell bags of shot for reloading shotgun shells, though its usually in large bags. Or, musket balls in the black powder section, come in boxes of 50 usually. Either can be melted down and poured into ingot form to save space. For my clock weight tubes, got a bunch of leftovers from a friend who casts bullets, he had some lead that was a bad alloy. Used to be able to get used wheel weights, but those are going to stick on steel.
On ebay you can get big boxes of the steel weights for verh little money. We use them for submarine ballast.


Anyway, bird is looking great!


Do the cam followers have ball bearings on them to reduce friction?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Vixen on February 05, 2018, 10:28:42 PM
Hi Kirk, After your 'bird on a vise' here is my Petite Colibri 'a bird in the hand' If you look closely, I have added an eye.
Now you are getting to the really exciting part.

Mike  :popcorn: :popcorn: :popcorn: :popcorn: :popcorn:

(http://lister-engine.com/coppermine/albums/userpics/10013/P1050478BB.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: mklotz on February 05, 2018, 11:06:43 PM
Another local source for lead shot is the sporting goods store, they sell bags of shot for reloading shotgun shells, though its usually in large bags.

I bought a bag of #9 birdshot and it's had many uses around the shop.  Makes great dead-blow hammers and a leather bag partly-filled is a great self-shape-adjusting weight when gluing.  In addition, small parts dishes...

http://www.homemadetools.net/forum/small-parts-cups-32173

and a book-holder-opener...

http://www.homemadetools.net/forum/book-holder-opener-28889

Also, bird shot is amazingly uniform in weight.  You can construct precise weights by establishing an average weight and then just counting shot to get to a predetermined weight.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 06, 2018, 07:45:49 PM
I went to the dive shop this morning and purchased 3 bags of shot - 5, 3, and 2 pounds.  I mounted the bird back on the frame and placed a small plastic bucket over the counterweight arm.  The balance point is between 5 and 7 pounds as the 5 pound bag didn't tip Colibri over, and the 5+2 bags did.

Even with just the 5 pound bag the effort to do a complete cycle of the lower cam wasn't too high, so that's encouraging.  I had left a good bit of the mechanism off for this test pending delivery from McMaster this afternoon.

Doing some rough calculations, a 6 pound lead counterweight in a 2.5" diameter round bar (size of flange) would be about 3" long, so not unreasonable.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on February 07, 2018, 02:17:00 AM
Kurt,
Still following along. I wouldn't have thought of diving weights but I did give my uncle two bags of lead shot that I figured he'd use in his black powder guns. They were in the house when we bought it.
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 08, 2018, 12:01:39 AM
Today I added the wing "arcs" to the spinnders, and attached the heim joints to the arch.  The enabled me to check out the wing motion without any other part of the mechanism engaged.  I found a few sticky spots, and some misalignment due to some sizing of a couple of spacers.  But otherwise the wings do move in an interesting manner.

(http://www.pbase.com/kvom/image/166978254/large.jpg)

Then I remade the axle for the top gear and wanted to try the cam followers for the head and tail.  The head cam, as expected, has very little motion by itself and doesn't seem to present any issues.  When I installed the followers for all three cams together I got resistance.  Back to individual followers, I found that the tail cam by itself works well enough that the weight of the tail isn't as big an issue as I expected.  I could turn the input gear and drive the tail through its cycle without excessive force. 

I did notice that there's the same issue as with the wooden version in that the follower doesn't fall down as the cam would lower it; in other words, the bearing loses contact with the cam.  Hugger suggests adding a small weight to the inside of the follower near the "head".  When I applied a bit of weight with my hand, it seemed that the follower action was jerky as the bearing essentially falls onto the cam surface.

Next time out I'll try to find why there's interference between the body and tail followers/
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Brian Rupnow on February 08, 2018, 01:20:17 AM
Kvom--I envy your incredible talent. That is just beautiful.---Brian
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Perry on February 08, 2018, 06:38:00 AM
Eye pleasing!
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 08, 2018, 11:44:11 PM
About to disassemble the bird portion to fix a few things as well as loctite the tail assembly that has been just a sliding fit for testing.  Remade the lower gear axle from 303SS, so all are done,

She loves me, she loves me not ...

