Elmer's Grasshopper

[RReid]

My “other” current project, or the one that is most being worked on currently,  is Elmer Verburg's “Grasshopper Engine”. The cylinder of this one is fun because it incorporates round flanges on the ends with flat surfaces in between. A good exercise for both the lathe and the new mill, and visually interesting. I'm not straying from the plans at all, except for adding some reliefs to the beam to bling it up a little, and trying Delrin rather than aluminum for the piston. Oh, and I screwed up the location of the center cross brace in the column. Should be able to work around that, I think it's mostly cosmetic anyway. Here are a few pics of the progress to date.

[RReid]

Elmer's drawings show the upper end of the column and the two bearing blocks being radiused. This morning I experimented with using the lathe headstock as a simple manual rotary table. Credit for the idea goes to Keith Brooke, as posted on Nick Carter's excellent Taig-centric website. Seemed to work pretty well. Down milling is to be avoided for any but the lightest cut, but up milling is no problem, within reason. A spindle brake/lock would certainly be a help. I used the 4 jaw (with one jaw removed) for the experiment, but will probably clamp the real parts to a faceplate.

[Kim]

That's a very interesting use of the headstock and the milling attachment! 

I'm a Taig owner myself.  I started with just the taig lathe about 10 years ago.  Then got the Taig mill, and a few years later got a bigger lathe, then a couple years back got a bigger mill.  I don't use my Taig setups much anymore, but still have them just in case!

Very nice work on the Grasshopper - that's going to be a nice engine too.

Kim

[EricB]

Ron,

Nice work so far!

It's a common practice (with Sherline tools anyway) to use a second headstock for indexing. I would want some type of positive control of the spindle to try and cut an arc.

Be sure to place a shim under your stock so you don't crash into your chuck or faceplate.

Eric

[RReid]

a few years later got a bigger lathe, then a couple years back got a bigger mill.  I don't use my Taig setups much anymore,

I promise not to hold that against you Kim. 

Thanks Eric.

[RReid]

Been whittling away on Grasshopper parts. Using the lathe headstock as a rotary table worked OK, but without any positive stops or even means to increase the rotating friction, it was tricky working up to those little shoulders. I got it close, then finished off with files. (photo 1)

Also got the bearing blocks and the crankshaft done. The Allen screws are acting as set-screws for the bushings, and are temporary stand-ins. I plan to make a couple of little brass oil cups to go in their place. (photo 2)

The plans call for notching the steel base for the upright arm that pivots on a pin and supports that end of the beam. I decided instead to make a separate aluminum bit to serve that function. Faced it to dimension on the lathe, then notched it and drilled it part way on the mill with a 10-32 tap drill. Then I clamped it to the base plate and drilled through into the base on the drill press, after which the hole in the ali part got clearance drilled. (photo 3)

That upright arm also gets a squared notch at the top to receive the beam. Here's the wrong way to set that up. This didn't look rigid enough to me, and so it proved. (photo 4)

Here's the better way. (photo 5)

Followed by the vertical set-up just to square off the bottom. I also realized that I could drop the part down into the table slot, reducing the height above the top of the angle plate. This worked fine. (photo 6)

That upright arm will be getting some cosmetic openings cut into it, but here is how it all looks so far. (photo 7)

[propforward]

That engine is coming along really well. You are making very nice components.

[RReid]

Thanks Stuart!

One handy little accessory I ordered along with my milling machine is the little fixture shown below. It's threaded 3/4-16 to match the Taig lathe spindle nose and bolts to the mill table. I don't imagine it's a Taig original idea, and many of you probably already have something similar, but if you don't you might want one! Being able to move the chuck or collets from lathe to mill table and back without disturbing the part set-up, or just moving parts between mounted collets as shown here, is really convenient sometimes. (image

The part I'm working on the upper fork for the connecting rod between the crank pin and the beam. I'd already mounted the bar in the 4 jaw and turned a ¼ in spigot for the 5-40 threaded portion. That was used to mount it in the collet above, then back to the lathe to drill and tap. (image 9)

To round of the end I went old school. I parted off a piece of ¼ rod to be a snug fit between the jaws and used that as a filing guide. Started with a mill file and finished with needle file and wet/dry paper. (image 10, 11, 12 13, 14)

On to the next thing...

[crueby]

Ron - the images/videos/whatever they are in that last post are not coming through, just showing as an odd symbol. Not marked as public or something maybe?

[RReid]

Thanks for letting me know Chris. I can see the images, so I thought I had it. I'm trying to use Google Photos and I have an idea what's wrong, but if that doesn't work I'll go back to attaching the pics at the end for now.

[crueby]

Are you using the Share button and Create Link to get the path to the photos? You can't just take the URL from when you are viewing the photo in Google Photos, that is just available to you.

