On the Great Planes puller set:

FWIW, I have it and love it. I do have some tips though. I also bought this puller https://www.amazon.com/gp/product/B00GDAJYSK

Walkera W010 Gear Pinion Puller Remover Tools Set For RC Motor Pinion Parts

The why is because both use the exact same thread on the pusher. This gives you a wider selection of matching pins for different shafts. I've also found that these pins fit into the MTH worm gears and are needed to give you the total pin length required to push them off. Put the silver pin inside the gear, use the other black pin on the Great Planes puller, you can press the gear right off.

For flywheels, I also got this puller since the gap between the motor and the flywheel prevents other types from working. I chucked up the screw section in a drill and used a Dremel and cutoff wheel to shape the pointed tip into a shaft as it needed to match the motor shaft size and actually go into the flywheel some.


Again, what I found best was buying the silver Walkera puller set, and using both sets, then you have the ultimate puller set. I saw earlier in the thread that others made custom pins for the Great Planes puller, and that's a good route too, just saying, I don't think folks might have known the 2 completely different brands were compatible, and the resulting combination set can do what the custom pin does, and more.


I grabbed the Walkera set, I'll see if the pins fit the Great Planes and allow the full push.

I want to get some longer screws for the Great Planes set, and I liked the idea of using some steel tubing to align them properly as well.

The Timko puller works for me with flywheels and wheels.

Jetguy posted:
 Put the silver pin inside the gear, use the other black pin on the Great Planes puller, you can press the gear right off.

I'm not getting what you're talking about here.

Sorry, don't have it in front of me at the moment to take a picture, so trying to do this via edits.

The silver Walkera pins are of a smaller shank diameter and then also have the smaller pin tip. It just so happens that that diameter happens to match the typical bore size of the MTH worm gear from the end. The MTH worm gears (at least every one I've touched PS1, PS2, PS3, steam or diesel) is a stepped bore system. The bore through the actual screw section is larger, and then the solid shank section that matches the motor shaft is stepped smaller. It just so happens the length of these pins is near perfect as is the diameters and step shaft size. So you insert the silver pin with the small end first into the end of the worm gear. The sizing is such that the bore keeps the pin straight so the smaller tip aligns and presses on the nose of the motor shaft deep inside that worm gear. Externally, your puller is pushing on a pin, that pushes the motor shaft out of the gear. This puts no pressure on the motor body or the armature (something you already know not to do). I've circled the pins I commonly use.

Then they insert, small end first into the larger bore end of the worm gear.  Again, what folks may not know is that is a stepped bore, not a straight bore. The step is where the threads end typically. So if you use a motor shaft sized pin, it can often kink or bend in the long wider bore section because it has room to bend sideways. If you have a stepped pin, it reduces the length of the small shank and reduces the chance of bending the pin.

Image result for mth can motor

What I'm getting at is one method is a custom machined extra long pin to press these long worm gears off. Extra long for some steamers. If you make that extra long pin the same diameter as the motor shaft, even in hardened steel, it might flex, bend or break over such a long length. You could step size it diameter wise, and that's an option. What I'm giving is a third option. There is a way, with no custom pins, just these 2 puller sets, to mix and match parts such that the silver pins can be dropped into the worm gear bore and act as short of a shuttle pin, a pin that floats inside there and transfers the pushing force. This allows the puller with standard pins to push on this shuttle and press the shaft right out of the worm gear. Those same pins come handy in dozens of other situations and the fact the silver threaded section also matches the black Great planes threads means you can adapt the parts of the 2 pullers for a lot of situations that a single set could not.


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I know the inside of the worm is stepped, nice to hear this pin will push them all the way off.  Putting them back on should be easier as I have the arbor press to do that job.

Yes, putting any pressure on the body of the motor is a sure way to kill it!  I have several examples that have been sent to me for repair to verify you shouldn't do that.

I have a K-4 that model that had diecast rot and no replacement parts available for it so I have been using it for parts. I left it at a shop that I do work for. I will be going there tomorrow and I will do my best to remember to pick it up. Please contact me VIA email in my profile.

I just received my puller from Great Plains the other day. I’ll be making y’all some pins when I get back from York.....it’ll be my pleasure....(at least until I burn up all the tool stock I have 😊) I know John wanted one and Ted, and maybe one more....y’all can shoot me an email as to who needs them bad....I’ll get the service guys like John first out....as they use these tools all the live long day.........Pat

The Water Level Route.......You Can Sleep

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