(http://www.pbase.com/kvom/image/166982735/large.jpg)

I need to order some screws to complete the flower assembly , but did mount the stem.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 13, 2018, 02:36:52 PM
After a few adjustments and reassembly, I tested the counterweight again with the scuba weights.  At 8 pounds things seemed decent (i.e., I could crank through the cycle by hand without too much torque needed) and at 10 pounds Colibri tipped over.

I had contacted Mars Industries about a sash weight, but they replied that they have a $500 minimum order.  Then I found RotoMetals who sell round lead disks.  I ordered 3 disks 3" diameter by 1" thick (2.89 lbs each).  I'll skim turn these on the lathe and join with a long 8-32 screw through a center hole.

Now waiting on some screws from AME to finish off the flower.

I'm also going to try running it via a battery powered screwdriver I have that may be slow enough with enough torque.  I'll need to whip up a coupler.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 14, 2018, 05:15:52 PM
Screwdriver is too fast and too weak.

I disassembled the air-powered motor I got at CF to see if the reduction unit and turbine could be separated cleanly.  They do come apart, but the input to the reduction unit is the splined shaft of the turbine.  To use the gearbox I'd need to make an equivalent with 12 splines on a .300" diameter shaft.  Gearbox is 15:1, so input for 7 rpm would be 105 rpm.

In the interim, I decided to gamble $14 on a 7 rpm DC gearmotor via eBay.

Waiting on post office for lead weights and screws to finish build and test for real.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 15, 2018, 11:46:05 PM
The Colibri plans call for a "crank" on the input shaft that's just a 2" diameter disk.  It's OK for turning the mechanism slowly, but almost impossible to do so smoothly.  Why searching for a motorized solution, I came up with this temporary manual idea.

(http://www.pbase.com/kvom/image/167010979/large.jpg)

1/2" hex brass rod 1" long.  Drill .251" hole 1/2" deep plus a 8-32 tapped hole for a grub screw 3/8" from the opening.  This fits over the end of the input shaft replacing the disk crank.  Then using a speed wrench with a 1/2" hex socket, the shaft can be turned with pretty good control of the RPMs.

(http://www.pbase.com/kvom/image/167010980/large.jpg)

The lead disks I ordered came in the mail today.  They have decent regularity as to diameter and flatness.  I faced the mating sides and drill a 1/4" center hole through each, then assembled on a brass rod with lots of loctite 620.  After a few hours of cure, I could mount on the lathe to skim turn.

(http://www.pbase.com/kvom/image/167010981/large.jpg)

Finish isn't bad (didn't get a pic afterwards).  Total finish weight is 7 pounds 1 oz according to my kitchen scale.  The 3" length is such that the counterweight probably hits the table at Colibri's maximum angle.  I'll need to measure, but the permanent base is 3/8" thick with a gap in the center, while my temporary base is 1/4" with no gap.  I probably need to remake the counterweight arm 1" longer and at a higher angle than the current one.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on February 16, 2018, 12:08:40 AM
How was the lead to machine Kirk? Just curious as I have never machined any?

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 16, 2018, 12:17:54 AM
Very soft - chuck jaws left depressions in the sides.  The insert I use for aluminum left a smooth finish.  Drilling the holes gave continuous stringers in the drill flutes.  Skim turning and facing left very fine, fluffy swarf.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 16, 2018, 01:03:21 AM
A lot will depend on the alloy, impurities, etc. Only 'machining' I ever did on any was drilling holes for bolts to hold some lead blocks in place in a boat.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 16, 2018, 01:58:44 AM
According to supplier it's 99.9% pure.

Purer than Ivory soap but still doesn't float.   :shrug:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 16, 2018, 02:06:16 AM
According to supplier it's 99.9% pure.

Purer than Ivory soap but still doesn't float.   :shrug:
Just flashed back to Monty Python and the Holy Grail, "what else floats?"  "Very small rocks?!"
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 16, 2018, 10:56:08 PM
My brass 2-56 screws came in from AME go I was able to assemble the flower.

(http://www.pbase.com/kvom/image/167013931/large.jpg)

I also did some measurements to determine how far above the table the counterweight would be at full Colibri height.  It appears that the current weight  (7 lbs) would just fit.  While 8 lbs doesn't tip Colibri backwards, operating it with 7 lbs doesn't seem to require any significantly greater force.  So I'm going to go with that for now.  Here's the weight after turning.

