C&O 0-10-0 switcher

[mmagliaro]

I *think* you'll be okay grinding that front motor face back a little.  But you might want to do both: grind a little on the frame and grind some on the motor, until it can just drop in there.   Looking at how that shaft sits about where the idler gear is, what you really want is to move the motor BACK somewhat.  That black cover on the rear of the motor can come off, and then you'll see the wire solder points and such.  You could put a thin styrene disk back there in place of it, and that should let the motor move back a little.  And of course, you could completely cut away that rear frame plate, allowing the motor to go back as far as you want.

Have you tried running the motor on your workbench with some variable DC?  If you have never done this with a Maxon motor, you really should, just for the entertainment value.  It's pretty freaky to see a 12 volt motor start turning at something like 0.3 volts.

[peteski]

Yes, the brass front of the motor can be turned down quite a bit.  Here are few I turned  on my lathe. It will give you an idea by how much the motor can be shortened.

[mmagliaro]

Update on that sleeving I posted the link to:
Look on Amazon (or anywhere) for CynKen stainless capillary tube.
Among many other sizes, you will find it in:

OD 1.5mm  ID 1.0mm
OD 1.5mm  ID 0.9mm
OD 1.5mm  ID 0.8mm

It arrived today.  Since it is coming from China, expect a long shipping time (a few weeks).   As I had hoped, the sleeving fits
push-on tight on the Maxon 1.0mm shaft.  It's not so tight that it has to be pressed on with a gear puller/press, but it also isn't a "slip fit" either.  It goes on with finger pressure, but is nice and snug.  That is exactly what I would have hoped for.  When I experiment by sleeving a Maxon 1.0mm motor shaft with some of this stuff, and then push a Kato/Atlas standard worm over it, I'll start a new thread and post some pics.  But so far, I am very optimistic.

[peteski]

Thanks for that report Max. I also ordered bunch of those capillary tubes (haven't arrived yet), and it is good to know that they will work well for sleeving the motor shafts.

[Kentuckian]

Yes, Max, thanks for the link and the follow up report. I’m waiting on mine, too. I am working on the tender and boiler while waiting. Hopefully I will have something more to post soon.

[mmagliaro]

Just adding a cross-reference to a separate topic I created about sleeving these motors and pushing the worms on...
https://www.therailwire.net/forum/index.php?topic=48618.0

[Kentuckian]

Ok, I finally received all my Amazon stainless steel sleeve orders. This is the situation:



The worm shaft from the stock motor is 1.2mm in diameter. The new Maxon motor shaft is 1.5mm in diameter. My current idea is to use a dremel to cut off the stock motor shaft, that of course will have the worm already mounted. This avoids me trying to remove the worm from the shaft, an operation that historically has been an issue for me. @mmagliaro I ain’t! I have 2.0x1.2 mm sleeve that I can install to bring the worm shaft up to 2.0mm. I also have 2.0x1.5mm sleeve that I can use to bring the motor shaft up to 2.0mm. Then I can use my 3.0x2.0 sleeve to connect the two shafts.

The only problem is see is the length. I only have about 3mm or so in length to accomplish all this, so the two shaft sleeves will be pretty short.

I am certainly open to constructive comments and alternate suggestions. I also have an Atlas/Kato diesel worm that is mounted on a 1.5mm shaft. Using this would only require one piece to splice the motor and worm shafts together, the 2x1.5 mm sleeve. Does using the original worm matter much or not? The diesel worm is the upper one in the photo:

[Lemosteam]

Ok, I finally received all my Amazon stainless steel sleeve orders. This is the situation:



The worm shaft from the stock motor is 1.2mm in diameter. The new Maxon motor shaft is 1.5mm in diameter. My current idea is to use a dremel to cut off the stock motor shaft, that of course will have the worm already mounted. This avoids me trying to remove the worm from the shaft, an operation that historically has been an issue for me. @mmagliaro I ain’t! I have 2.0x1.2 mm sleeve that I can install to bring the worm shaft up to 2.0mm. I also have 2.0x1.5mm sleeve that I can use to bring the motor shaft up to 2.0mm. Then I can use my 3.0x2.0 sleeve to connect the two shafts.