[RReid]

Are you using the Share button and Create Link to get the path to the photos? You can't just take the URL from when you are viewing the photo in Google Photos, that is just available to you.

I used Copy Image Link which gave me images in the post that I can see, but I can understand why others don't. I had tried the Share button and Create Link earlier, and again on your suggestion, but that doesn't give me any images in the post at all. I'm using the Insert Image button in the post editor. What am I missing?

[RReid]

Redo:

Thanks Stuart!

One handy little accessory I ordered along with my milling machine is the little fixture shown below. It's threaded 3/4-16 to match the Taig lathe spindle nose and bolts to the mill table. I don't imagine it's a Taig original idea, and many of you probably already have something similar, but if you don't you might want one! Being able to move the chuck or collets from lathe to mill table and back without disturbing the part set-up, or just moving parts between mounted collets as shown here, is really convenient sometimes. (image

The part I'm working on the upper fork for the connecting rod between the crank pin and the beam. I'd already mounted the bar in the 4 jaw and turned a ¼ in spigot for the 5-40 threaded portion. That was used to mount it in the collet above, then back to the lathe to drill and tap. (image 9)

To round of the end I went old school. I parted off a piece of ¼ rod to be a snug fit between the jaws and used that as a filing guide. Started with a mill file and finished with needle file and wet/dry paper. (images 10, 11, 12 13, 14)

On to the next thing...

[crueby]

Are you using the Share button and Create Link to get the path to the photos? You can't just take the URL from when you are viewing the photo in Google Photos, that is just available to you.

I used Copy Image Link which gave me images in the post that I can see, but I can understand why others don't. I had tried the Share button and Create Link earlier, and again on your suggestion, but that doesn't give me any images in the post at all. I'm using the Insert Image button in the post editor. What am I missing?

Maybe google photos doesn't allow themselves to be used as a photo host for forums? Not sure, I use PostImage for mine. Anyone else use google photos for thier posts here?

[joe d]

Coming along nicely, Ron.  I've not seen that collet fixture for the Taig mill before, I need one of those!

Cheers, Joe

[RReid]

Thanks Joe. Taig part #1221.

Thanks for the help Chris. I'll check out PostImage.

[steam guy willy]

Hi, as have an Apple I take the photos on my SD card ..then import them and after editing them I file them into " Documents" and then they will come up when I press "Attachments"....
Willy

[RReid]

The links that connect the beam to the fixed vertical column are simple, but also pretty plain as drawn. I thought I'd add a relief to them similar those in the beam itself, to spiff them a little.


I clamped a piece of scrap ali to the mill table and drilled it to match the holes in the links.


That way I could mount the links over pins and be sure the cutting is uniformly in line each time.


I think the result looks much better.

[RReid]

To avoid potential confusion with the "other" Ron on the forum, iRon, who has been here longer than me, I have changed my signature to Ronald.

[crueby]

I like the extra details in the sides, adds a lot.

[RReid]

There is a great combination hardware story, pipe and metal supply, and salvage yard in one of the neighboring towns near me. The salvage yard is the main draw for me. It covers several acres and is an absolute scrounger's delight. Unlike many such places it is somewhat organized, much of the stock is on shelves inside open sheds, and you are free to wander all you want. Like a good bakery or sweet shop, it's probably just as well that it is not quite close enough for me to just casually “pop in for a look around” whenever I want.

I went down there the other day looking for potential stock for the Grasshoppers flywheel, which should be at least 3” x 1/2”  (76x13mm) and found a 3” cast iron caster wheel. The diameter is just right, but it's too wide and has a worn out ½ inch bore where I need a ¼ inch bore. Perfect! I also picked up a slightly larger piece with “future project” written all over it.


Since the a 3” diameter won't clear my cross slide I had to reach across with a right cutting tool to reduce the width. I cut back the first side chucked on the OD, as well as skimmed the OD and trued up the hub.



Then I turned it around, chucking on the hub, and brought it to the final width. The hub on that side was shortened to be flush with the outer edge of the wheel, and the bore opened up to 9/16” (14mm) for a sleeve I made from steel rod.


A few pictures of the end product. That extended hub looks the business for a flat belt PTO, and I left most of the “meat” on in case I want to reduce the diameter or cut a groove for a v-belt or o-ring later. I know the wheel  should really be spoked, but I'll wait until I acquire a proper rotary table to do that job. At least it looks OK as is.

[crueby]

Nice find, looks great on the engine. Sounds like a fun toy store, I mean salvage yard!

[Don1966]

 ….. 



 
Don

[RReid]

Thanks guys. And Chris, thank you for tipping me off to Post Images, that's working well for me.

