Author Topic: Crossley Otto Langen  (Read 1069 times)

Online Craig DeShong

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Crossley Otto Langen
« on: September 03, 2019, 01:16:13 AM »
I built my first Otto Langen Atmospheric engine around six years ago.  It took about a year and a half to build it and another eighteen months to get it to run. :) As the years have passed Iíve learned a lot and have listened to advice given by those who have more experience that I  :old: (such as Wayne Genning) and now with much experience and excellent advice, the engine runs quite well.

Two years ago I was invited to the Rough and Tumble Engineers Association at Kinzers, Pennsylvania to bring my model and help celebrate the 150th year anniversary of their original Otto Lagen: the oldest running internal combustion engine in America.  While I was in attendance, the germ of this project was born.

The Rough and Tumble Engineers Association at that time had on loan from the Henry Ford Museum, their Crossley built Otto Langen.  Two years later, the Crossley engine is still on loan. 

I planned a trip to Kinzers (Rough and Tumble) this past August with the primary objective to get many detailed photos and measurements of the Crossley engine so that I could attempt a model of this engine.

So you can become familiar with this engine, I provide a photo of the engine as it currently resides at Rough and Tumble.


We were all remarking that this engine is an extremely well built machine; the folks at Crossley, way back when, built a magnificent machine.  Below I given you a closer photo of the front of the engine with the builders plate.



And a photo of the sign Rough and Tumble supplies with a few of the engine details.



Also a photo of the Crossley with Rough and Tumble's Otto Langen.
 Two original Otto Langen engines side by side; something you donít often get to see.



I canít speak highly enough about the folks at Kinzers.  They permitted me to get all the measurements and photos I needed.  Needless to say, care for the engine was paramount in my mind as I did this.



Now I know Jo is going to say, ďJeez, canít you build a model with CASTINGS?Ē.  Never fear Jo, Iíve purchased the flywheels already and they are castings. :cartwheel:  I scoured the internet and found these 11 inch flywheels that, when turned down to 10 inches, will very closely resemble the flywheels on the full size.  That makes the model at around 1/6th size.  These flywheels are HEAVY; this thing is gonna coast between hits "forever".



One last picture where I show my progress on the design of this engine.  Itís going to present some unique challenges, but then if there were no challenges, where would the fun lie?



The design is progressing slowly and Iím concentrating on getting the major measurements established.  Once thatís done, Iím thinking Iíll go back and try to make some of the major parts look more like the original casings.
« Last Edit: September 03, 2019, 01:21:08 AM by Craig DeShong »
Craig

Offline Dave Otto

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Re: Crossley Otto Langen
« Reply #1 on: September 03, 2019, 01:21:52 AM »
Interesting project Craig, looking forward to following along.

Dave

Offline steamer

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Re: Crossley Otto Langen
« Reply #2 on: September 03, 2019, 01:36:46 AM »
Nice project!   I'm looking forward to watching this one.

Dave
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Damned ijjit!

Offline cheepo45

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Re: Crossley Otto Langen
« Reply #3 on: September 03, 2019, 01:38:09 AM »
Very cool project, Craig.
Good talking to you at the R+T Museum.
I will be watching with interest.
 Scott

Offline Johnmcc69

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Re: Crossley Otto Langen
« Reply #4 on: September 03, 2019, 02:25:52 AM »
Great project Craig!
 I'm along for the ride.
 :popcorn:
 John

Online Jo

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Re: Crossley Otto Langen
« Reply #5 on: September 03, 2019, 07:12:40 AM »
Now I know Jo is going to say, ďJeez, canít you build a model with CASTINGS?Ē.  Never fear Jo, Iíve purchased the flywheels already and they are castings. :cartwheel:  I scoured the internet and found these 11 inch flywheels that, when turned down to 10 inches, will very closely resemble the flywheels on the full size.  That makes the model at around 1/6th size.  These flywheels are HEAVY; this thing is gonna coast between hits "forever".

