Steam Tractor 3/4" (Rudy K)

[Don1966]

I believe Jason is correct I hadn't noticed it. The brass should cut clean and at a high speed.

Don

[Kim]

Thanks Pete, Mal, Don & Jason!  I do appreciate the encouragement and the suggestions!

Jason, that's a very interesting idea.  It should be easy to test, but I'm not sure how to sharpen the cutter.  Its just tiny, and anything I do, I fear, will only make it worse!  I tried running a diamond stone over the cutting surfaces, but I just don't think I can make it better free-hand.  I'll have to figure out some way to jig something up to sharpen.

Kim

[Don1966]

Kim looking at the cutter in the picture, the cutting edge looks rounded over where it should be flat.

Don

[Kim]

Hi Don, thanks for the input.  I think you and Jason are right, and I’ve tried to address this, as  you’ll see below…

Also, it seems that the site was down for most of yesterday. I wrote this update but was unable to upload it till today.  Thanks to whoever got the site back up and running again!

-----
It’s been a few weeks since I’ve posted an update, mainly because I don’t have much progress to show.  I’ve run into several complications, most of them being self-inflicted.

I decided it was silly to go with the big gears first, so I moved to the smaller ones, and am currently aiming at the 32 tooth gear.

My first set back was this: I struggled with one of my gear cutter blanks.  It turned poorly – kept grabbing and tearing.  It just turned really bad.  This is W-1 tool steel, and I’ve never had any problem with it before. I don’t have a clue what was going on.  I tried annealing it and thought that would help, but it didn’t. I was just pushing through with it, but then, my button tool broke, like so:


With that, I scrapped that button, decided to make one with a 1/8” pin (as opposed to the 1/16”).  So I made a new tool, and a new button.  Heat treated it and here it is, ready to go:


That whole episode cost last weekend.  This weekend I used a new cutter blank with the new tool and it worked dramatically better.  I’m thinking that I just didn’t anneal the blank well, otherwise it should have worked fine.  And I don’t know why I needed to anneal it in the first place.  Can Tool steel work harden?

Anyway, I very carefully created my 32 tooth, 48 DP gear cutter.  I made this one with much more attention to the spacing than I did the others.  I was careful with them, but I was that much MORE careful this time around.  And I think it helped.

Another thing that probably helped was that I sharpened the cutting face to remove that somewhat rounded edge.  I did it using my HH Advanced Grinder Rest, like so:


Then I made a blank for the 32 tooth gear (0.708” dia) and gave it a spin.  No pictures, since it looks just like all the others.   But… as I was getting to the last few teeth, I started to realize that I was running out of space on the gear blank!  The teeth wouldn’t all fit.  And I found that I hadn’t tightened the collet holding the gear blank.    I clearly remember reading someone having this issue a week or two ago, and thinking to myself “I’ve done that before!  That’s why I check my collets CAREFULY every time before I start a cut.”    Guess I’m not as careful as I thought, and now I’ve re-learned that lesson!  (probably not for the last time).  Anyway, my 32 tooth gear came out at 31.5 teeth.  I went ahead and cut the last ½ tooth twice so that it was REALLY noticeable.  Because it’s not even a useful 31 tooth gear – it would likely have very uneven tooth spacing.

But at least the teeth are coming out with a better profile.  I’ll keep working on getting them even better!

OK, so still all the gears to go. Someday, I’ll make a keeper and start making forward progress.  Till then, I guess it’s just more practice gears!

Thanks,
Kim

[b.lindsey]

It's still progress Kim. Maybe frustrating at times but still progress. I am learning a lot from your posts too!!

Bill

[10KPete]

Paying attention to the detail on the cutter made a huge difference. It's very plain to see! That cutter is no bulldozing the gear material now.

You've got it on the run now!!

Pete

[Kim]

Thanks Bill and Pete!
I'm getting there!  But as I keep telling my wife, what's the fun if it works the first time?  That means I'm not really learning anything new, right?  (and I keep telling myself that too )
I'll whip these puppies into shape before too long! 
Kim

[10KPete]

Well Kim, don't bang your head against the wall too much
'cause you'll get a headache
and also go bald. 

Pete

[Don1966]

Kim don't beat yourself up buddy, it's all in the learning. Your making headway even though you have mishaps because your teaching yourself. The last gear looks a whole lot better just a slip of the collet. The buttons have to be annealed because they will snap just like the one you did, so anneal it well. The one thing I want to point out is that you are trying and that's a plus for you. You will not regret your efforts.

