Author Topic: Steam Tractor 3/4" (Rudy K)  (Read 242145 times)

Offline scc

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #510 on: January 09, 2017, 09:22:30 PM »
That's a lot of good work Kim,     Your persiverence certainly pays.  I'm very impressed.

Regards           Terry

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #511 on: January 09, 2017, 11:32:51 PM »
I'm just starting to make the geas for my Rudy engine. I'm having trouble finding the sizes for the gears such as od and thickness. So far I have the big gears cut square getting ready to  to make round and cut teeth. I am using 1/8 thickness 1/4 hole od 25/8. It looks like all the other gears are 1/4 thick is that true. Thanks. Ed PS made my own gear cutter.

Hi Ed,
I could not find any info on the width's of the gears in Rudy's plans.  I made my best guess and went with it, which looks to be the same direction that you're heading.  I made the bull gears (120 tooth) 1/8" thick, and all the rest 1/4" thick.  As for the diameter, I used Don's spreadsheet (which he pointed you to in his reply).

Now that I've made the gears, I'm working on fitting them up in place.  It looks like a couple of them might have been only 5/32" wide, instead of 1/4", but I'm not certain of that.  As I'll talk about in one of my  next posts, I'm making some modifications to the Counter Shaft, and the Idler Shaft to match the widths of the gears I made.  But I don't think the width is really that critical as long as you make them all line up! :)

But I'm with you Ed, I just couldn't find anywhere that he discussed the widths of the gears.

Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #512 on: January 09, 2017, 11:33:12 PM »
That's a lot of good work Kim,     Your persiverence certainly pays.  I'm very impressed.

Regards           Terry

Thanks Terry!
Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #513 on: January 20, 2017, 05:32:09 AM »
I just want to say thank you to Ade for getting the forum back up and running so quickly!
It's a minor miracle that you had a back up as recent as you did!  Jan 10 is only 9 days ago. Yes, the loss is sad, but it will be only a blip in a few weeks.

I will be reposting my progress between the 10th and today.  I happen to have all my updates saved locally.  None of the replies of course, but at least there will be some continuity in the major plot line for the future. 

No need to repost comments.  We'll get to that when I have something new to update!

Thanks,
Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #514 on: January 20, 2017, 05:32:35 AM »
After completing the gears, I now need to get them mounted in the power train.  To do that, I have to complete that step that Ed just brought up – how to attach the gears to the shafts.

What Rudy does, is to make hubs with a set screw for most of the gears and join them to the gear with solder.  His assumption being that most people will purchase gears, so will have to add these hubs later.  But since I was making them, I could have been smart and machined them WITH hubs!  I actually got smart and started doing that for the later gears.  But the earlier ones I made were hub free.  So, I'll do some of them Rudy's way.

But before I went and made those hubs, I decided I needed to determine the actual the spacing of the gear train.  The collars are also used as spacers, and since it’s not clear how wide Rudy’s gears are, knowing the width of the hubs he specifies is of limited value.  So, I spent some time and sketched out a cross section of the gear train for the tractor.

Armed with this, I was then able to proceed to create the spacers and gear hubs of the right size to make it all (hopefully) work.

The first thing I did was to extended the 1/8” sections of the counter shaft. I extended them to 1/4", the width of my spur gears.  I wonder if Rudy’s were 5/32" wide?  This is what he used. I don’t know.  But this should work for me.



Here it is, 1/4" long.  I didn’t change the overall length of the countershaft.  Just the length of the 1/8” portions on each end.


Next I made a small pile of 1/2" x 1/16” thick spacers (washers).  This will help align all the gears according to my drawing.  I’m using a few more of these than Rudy shows.  Not sure why, but that is what makes sense to me.


Next, I turned the Idler Shaft from 3/8” Hex 303 Stainless rod.  I shortened the shaft section of this to 3/8” long (from Rudy’s 7/16”).  This leaves room for two 1/16” spacers, and the 1/4" wide Idler Gear.
Here I’ve turned it down to the basic shape – 1/4” for #8-32 threads, and 3/8” (plus a few thou) for the 1/4" shaft.


Oh yeah!  I almost forgot – I wanted to introduce you to my new Christmas Present!  The Diamond Tangential Tool Holder.  I really like it.  I’ve played around with it a bit and it works quite well.



Using my tailstock die holder, I threaded the 8-32 section.  Then reversed the die for the 2nd run to get a little closer to the edge.


Then cut off the Idler shaft.


Flip it around in a 1/4" collet, face off the end evenly, and round the edge a bit with a file.


And here’s the idler shaft, complete:


After this, I made a few of the hubs and spacers. These were all quite simple turning exercises, plus adding a set screw to a couple of them.