[bent]

Looks good to me!  No need for spokes...

[RReid]

The last couple of days were spent mostly tying up some of the little loose ends that accumulate during a build. The biggest of those was getting the cylinder assembly located, fastened to the base, and connected to the beam. It's fastened to the base with four 5-40 machine screws cut from 3/16 hex brass. When I made that die holder I started to skim the OD, then realized, not having a knurling tool, that it'd probably be easier to grip with the mill finish.




The base was tap-drilled using the already drilled cylinder base as a template. The tap wrench I'm using was my great-grandfather's. The other one shown was also his. I have no idea how old either one is, but they both get lot's of use. I never knew him, he passed before I was born, but I imagine he'd be pleased they're still in use.




Still ahead are the steam chest and all the valve and valve motion parts. Before that though is vaccine jab #2 tomorrow morning.

[90LX_Notch]

Looks great Ronald.  You’re getting close.

-Bob

[RReid]

Thanks Bob.

Got a start on the valve related components today. Used my 9” bandsaw to take a slice off a piece of 3/4” square brass (can you tell that's an after the fact staged photo?).


The thin piece will be used to make the steam chest and the big-end of the eccentric strap. The main focus today was to turn that stub of 5/8” mild steel into the eccentric.


That went fine until almost the last step. After skimming the larger diameter, I swung the tool over to chamfer the edge. I made sure the tool was clear of the smaller diameter and started the lathe. At that moment I realized my mistake. The smaller diameter is offset and it's not going to clear for long!
Luckily I switched off almost as soon as I switched on, so the only result is a minor scratch. Whew!

Normally I turn the spindle by hand first to ensure all is clear, but that time I didn't. I was thinking maybe I could report dumb-headedness as an after effect of the second Covid shot, but in reality it's a pre-existing condition.

[RReid]

The eccentric strap for this engine consists of two parts, a 3/16” big end bored to fit the eccentric, and a 1/16” thick strap that reaches over to connect to the valve rocker. This seemed to be a part that didn't really want to get made. Lots of experimental techniques that didn't yield positive results, i.e. mistakes, goofs, and foul-ups.

The big end started as an oversized rectangular block. This was soldered to a scrap of brass rod to make it easier to hold in the 4 jaw chuck. In the first pic you can see the off center center punch...


used for locating the part in the lathe on the bore center line with the help of my wobble stick...


so it can be drilled and bored...


to fit the eccentric.


Here big end and the strap have been soldered together and the strap portion is being profiled. The center has already been fluted.


Overall it ended up OK, but not my best work ever.


I was happier with the first of two oil cups for the crankshaft bushings I made at the end of the day today. Now I just have to make a second one that matches!

[joe d]

That came out really nice.  I do like the flywheel as well

Joe

[RReid]

Hi Joe. Thank you for the encouraging words.

Today I started by making an oil cup for the other crankshaft journal to match the one made yesterday.


Then I moved on to the “valve crank”.


After I reduced the bar I started with to size and drilled the two holes, I tried something different to round over one end. In an order for some odd and ends, Taig mistakenly sent me their radius turning tool rather than one of the things I actually ordered. OK, similar value, so rather than make a fuss I kept it and ordered the bit I really wanted later. I clamped the radius tool in the little mill vise and a small diameter Dremel sanding drum in the spindle. With a pin through the part into the swivel of the tool, it was simple to swing the stock against the sanding drum, advancing the table a bit each time. It did help that the stock wasn't cut to final length, so it was easy to hold. And less frightening than an end mill.


Next, I mounted a piece of Al in the 4 jaw, drilled and tapped the center 3-48, then moved the chuck over to the mill to drill a 1/16” hole 7/16” away from center. Back on the lathe, the now cut to length part was screwed and pinned to those two holes.


This allowed me to thin it down to 1/16” for most of the length while leaving a 3/16” boss at the end with the larger hole. I used a brass pin (happened to be brass tubing), so it just got turned down as I went. You can't see it, but it actually is still there in the photo.

[Kim]

Nice series of ops for the valve crank.  One more part down!   
Kim

[RReid]

Thanks Kim. Yep, one part at a time.

Here's one way to kluge a follow rest:

[RReid]

Shop time has been a bit disrupted this week by roofers doing their thing and causing a rain of dust and bits of OSB sheathing in the garage. Been chunking away on valve gear parts when it's not too bad though. The steam chest just needs to be drilled for the mounting studs, and the valve rod still needs a bit of work at the outer end to mate up with the fork shown next to it. Guess I should make the valve next.

[EricB]

Looking good! Clever use of the radius tool too. I wonder if that tool will fit my Sherline. 