Don

[Kim]

Thanks Pete and Don,
I really do appreciate the encouragement

I'm really not feeling that beaten down about it.  As you said Don, I'm seeing a lot of improvement in my gears, and I'm confident I'll get usable gears.  I mean, look how far I've come?  Last year at this time I was learning to do rivets and having a time with my soldering.  Following that I did a bunch of sheet metal work, all new to me.  And now I'm doing gears!  I mean, how exciting is that?    All these new things were the motivation for me to take on this project in the first place (That, and the fact that it's so cool!)  And I'm not sorry I tackled it in the slightest.

Clearly, I'm not an expert at any of these areas. But I'm having fun, learning a lot, and getting better - thanks in large part to your help, and everyone's help on this wonderful forum.

Thank you!
Kim

[Dave Sohlstrom]

Kim

Are you a member of the Portland Model Engineers club. They meet in various locations on the second Sat of the month.

Dave

[joe d]

Kim

Things are looking good!

If you ever figure out a use for it, I've got a 79 & 1/2 tooth gear left over from my Minnie....

Joe

[Tennessee Whiskey]

Kim, I haven't said much, but,  I have been  ,  , and following along.  I've only cut one set of gears and one test gear,  which all seemed to work out well.  I attribute this to the dividing plates I added to my RT.  Are plates available for yours?  I applaud you for doing it by the "degree setting,  don't know if I could 

Cletus

[Kim]

Kim

Are you a member of the Portland Model Engineers club. They meet in various locations on the second Sat of the month.

Dave

Hi Dave,
Yes, I'm a member of PME, and even come to some of the meetings - though I haven't been in a while since its hard to find the time.  There's even a meeting a week from Saturday isn't there?  It's not too far from my house so I might try to show up.  Do you attend the meetings on a regular basis?

Though I like the idea of meeting with people face to face, with the way my world is right now, I find it difficult to set aside specific time for a meeting.  It takes time away from my family on a Saturday, which is one of the few days I get to see them.  But I still like to try

The forum tends to fit my topsy-turvy schedule more easily, since its here when I have time.

If you ever figure out a use for it, I've got a 79 & 1/2 tooth gear left over from my Minnie....

Joe,
We can put your 79.5 tooth gear with my 31.5 gear and we'd be set!  Something good would be bound to come out of that! 

I applaud you for doing it by the "degree setting,  don't know if I could 

Hi Cletus,
Thanks for looking in on me!  Actually, using the RT and dividing by degrees hasn't been a problem for me (yet... knock-on-wood).  It's been getting the gear cutter made well, made sharp, and centered on the blank, and a dozen other little niggly things.  I think I've tripped on them all, and found that indeed, what people tell you is important in making gears, is in fact, quite important!

Thanks,
Kim

[Kim]

At my last update, I'd just made a splendid 31.5 tooth gear.

This update, I will show you the creation of the 32 tooth version!

I'm trying to make each gear better.  So this time around - in addition to remembering to tighten the collet  I took some extra pains to make sure everything was lined up properly.

First, I re-checked my RT to make sure that it was going around in circles without any run-out (or atleast minimal run-out).

Second, I tried a different method to center the cutter.  Before, I was lining up the bottom of the cutter with the top of the gear blank, then dropping the cutter 1/2 the width of the cutter+gear blank.  This should work perfectly, but I feel that the teeth have been coming out slanted one way or the other, so I decided to try something else. This time I set the cutter to center height by lining up one of the teeth with a center that I'd put in the RT collet, like so:


And third, I made a rod, 3” long, uniform diameter (turned between centers on my later) and used this to more accurately adjust the position of the tail stock.  Before I was lining it up by eye.  This way, of course, was much better.  I was able to accurately position the tail stock, and not move it to put the mandrel with the gear blank in place.


OK, that’s all that I did different, and the next steps were the same.  But I took pictures of them anyway.  The blank set on the mandrel, all set for cutting:


And here we are, 32 carefully spaced cuts later:


And after a little clean up (I need to do a bit more I can see):


I’m quite pleased with this gear!  And it makes me feel that I’m going to have to re-do all the others, which I kind-of assumed I would anyway, but seeing this makes it quite clear, even to me!

But now I’m one down, and eight (or so) to go!

Thanks for your help and support,
Kim