(http://www.pbase.com/kvom/image/167013932/large.jpg)

I suppose a coat of black paint wouldn't hurt.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 16, 2018, 11:05:33 PM
The flower looks great. It needs an oil dispenser to feed the hummingbird...
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Perry on February 16, 2018, 11:22:07 PM
What a nice model that will be  :ThumbsUp:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on February 17, 2018, 12:19:23 AM
Looking great Kirk. Can't wait to see it in motion.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 19, 2018, 05:25:32 PM
I wrapped the outer circumference of the counterweight with some steel (.004") sheet, secured with epoxy.  I figured the less skin contact I have with lead going forward the better.

(http://www.pbase.com/kvom/image/167027835/large.jpg)

The length of the counterweight seem just short enough to clear the table at its lowest point by a whisker.

My motor is at the local post office awaiting delivery tomorrow around noon.  It will be interesting to see if it has sufficient torque to operate Colibri.  Derek's notes recommend a synchronous AC motor.  There are several of these with 6W power and 5-6 RPM on eBay, so that's another option.  Of course, AC isn't often available at shows, although I did see some overhead outlets at CF. 
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on February 19, 2018, 06:07:31 PM
Good idea to encapsulate the lead. On my model boats I like to give the weights a coat of epoxy - ugly, but its usually inside the hull out of sight.

Looking forward to seeing it all go - hope the motor works out!
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 23, 2018, 03:29:27 AM
I received the DC motor earlier this week, cobbled up a coupling, and attached it to Colibri.  Using a 12V battery charger for power and holding the motor by hand from turning, I determined that it appears to have enough torque to drive the complete cycle.

(http://www.pbase.com/kvom/image/167042904/large.jpg)

Next time in the shop I will make a motor mount I drew up in Solidworks to attach the motor to the side fame.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 23, 2018, 11:17:42 PM
The eBay page for the  motor contained a dimensioned drawing of the motor exterior, so it was simple to draw up a mount in SolidWorks and then machine it on the CNC mill.

(http://www.pbase.com/kvom/image/167046256/large.jpg)

Attached to the motor with the only M3 screws I had on hand.

(http://www.pbase.com/kvom/image/167046257/large.jpg)

To secure it from rotating around the shaft, the hole in the tail aligns with the spreader rod holes in the support frame.  Now I just need an extension to the rod to attach the motor mount.

(http://www.pbase.com/kvom/image/167046258/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 24, 2018, 09:41:15 PM
After a bit of shopping at Fry's for electrical stuff, I machined the extension for the spreader and mounted the motor.  Tests with the 12V battery I acquired today went well (no magic smoke escaped), so hopefully the next job of connecting the small toggle switch I also bought will allow the power part of the model to be considered complete.  Then I just need to reconnect the wings in order to get a video made.

(http://www.pbase.com/kvom/image/167049453/large.jpg)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on February 26, 2018, 11:53:47 PM
Had a snag in progress today.  I was running it with the motor to get to the point needed to position the wings properly when I noticed that the top cam wasn't turning.  After some disassembly I found that the axle was bent jamming the cam.  I made a new axle and verified that there were no jams before replacing the gear.  All seemed well until it did the same thing.   :cussing:

Now I don't have any more material for the shaft and need to order more.  Next time out I'll remove the motor and turn with the wrench to see if and where it happens. 
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 01, 2018, 09:30:52 PM
After remaking the top gear shaft, I reassembled for a beauty shot.

(http://www.pbase.com/kvom/image/167073529/large.jpg)

There is still intermittent sticking.  If the motor is running it, then there's enough torque to break the shaft when it sticks, so I've been moving the input gear slowly by hand trying to diagnose the issues.  The fact that the base is temporary prevents Colibri from pivoting as far forward as it should.  I have a big piece of stock enroute on a UPS truck, so I may not do much with it until I can make the proper base.  The tail follower flexes too much from side to side, and that may be an issue to look at.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on March 01, 2018, 09:50:00 PM
That is a real beaut!

Have you shared this build with the original designer?
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 01, 2018, 10:08:26 PM
I'm going to wait until I have good base and can produce a video with the motor running.  He's aware I'm doing the project.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on March 01, 2018, 10:33:29 PM
It looks great Kirk!! I am sure you will track down the bugs and have it running soon.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: zeeprogrammer on March 01, 2018, 11:38:50 PM
I'm going to wait...