 :D

It will be nice to see a model of the Crossley version of the Otto Langen being made.

Jo
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Online b.lindsey

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Re: Crossley Otto Langen
« Reply #6 on: September 03, 2019, 01:29:45 PM »
A wonderful project Craig. I am sure you will do it justice and end up with another fine version of this unique engine.

Bill

Online Brian Rupnow

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Re: Crossley Otto Langen
« Reply #7 on: September 03, 2019, 01:49:21 PM »
Very interesting Craig. I will follow along and watch your progress.---Brian

Offline Alyn Foundry

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Re: Crossley Otto Langen
« Reply #8 on: September 03, 2019, 04:02:30 PM »
Hi Craig.

I too will be following with great interest.

Here's a link to a 3 HP engine, the largest size built by Crossley brothers of Manchester.


Currently installed at the Anson Engine museum near Stockport Manchester.

Cheers Graham.
« Last Edit: September 03, 2019, 07:21:00 PM by Alyn Foundry »

Offline kvom

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Re: Crossley Otto Langen
« Reply #9 on: September 03, 2019, 08:49:05 PM »
Better not underestimate ceiling height with that puppy/   ;D

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #10 on: September 06, 2019, 12:49:45 AM »
Dave, Dave, Scott, John, Jo, Bill, Brian, Graham, Kirk; thanks for stopping by and showing interest in this new project.  I believe itís going to be very interesting as it moves along.

Scott- GREAT to see you too at Kinzers; Iím thinking of making my appearance an annual event.  As I said before; itís a great show with LOTS of interesting people.

Iím glad Graham posted the video above.  You can see that the Crossley version of the Otto Langen fires and the piston immediately returns to the bottom of the cylinder with a governor mechanism that directly controls the escape of the pawl and ratchet.  This is distinctly different that the German built versions, where controlling the escape of the spent gasses controls the next cycle.

With hurricane Dorian slowly moving up the coast itís been a rainy day today, so I spent the day moving forward with the design of this engine.  Iíve finished the governor design and am well into the pawl release mechanism design.  Iíve included a few images of the main assembly for your purview, but itís hard to make out detail from what Iíve given you.  The current design is also probably fraught with errors and inconsistencies.  Designing an engine takes many hours (days).

Iíll be cutting all the gears for this engine, including the bevel gears that drive the governor.  Having never made bevel gears Iíve done a ďtrial runĒ in aluminum and everything came out fine.  Iím using the Ivan Law book and I canít recommend it high enough for anyone who contemplates making their own gear trains.  In a design like this you really need to get all the questionable stuff behind you because itís easy to design yourself into a dead end if you expect to be able to do something and it doesnít work out.

Well, enough blabberingÖ hereís a few images of the design to date.




Craig

Offline Johnmcc69

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Re: Crossley Otto Langen
« Reply #11 on: September 06, 2019, 02:08:16 AM »
Good stuff there Craig!

 Not to derail this thread, but how long have you been running "SolidWorks"?

 I'm thinking about moving away from my current CAD. (PRO-E/CREO)

 JOHN

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #12 on: September 06, 2019, 02:57:53 AM »
Hi John

I'm using Alibre Professional.  I upgraded from "cubify" about a year ago.  I used cubify for around two years previously.
Craig

Online Jasonb

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Re: Crossley Otto Langen
« Reply #13 on: September 06, 2019, 07:00:27 AM »
Craig, are you on maintenance as that does not look like the current version or just running in the old legacy mode?

It's going to be an interesting one to watch, which will you build first this or that upright you drew earlier in the year?

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #14 on: September 06, 2019, 01:42:17 PM »
Jason, Thanks for your interest. 

The Alibre folks sold me a life-time licence for the current version at the time of sale for a very attractive price.  I suspect, as time passes, my version will get a little "long in the tooth".  As a modeler, I can't see needing all the bells and whistles of the newer versions, since they probably concentrate on 3D printing, something I'll never be able to afford.  Down the road it will be interesting to see if a windows update permanently breaks my version and how the Alibre folks will address that.