And here are all the miscellaneous parts I completed for the power train:


Now, to hook them all up!
Kim
« Last Edit: July 08, 2017, 06:39:40 PM by Kim »

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #515 on: January 20, 2017, 05:33:36 AM »
But wait!  I just THOUGHT I was done with the gears.  I forgot one step!  I wanted to cut spokes in the bull gear!  This certainly isn’t necessary, but I wanted to do it.  And it looked more prototypical to me too (plus, that’s how Rudy’s gears are!).    I’ve seen lots of people do this on flywheels and it looked fun. I figured I should be able to do it no prob.

So, as is often the case, I started by sketching it out to determine how to do this using my RT.  There is a lot of symmetry here and it turns out there are only a few numbers needed, as you see in the short table at the bottom.  And even with that, two of the coordinates actually make the  same hole, so I can just use one of them.  Of course, the other 3 have to be repeated 6 times - once every 60 degrees.


Then, I put the RT on the mill, and got it all centered up.  I don’t really have enough headroom to use the coaxial indicator, but I made a special super-short tip, and was just barely able to squeeze it in.


With that done, I started to think about how to hold the gears in place.  That was harder than it should have been.  I tried lots of things. In the end, I came up with this:  I made a center for my RT to keep the gears centered, and I mounted an aluminum plate on the RT that I could drill & tap some holes in to use for hold-downs.

To make the center, I turned a 1/2" steel rod (12L14) down to 3/8” to make some 3/8”-16 threads.  This is how you attach things to the center hole of the Sherline RT.


Then, I cut the threads.


Next, I made a section 7/16” in diameter.  This is the center hole size for the Sherline RT.  And next, I cut a section of it to 1/4" diameter.  This is the center hole size of the gears.


After cutting it off, here’s the center (siting on the RT).


And now, the 3/8” threads are screwed in place.  You can see that a 1/2" length of the 7/16” diameter is still sticking up above the RT.  This will help center the aluminum plate I will use for the hold downs.


Apparently, I forgot to take a picture of my 1/2" aluminum plate, but you can imagine it with a 7/16” hole in the center, and 4 Socket Head Cap screws holding it to the top of the RT.  Then I drilled & tapped some holes to use for the hold downs, and mounted a sample gear in place.  This is one of my messed up attempts at the 120 tooth gear.   I decided to do a practice one, just to make sure my math worked out right, and to give me practice turning the handles in the correct direction.


First step: Drill the holes at the bottom center of the cut out – every 60 degrees (this will have 6 spokes – did I say that yet?)


Then holes for the outer left corner:


Finally, holes for the outer right corner:


After that, I used a 7/32” end mill to connect the top corners using several passes.  Then, I did a single clean-up pass with a 1/4" end mill.  Using two different sized end mills let me do the initial cut, and the clean-up pass, using the exact same X-Y and RT coordinates, and simplified the operations significantly.  And of course, repeated this 6 times too.


Next, I cut the right side using the same method as above.


And then the final side.


And it’s done!  That only took several days – mainly to figure out and build my retention mechanism, followed by several hours of crank turning.  But it worked!


Now, I have to do the REAL gears!
Kim
« Last Edit: July 08, 2017, 06:40:04 PM by Kim »

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #516 on: January 20, 2017, 05:34:15 AM »
And now, for the final installment of the seemly never ending saga of Kim’s Gears…

For the final moment of truth!  (or hours of truth really :) ) Cutting the spokes in the REAL gears!

That whole process took long enough that I decided I didn’t want to do it two more times. So I stacked up the two bull gears and went to work:


After drilling all the holes for the corners, I used a Sharpie to mark in the area I wanted to remove.  This helped me visualize where I wanted this hunk of swiss cheese to go, and hopefully helped improve the prospects of removing the correct sections!


I don’t want to bore you with all the same pictures again, but I did include a few highlights.  So here’s the top curved sections removed.


And then all done!


And finally, I’ll leave you with a family shot of the 9 gears I’ve made for the steam tractor:


Thanks for following along on my heroic journey!
Kim
« Last Edit: July 08, 2017, 06:40:30 PM by Kim »

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #517 on: January 20, 2017, 05:34:45 AM »
My plan was to get the whole gear train put together today!  I’m pretty close, just have to do a few more things before I’m ready.

First, I need to add the set screw to the 66-tooth gear.  So, here goes:


After that, I decided it was time to solder the gears up.  Unfortunately, it was still 28 F outside today, but I’d waited all I could.  I braved the cold, opened the door and did my soldering.

I made a little jig to keep the 1/4" center aligned with the 1/8” center – the post is aluminum.  I don’t think this would work if I were sliver soldering, but just soft solder, it should be fine.