Re: posting a current video. Bummer. Understandable. But bummer. It's a very neat project.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 06, 2018, 01:25:34 AM
Managed to make the tail follower less floppy by gluing the brass spacer to the frame.  It's being loose allowed the shaft to flex a bit too much.

(http://www.pbase.com/kvom/image/167094444/large.jpg)

I also added some 1/2" hex brass rod to the right side of the input shaft, allowing me to operate Colibri with the speed wrench while being able to see the cams and followers.  I cycled it a couple of times without any jams this way.

(http://www.pbase.com/kvom/image/167094445/large.jpg)

Material for the base should be here this week.  I remounted the vacuum chuck on the CNC mill, and measured it flat to within .001" across the surface.

Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 08, 2018, 09:30:29 PM
I got the base finished over the past two days.  Stock was a 14.375" diameter disk of Mic 6 cast aluminum, 3/8" thick from eBay.  Machined most of it away on the CNC mill using the vacuum chuck for workholding.

(http://www.pbase.com/kvom/image/167108405/large.jpg)

I replaced the temporary base with this one after deburring.

(http://www.pbase.com/kvom/image/167108406/large.jpg)

I hope to get a video posted before too long, but Colibri construction is essentially finished.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on March 08, 2018, 09:41:08 PM
Nice base!


Have the recent tweaks solved the problem with that shaft breaking?


 :popcorn:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on March 09, 2018, 12:19:43 AM
If it runs as good as it looks (which I suspect it will), the video will be a real treat!!  Lovely work!!!

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 09, 2018, 12:51:26 AM
I discovered that the shaft problem results from the counterweight touching the table at a point where the bird still needs to rise slightly.  It appears that on a flat surface the weight causes the entire base to tilt back very slightly eliminating the small clearance that exists with the base flat.  If the weight is positioned over the edge of the table all is well.  Adding some weight to the front may solve the problem, or else a sub-base.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on March 09, 2018, 01:04:31 AM
I am assuming that the reduced weight of the wood version and a resulting smaller counter-weight didn't factor in as much as far as required clearances in the original design. Seems you have the issue sorted out though.

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 09, 2018, 01:44:14 AM
The counterweight is much larger and heavier.  The length of 3" was only possible by using lead, whereas the wood version uses a brass or steel weight.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: kvom on March 16, 2018, 10:31:47 PM
After 5 days is Las Vegas, I got back in the shop today to make the first video of Colibri in action.

cHDfKOT-6tE
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Vixen on March 16, 2018, 10:38:30 PM
I still think that Colibri's wing/shoulder joint and mechanism is most graceful and artist piece of mechanical design..... ever.

Mike
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: crueby on March 16, 2018, 11:00:37 PM
Very very nice!   :ThumbsUp:
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: b.lindsey on March 16, 2018, 11:55:24 PM
Wonderful Kirk. Seems to be relatively smooth throughout the entire cycle and the metal and acrylic nake for a very nice contrast. Well done!!

Bill
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Steamer5 on March 16, 2018, 11:59:04 PM
 Very nice!
Mesmerizing to watch.

Cheers Kerrin
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Art K on March 17, 2018, 03:45:54 AM
Looks great Kirk.
 :cartwheel:
Art
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: Kim on March 17, 2018, 04:59:12 AM
Very nice Kirk!  That's truly a great piece of art!

Kim

PS  I can even hear a bird chirping slowly in the background! :)
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: ShopShoe on March 17, 2018, 01:08:39 PM
I've been waiting for the video of the sculpture in motion. It's better than I imagined.

Congratulations on the the completion of this intricate and beautiful piece of art.

--ShopShoe
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: zeeprogrammer on May 01, 2018, 10:56:41 PM
I remembered tonight I was following this and waiting for the video.

Very nice! Truth be...a lot more people will enjoy this over a steam engine.

 :ThumbsUp: Nicely done.
Title: Re: Colibri Hummingbird Dynamic Sculpture - WIP
Post by: KB on May 02, 2018, 04:13:34 AM
So nice, very well done.

I love the fluid mechanicalness of it all.