What do you mean by "old legacy mode?"

I still have the Regal design on the back burner; even have a nice chunk of aluminum set aside for the frame.  I suspect I'll get to it eventually.  My plans are to build the Crossley when I have completed the design.  Making a model of the Crossley Otto Langen has been rattling around in my mind ever since I first saw the full size a few years ago.  It currently has my interest so that is what receives my attention.

This is the first model I've designed with the Alibre product where I'm familiar enough with the tool so that my concentration can remain on designing the model and not be drawn off to concentrating on "driving the tool".  I'm in a mode where I design a few components and then assemble those components into sub-assemblies, then the sub-assemblies into a main assembly.  From there I can take measurements and either "tweak" the existing components as necessary or use that information in the design of more components, building on that principal until the design is complete.  In reality you're building the model, logically, within the computer.  It's a new way of thinking for me.

Also, I'm planning on making a full set of drawings with the intention that someone else (besides me) could build the model using them.
« Last Edit: September 06, 2019, 02:00:38 PM by Craig DeShong »
Craig

Online Jasonb

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Re: Crossley Otto Langen
« Reply #15 on: September 06, 2019, 04:04:18 PM »
The latest version adds shadow and highlights to the parts, not to the same extent that Fusion does though definately not a full render but more than it did upto a couple of months ago. Line weights are also different as well as several other tweaks and fixes.

You can switch these off which is like running the older version in the same way the latest update to Fusion 360 can be reverted to the old look.

I design in much the same way as you doing groups of parts into sub assemblies and then the main assembly going back and forth tweaking fits and sizes, this is how things look now.
« Last Edit: September 06, 2019, 04:11:13 PM by Jasonb »

Online Brian Rupnow

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Re: Crossley Otto Langen
« Reply #16 on: September 06, 2019, 04:29:21 PM »
Nice 3D work guys.I worked the first 30 years of my career on a drafting table. I thought all this computer stuff was just science fiction. Now after 25 years on CAD I wonder how i could have been so naive'.---Brian

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #17 on: September 09, 2019, 11:06:41 PM »
I have heard that the folks at the Smithsonian Institution have an Otto Langen engine that was destroyed through ignorance when they incorrectly tried to run it years ago.

I was at a show this weekend and though I donít recall the series of events that lead up to it; I managed to overcharge my model :hammerbash: and though it didnít blow the piston out through the top of the engine; when the piston hit the flat table above the cylinder so violently the force sheared off a clevis pin holder that attaches the rack to the piston :o and I was out of business for the remainder of the day. :insane:

Today Iíve been making repairs and the model is running again. :ThumbsUp:

While I had it apart I used the opportunity to do a little ďwhat Ė ifĒ in answering some questions I need answered to move ahead with the design of this Crossley engine. :thinking:  The bore of my Otto Langen is a tad over 2 ľ inches and the scale bore of the Crossley would be right at 2 inches so I figured my current Otto Langen ought to fire with the same characteristics as this Crossley model I plan to build.

My existing model lifts the piston around 7/8th inch and the resulting charge provides a stroke of nearly eight inches in height.  This length stroke is way to long for the Crossley if I want to maintain scale so I fiddled around with adjusting the lift height of the piston and measuring the resulting stroke.  When I had reduced the piston lift height to around one half inch the resulting stroke had been reduced to around four inches- much more in line with a stroke length for this Crossley model.

So Iíll be setting the piston lift to around Ĺ inch on the Crossley and this ďshouldĒ allow the scale cylinder height to accommodate the resulting movement of the piston in the bore.  One more issue resolved in the design of this model.
Craig

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #18 on: September 12, 2019, 12:52:23 AM »
The design of this model has been moving along.  Most of what is left to do is cosmetic in nature, so that the model, though made from bar stock, preserves the ďflavorĒ of the original.