Here’s one of the hubs.  I’ve cleaned it, put a little flux there, and a few pieces of solder.  The solder I had was way too big, so I took a piece, pounded it thin, and used some side-cutters to nibble off little pieces.  Then I placed them strategically around the area to be soldered.


Then, I put one of the 16-tooth spur gears on top – cleaned and prepped with a dab of flux.


I originally tried to use a little butane torch I had, but it just couldn’t get the whole setup hot enough to even do this low temp solder.  So I switched to my Oxy-Acetylene torch.  I used the smallest tip I had (000), and kept the heat moving, away from the solder, and it worked smashingly well.


Then I did the same to the 66-tooth gear and the other 16-tooth, like so (I put a screw in the set screw hole to help keep the threads clear):


And finally, I soldered a hub on the 32-tooth gear.  Both of these had a 1/4" holes, so I changed the setup a bit.


Here is the output of all my soldering (burr, it was cold!)


With that complete, I waited a bit, and then closed the door. My shop started to warm up right away!  8)

Last, I needed to mount the bull gears to the rear wheels.  This is done using three 4-40 screws.  And as usual, the most difficult part was figuring out how to hold the whole thing in place while you machine.  This is what I came up with to drill these holes.  Here I’m using the edge finder to line up the RT using the spokes.


Then I spotted and drilled three holes, appropriately sized for tapping 4-40 threads.  I went back around and made a clearance hole through the bull gear.


Finally, I tapped the wheel hub.


And here are the two completed rear wheel assemblies.


Unfortunately, I didn’t have enough time to get it all mounted today. So, that will be an adventure for next time out in the shop!

Thanks for taking a look!
Kim
« Last Edit: July 08, 2017, 06:40:52 PM by Kim »

Offline Jo

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #518 on: January 20, 2017, 08:41:56 AM »
 8) That looks good Kim

Jo
Enjoyment is more important than achievement.

Offline Steamer5

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #519 on: January 20, 2017, 09:00:46 AM »
Hi Kim,
 Dam you've got this gear thing beat hands down!
At this rate I might have to see if I can get another crop of  :popcorn: in!


Cheers Kerrin
Get excited and make something!

Offline vcutajar

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #520 on: January 20, 2017, 12:04:28 PM »
Thanks Kim for reposting.  It will surely be helpful to anybody following your footsteps.

Vince

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #521 on: January 21, 2017, 05:59:03 AM »
Thanks Jo, Kerrin, and Vince,

Thank you for taking a look, and for the comments!
Kim

PS And thank you to all the people who commented before too, but who's comments were a victim of the host crash.  ::)

Offline b.lindsey

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #522 on: January 21, 2017, 01:57:07 PM »
Rudy would be proud Kim. The gears really are beautiful too.

Bill

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #523 on: January 21, 2017, 06:45:09 PM »
Thanks Bill  :)

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #524 on: January 22, 2017, 05:11:45 AM »
[We are back to real time now.]

My goal for the day; to complete the power train for the tractor.  I’ve got all the work done to get there, I just have to put the pieces in place.

But it wasn’t very long before I hit my first snag. The head on the bolts holding the Horn Plates in place were too tall and interfered with the gears. If you look at the top of the picture, you can see that the gear has hit the bolt head but it still has about 1/16” to go.


My solution was to cut the bolt heads thinner.  I was sort of planning on doing this anyway, based on Jason’s comment WAY earlier in my thread when we were talking about the Horn Plate bolts.  But now it was time.  So I put them in the lathe and took the heads down, then rounded them a bit with a file.


After completing that on all the bolt heads, and reassembling everything, here’s how it looks.  Plenty of clearance now!


I had to fit the Idler Gear Mounting block in place too, since I hadn’t done that yet.  I wanted to wait to fit that in place after I had the gears and could make sure everything fit right.  So, I carefully marked the horn plate, drilled and mounted the Idler Block. Unfortunately, the Idler gear didn’t mesh well with its neighbors so I spent some time adjusting things till the did.  Unfortunately, I completely missed taking any pictures of this lengthy interlude.

Once I had the idler gear meshing well with the rest of the gear train, it was time to mount the rear wheels. And then I hit another problem.  When I put the spacer next to the rear wheel, it hit the heads of the SCHS used to attach the gears to the hubs.  Bummer :(


The resolution for this was to go back to the lathe and take a nibble off the spacers. This allowed the spacers fit down between the heads of the screws, like so:


With that done, the rear wheels were mounted, the set screws were tightened, and low and behold, it works!  The gears go-round and the wheels turn!  I couldn’t be happier!

Here are a few close-ups of the newly installed gear train.






And now, the family shot showing all progress to date.


Next up will be the steering!
Thanks for checking in,
Kim
« Last Edit: July 08, 2017, 06:48:27 PM by Kim »

 

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