The only problem is see is the length. I only have about 3mm or so in length to accomplish all this, so the two shaft sleeves will be pretty short.

I am certainly open to constructive comments and alternate suggestions. I also have an Atlas/Kato diesel worm that is mounted on a 1.5mm shaft. Using this would only require one piece to splice the motor and worm shafts together, the 2x1.5 mm sleeve. Does using the original worm matter much or not? The diesel worm is the upper one in the photo:

@Kentuckian If that is an OEM Minitrix worm gear, I have several already removed from motors that you can have, and if I don't I can press one off easily enough.  PM me.  I'd be happy to mail them to you.

This way you can just ream the hole to the shaft size you want.

John

[mmagliaro]

I'd really take John up on his offer if he has a worm for you to use that he has already pressed off a shaft.  I think using multiple pieces of sleeve to cobble it all together in so short a distance will be hard to keep true.

Also, I think the Trix worms are module 0.4.  Kato gears are mod 0.3 (except for a few exceptions like the GG1 and later era SD40-2, which use finer mod 0.2 gears).  And it doesn't look to me like the profile of the worm teeth is the same between the two.  They may look similar in that photo, but I don't think they are, and that would mean that the Kato worm won't mesh correctly with the gear in the Trix engine.  You might "get away with it", but everything would be so much better and safer using the original Trix worm.

[Kentuckian]

John, thank you for the generous offer. Max, thank you for the usual sage advice.

John, knowing you have my back gives me the confidence to try to remove the worm. I have a new to me technique to try. I hope to get to it today; I will let you know one way or the other. First I have to find a piece of aluminum.

Thanks again.

[mmagliaro]

If it helps...

I have had a lot of trouble getting the worms off Trix motors - both on the K4 and the 0-6-0 B6.  Some were so tight that they would cause the hardened pin to bend on a gear puller, and I could not get the gear to budge.  What ultimately always worked was to make a heavy plate with a V-shaped notch in it, clamp it in a vise, and hang the motor in the notch by the worm (with the motor or armature hanging down).  Then get a small piece of an old wire drill bit (just to use it as a hardened pin).  Pick one that is almost as big as the motor shaft.  Hold it in some pliers on the end of the shaft, and whack the motor shaft out from inside the worm with a hammer.   It seems a little barbaric, but it's really not.  The motor isn't exposed to any shock or damage, and sharp whack of the hammered pin will free that shaft and let it pop right out of the inside of the worm.

[Kentuckian]

Success! Only took two whacks with the hammer using Max’s method. But now onto the next issue. The sleeve for the motor shaft is 2.0x1.5 mm. The inner diameter of the worm looks pretty close to 2.0 mm to me. I don’t think there is enough meat on the worm to ream it out to 2.0 mm.

So I’m thinking ream the worm to 1.5 mm and mount the worm on a 1.5 mm shaft, then use the 2.0x1.5 mm tube to sleeve the two shafts together. The photo shows the 2.0 mm tube and stock worm.

[mmagliaro]

Great!

And definitely, don't try to bore out that worm bigger than 1.5mm.    Yes, I think 1.5mm, and then sleeve the two 1.5mm
shafts together as you suggest, is the way to go.

Question... that shaft on your Maxon motor looks AWFULLY short, and looks like it was chopped off.  Did it come that way when you bought it?  How much shaft do you have to work with on the motor?

How are you going to ream out the worm from 1.2mm to 1.5mm?  That's about .012".  I've done it by hand just with a few successively larger bits in a pin vise, using an actual reamer at the very end so you end up with a nice snug fit on the shaft. 

[Lemosteam]

I opened up the bore of the brass worm quickly, and by hand, using a Dremel 113 bit.  All of my lifelike motor conversions in my Minitrix locos were done this way.  Just enough clearance to wick the Loctite red in there.

[Kentuckian]

Thank you both, again! I have a box full of dremel bits but apparently not that one. I need to go to Lowe’s today anyway for a honey-do project. It will be a day or two before I can get back to this, anyway.