Before I get too involved in the time consuming nature of this later design phase I thought I would concentrate on some of the parts of this model which might need design refinement.  Since this design refinement might result in an alter of frame measurements Iím thinking it prudent to address these issues before I get into the final frame design and construction.

One of these issues I discussed earlier up thread was the design and construction of the bevel gears that will drive the fly-ball governor. 

In this photo Iím forming the gear blank, taking a facing cut to reduce the piece to the correct thickness.


The next task was to cut the 45 degree shoulder for the face of the gear teeth.  Iím doing this with the compound slide, having set its angle to the crosshead guide at 45 degrees.  Iím also running the lathe ďbackwardsĒ.


Moving on to the mill.  Here I have my indexing head mounted to the table at 45 degrees in order to cut across the face of the gear blank and form the individual gear teeth.


I failed to provide a photo of the gears I produced so I give it below.  The larger (drive) gear is the final gear Iíll use on the model and it has been cut from steel.  The smaller gear is still aluminum because I need to fabricate it on the end of the governor itself.  I will make it again, but in steel, when I build the governor.



Having worked out potential problems with the bevel gears, I thought Iíd look into fabricating the sprag clutch.  I guess I could purchase one of these but I made the one on my first Otto Langen and it works well so Iím going to attempt to make this one also.

Here  is an image of the clutch internals.  You can see that it is comprised of an outer shell with a series of ramps cut into the inner surface.  Inside this shell is a round rotor, attached to the drive shaft.  There are cylindrical rollers placed on the ramps between the outer shell and the internal rotor.

When the central shaft is rotated clockwise the rollers are rotated to the thicker back of the ramps and the central shaft can rotate freely.  When the central shaft is rotated counter clockwise the rollers are rotated to the thinner front of the ramps where they jamb in the ramp.  This causes the outer shell to be carried around with the central shaft.


This is my drawing of the outer shell with the ramps.  This is one of many drawings Iíve made to assist me in the construction of the ramps.  With this drawing I can locate and drill the four outer mount holes as well as some ďstarterĒ holes for the individual ramps.



Finally, here is the setup on the mill.  Iíve started work on the outer ring blank and have drilled all the holes indicated in the above drawing.  Next Iíll start fabricating the ramps.

« Last Edit: September 12, 2019, 01:03:58 AM by Craig DeShong »
Craig

Online b.lindsey

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Re: Crossley Otto Langen
« Reply #19 on: September 12, 2019, 01:43:49 AM »
Making good headway on the design and fabrication both. Still following as closely as I can ...good stuff!!

Bill

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Re: Crossley Otto Langen
« Reply #20 on: September 12, 2019, 01:55:35 AM »
Following along here too!  I love the diagram of the clutch, very interesting. Are the rollers balls or cylinders?

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Re: Crossley Otto Langen
« Reply #21 on: September 12, 2019, 07:05:01 AM »
Craig, did you cut both those gears with the 45degree setting? I would have thought you need something more like 20/70 as anything other than 1:1 are cut at different angles for pinion and wheel.

Have a look at Simon's lane and Bodley  thread

http://www.modelenginemaker.com/index.php/topic,7093.msg205179.html#msg205179
« Last Edit: September 12, 2019, 07:08:56 AM by Jasonb »

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #22 on: September 12, 2019, 05:41:04 PM »
Bill and Chris; thanks for your comments. 

Jason, thanks for the input; getting helpful input is one of the reasons I post here.  According to a calculator I found, the angles on the gear cones should be 71.5 degrees and 18.5 degrees so you were pretty much spot on.  Though the gears I made seem to run well, I'm going to look into this.  Thanks.

The rollers are cylinders.  I'll make the clutch itself out of steel and the rollers out of brass as I did with my first Otto Langen.  This allows the rollers, which can be easily replaced, to take the wear as opposed to the machined surfaces.  Hardening the clutch would probably be a better solution but I haven't seen the necessity.