Eric

[RReid]

Thank you Eric. As for the radius turner, I don't know, but if it doesn't fit the Sherline as is I'm sure it could be adapted, we being machinists after all!  I was using it upside down, with the tool holder clamped in the mill vice. Here's a catalog picture. In general, as much as I really like the Taig machines, their accessories aren't as nice as those offered by Sherline in my opinion, of which I have a couple.

[EricB]

Sherline's radius tool cost 5 times as much, is much more complex, takes two hands to operate, and puts you dangerously close to the chuck. I can't justify Sherline's cost but I want a radius tool of some type.

I've been thinking of getting a Taig ER-16 adapter so I might get their radius tool too.

I also see in your kluge follower rest photo that you have a Sherline motor on your lathe. The spacer blocks for the mounting screws look much better than the washers they come with. I'm going to have to make that mod too.

Eric

[RReid]

Sherline's radius tool cost 5 times as much, ...

Yes, that is the trade-off, isn't it. Just know that as designed that tool will do a good 180 degree radius, but not much more than that. It is not a full on ball turner.

I do like the ER-16 adapter and use that all the time. Adding the Sherline motor was a bit spendy, but a nice upgrade from a single speed AC motor and well worth it to me.

[RReid]

The Grasshopper is almost complete. I want to paint the steel base, but before taking it apart I wanted to make sure it runs OK. I think I'll leave all the other parts “natural”.

Here's a few photos and a short video. I need to make up a throttle valve for the air line, the trigger on my air nozzle is too sensitive, even at only 10psi. I'm holding it just barely cracked.






<a href="https://www.youtube.com/watch?v=B8qBQvoKT6Q" target="_blank">http://www.youtube.com/watch?v=B8qBQvoKT6Q</a>

[EricB]

 That's a good looking engine! 

You should throw a size reference in the pictures so we can see how tiny it is.

Eric

[Kim]

Congratulations on a runner!  That's always fun to see it working for the first time! 

Now you can go a d paint it knowing that it works!
Kim

[RReid]

Thanks Eric! Thanks Kim!

You should throw a size reference in the pictures so we can see how tiny it is.

I can do that. It's not all that tiny, especially compared to Elmer's "Tiny", the one on a wood base.

[Flyboy Jim]

Congratulations on a fine looking and running engine. 

Jim

[joe d]

Congrats Ron!  Good looking, and a runner too

Cheers, Joe

[MJM460]

Well done Ron.  Always very satisfying to see your creation run.  And it’s an interesting looking engine too.

MJM460

[RReid]

Jim, Joe, and MJM460 - Thanks guys!

[RReid]

I'd wanted to get those previous pictures posted because we were planning to be away for a bit, our first real post-vaccine outing.  After spending a maskless weekend staying with our daughter's kids (Yayy!) so she and son-in-law could have some time away (Yayy!), we took our little camp trailer over to the far side of the Sierra's for a few days camping (Yayy!). Beautiful area, we had a great time being “out” again, just got home yesterday. Here's a few off-topic shots from a side visit me made to the Nevada State Railroad Museum in Carson City.

Now to finish up the last few details on the Grasshopper and move on to the next project!

[crueby]

Oh, to have a shop like that third picture!  Enjoy your time out!

[Kim]

Ron,
Sounds like you guys had a great time!  Glad you were able to get out.  Surprising how much a little outing like that can lift the Covid blues, eh?

Kim

[crueby]

Just the few outings I've done with friends lately has helped a whole lot. Next weekend am up to Maine for the first event at the logging museum driving the gas Lombards, also stopping in the Boston Waterworks museum to see the big steam engines there. Really looking forward to it!

[RReid]

Surprising how much a little outing like that can lift the Covid blues, eh?

Absolutely! And to be able to have my 3 yr old grandson on my lap again to read him a book - Priceless!

Next weekend am up to Maine for the first event at the logging museum driving the gas Lombards, also stopping in the Boston Waterworks museum to see the big steam engines there. Really looking forward to it!

That sounds cool! Have a great time!

[RReid]

I thought I would close out this build with one last video of the Grasshopper doing some totally useless work running the other two Elmer's engines. I like it best at the end as the pressure falls and it runs more slowly. I just wish that table wasn't such an effective sounding board, that knocking is really just a ticking, but I guess it highlights where I can do a little better next time!
<a href="https://www.youtube.com/watch?v=n1fBCVCm1k0" target="_blank">http://www.youtube.com/watch?v=n1fBCVCm1k0</a>

[Don1966]

Awesome……




 
Don

[RReid]

Thanks Don! I was just using your Spur Gear Calcs spreadsheet the other day, very handy. Thanks for that too! For my own use I added a cell to calculate center-center distance of two mating gears from the DP and tooth counts.