I'm appending a PDF of the clutch that you should be able manipulate.  I don't know if the board will allow this type of PDF for fear of transmitting a virus and if the board doesn't I can understand why.
« Last Edit: September 12, 2019, 07:20:04 PM by Craig DeShong »
Craig

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #23 on: September 16, 2019, 09:48:26 PM »
Moving forward with the design of this modelÖ

As I stated up thread, Iím keen to hash out some of the potential problems with this build; problems that might end up changing the design.  I wouldnít want to put a lot of effort into the actual build, only to find out that a re-make of a lot of what Iíd completed was required because  of a design change.  Iím going to go ahead and make the clutch and .. JasonÖ have a re-look at the bevel gears before the design progresses any further.  Once I get over these two potential hurdles Iím pretty sure the design will be ok.

Starting with the sprag clutch.  The internal design of the clutch is to have ramps that ďjambĒ rollers in place, forcing the entire mechanism to spin in one direction and allow the rollers to clear the ramps and allow the internal rotor to spin freely in the other.  Getting the ramps machined correctly is critical to the success of this clutch.

Below you see the layout for one of the ramps.  The given measurements come out of the design tool.  The ramp is, in reality, an arc of a circle with the center offset from the center of the clutch.  Each of the six ramps gets the same x,y offset with respect to its placement on the disk circle.  Here Iím showing just one of the layouts for clarity.



To machine the ramps Iím using my rotary milling head.  This allows me to mount the disk in my milling vice and use the x,y coordinates on the table to set the offset for the center of the arc, and then mill the arc using the rotary milling head.  One thing I didnít plan for was the need for a long reach end mill, since the depth of cut is 13/16th inch.  I ordered three and broke only one. ;D



Below is a better view of how the milling operation was performed. 



And a photo of the completed clutch shell with the six ramps finished.




With the outside of the clutch complete I started on the internal rotor.  This piece mounts inside the above part and is fixed to the main shaft with a key.  Here Iíve sized the piece, drilled and reamed the center hole, and machined a lip where a bearing will interface. 



Hereís a photo of the completed rotor with the keyway broached.


Next Iíll be looking at the sides of the clutch housing and the bearings.
« Last Edit: September 16, 2019, 10:31:34 PM by Craig DeShong »
Craig

Online crueby

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Re: Crossley Otto Langen
« Reply #24 on: September 16, 2019, 09:53:40 PM »
Great work on the clutch! 

Thats the first time I've seen a milling head like that, it must be an interesting mechanism inside it to drive the spindle at an offset. A rotary table/adjustable offset in the mill head, that would open up all sorts of operations. Is that a common accessory for larger mills?
Chris

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #25 on: September 16, 2019, 10:41:37 PM »
Chris, I don't believe these are that common.  Several companies made "attachments" for the Bridgeports and Bridgeport clones to extend their capabilities and Volstro was one of them that made this milling head for the Bridgeport and several other mills I believe.

I have a machinist friend who has one and some years ago showed me how it worked.  When I got my Bridgeport some time back, getting one of these milling heads was on the "to do" list. 

Today, of course, they are all obsoleted by CNC machining.  You can pick them up from used equipment dealers for a reasonable price if you are patient.  There were two for sale at Cabin Fever last January, priced at about the top of the price range.   
Craig

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #26 on: September 18, 2019, 08:45:02 PM »
Thanks for those of you following along.

Today I finished the work on the Sprag Clutch and I couldnít be more pleased.  The clutch functions well, freewheeling in the one direction and instantly and positively grabbing in the other.  There is also no tendency to ďstickĒ when the direction is reversed after engaging.

With this post Iím documenting the machining of the remaining component partsÖ Here is a photo of the sides of the clutch.  The inboard clutch side attaches to the drive gear, thus the four drilled and recessed holes in the one cover.  The other four holes present in both sides are for assembling the clutch body.



Since the outside of the clutch freewheels on the shaft the clutch needs bearings to support the clutch body (the part with the ramps) and center it over the rotor.  Here is one of the bearings.  The narrow diameter presses into the center hole in the cover while the larger end fits in the recessed side of the rotor.



This is the onboard bearing.  It is longer because the drive gear (the gear that meshes with the rack) rides on this bearing and is attached to the clutch body.  I havenít made the drive gear as of yet.



Now a photo of the clutch under assembly with the rotor and rollers installed within the clutch body.  Itís sitting on one of the covers and the other cover is sitting alongside, waiting to be attached.



Proof is in the pudding as they sayÖ I made a ďdummyĒ shaft, just to test the functioning of the clutch and clamped it in my vice, keyed the shaft to the internal rotor as will be done on the real assembly, and assembled the clutch; here is the result. 


Now to revisit the bevel gears and once I work them out I can think about completing the design and get into some serious building.
Craig

Online Brian Rupnow

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Re: Crossley Otto Langen
« Reply #27 on: September 18, 2019, 08:52:03 PM »
Craig--I've always known how those clutches work, but I never seen anyone make one before. Great stuff!!!---Brian

Online Craig DeShong

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Re: Crossley Otto Langen
« Reply #28 on: Today at 02:31:16 PM »
Brian: Thanks for your comment.  Thanks also to those stopping by to see my progress.

Here is a photo of the bevel gears on the full size Crossley Iím attempting to model.


As I stated previously and as Jason so kindly pointed out up thread; I needed to re-visit the design/construction of the bevel gears that will drive the fly-ball governor on this model. 

Jasonís comment prompted me to do a little research and the research lead me to this URL https://daycounter.com/Calculators/Bevel-Gear-Calculator.phtml which is an on-line bevel gear calculator  I found on the net.  If you input the diametric pitch and the relative number of teeth you wish the two gears to have the calculator supplies you with all the pertinent information you need to design/cut the appropriate gears.  Put in a DP of 32 and 10 teeth on the pinion and 30 on the gear and youíll get the numbers with which Iím working.

I had a few false starts that reduced the length of a bar of Ĺ diameter aluminum tubing Iím using to form the pinion gear by a few inches and added some heft to my scrap bin, but in the end I got things sorted out.

At the risk of being overly pedantic, Iím going to go through the steps to make one of these bevel gears.  No special equipment is needed (like Chuck Fellowís helical gear cutter I used on my previous project); just a few gear cutters and a dividing head.  Ivan Law fully describes the process in the book I mention up thread. 

Forming a bevel gear required three passes for each gear tooth. After completion of the 1st pass the gear blank looks like the photo below.


You should notice that each of the gear teeth form a wedge.  The next two passes will remove additional material so that the individual gear teeth are formed correctly.  This is done by rotating the dividing hear ľ of the travel normally done to advance to the next gear tooth position and then adjusting the height of the mill table so that the cutter enters the gear blank from the center of the gear, in the center of the previous cut, and shaves material off the bottom of the gear wedge, forming the top of a gear tooth.  In this photo Iím about to start pass two.



Here is another look from the other side of the same operation.  Itís hard to tell exactly whatís happening in these pictures (and hard to tell when milling the gears also).  Sound more than anything is an indicator.  The cutter enters to blank with relatively little sound and the sound of the cutter removing material intensifies as it cuts deeper into the wedge.



With the second pass complete, the bottom of all the gear teeth has been formed.  Now the gear blank is rotated backwards Ĺ the rotation you would require to advance to the adjacent gear tooth, the mill table is lowered so that the gear cutter again enters the gear blank from the center of the gear, in the center of the previous cut, and material is shaved off the top of the gear wedge, forming the completed gear tooth.  In this photo Iím about to start the 3rd and last pass.



Here is a photo of the complete gear



The pinion is formed using the same three pass technique.  Lastly I give you a short video of the two gears.  Both these gears were cut from aluminum as a ďtrial runĒ to make sure I have the correct design and process.  Now Iíll repeat the process using steel.
Craig