Looking for suggestions on how to remove a stubborn flywheel.

[jbrock27]

I recently purchased a 2nd hand motor that came from a '90s "blue box" model.  It has 2 brass flywheels and I was able to remove one, but not the other.  I suspect, but cannot confirm, that it has been glued to the motor shaft.  I saw a post from back in 2009 that provided a method of removing a flywheel, but there was no mention in that thread of glue being involved.  Because of its 2nd hand nature, I also cannot confirm what type (if any) glue was used.  I know there are pullers out there to purchase, but I believe this is a one time issue, since I have been able to remove both flywheels in order to disassemble and clean the motor on these types of motors I have previously purchased.

Thank you in advance for the time and assistance.

[bapguy]

If it is glued on try putting the motor in a container and leave it in the freezer for a few hours. This might loosen the glue enought o pull of the fly wheel.  Joe

[WoundedBear]

Freezing it will just shrink the brass flywheel and make it even tighter on the shaft. You need a proper little press to do it without damage. You could rig something up to support the flywheel, then use a pin punch to tap the shaft out.

What do I know though? I'm just a dragster mechanic

Sid

[jbrock27]

Good idea Joe; using the properties of contraction.
I did that once to remove a bearing race from a small trailer wheel.
Thank you for the suggestion.

[jbrock27]

Thanks Sid.

Now that begs the question Sid of: do I have something around that is that small to use as a punch?

[bapguy]

I should have been a little more specific. Freezing the part might cause the glue to break down. Remove the motor and let it warm up to room temperature before trying to remove the fly wheel. Joe.

[jbrock27]

Thanks again Joe.

Now if I had all the impressive tools my friend and Dragster Mechanic Extraordinaire, Sid, has at his disposal, I likely would have no need to seek suggestions on this 

[utdave]

  heat the flywheel  cool the shaft    take a burnt out motor cut shaft on one end  sand down shaft some and use as a punch .      i havent done any dc motors yet . but i do HVAC for a living and those stubborn pullys ometimes needs this concept to get them loose and off.        DAve

[jbrock27]

Thank you Dave.
I thought of that as well, but was concerned that heat would simply be transferred and potentially destroy other things, like the delrin plastic motor cradle and commentator of the motor or maybe even the windings.

I did try the "freeze" technique but was not able to twist the flywheel off the motor shaft.  I have not given a full effort to trying to "punch" the flywheel off the motor shaft.

[Doneldon]

jb-

Remove your motor from the loco before trying to pull the flywheel so you can get at things more easily. See if you can support the flywheel on two sides -- the open jaws of a vise are a good choice if you have one -- and then punch the shaft out of the FW with a nail set or other small, hard tool piece. Wear safety glasses as you do this as it's possible to send a chip of the tool or your hammer flying. That happens only rarely but you don't want to e the rare case where a piece chips off and hits you in the eye.

The other advantage of removing the motor, et.al., from the frame is that you won't have to worry about the effects of the heat on nearby plastic parts. Try the hot 'n' cold method again if you don't have a vise and cannot rig some similar support surface. Also, you may be able to rig a wheel puller from hardware pieces like stout mending plates or corner braces. Such a contraption can look pretty weird but nevertheless be effective.

Good luck with your project. I know such things can be frustrating at times.
                                                                                                                   -- D

[jbrock27]

Thanks Doc.
From the get go, I have had the motor out by itself.  The part I am concerned about heat being transferred to, is one half of the delrin plastic motor cradle.  It is the half that is on the commutator side of the motor.  It can not come off until the flywheel is off.
Good suggestion on the goggles.  It is always smart to wear them on such projects and when using a Dremel tool as well. 

[JNXT 7707]

jdbrock - you may have figured this out already, but thought I'd post since I've been working on a similar project, that requires removal of the flywheels from a Blue Box motor.
MicroMark sells a handy little tool for this that I ordered but have not had a chance to actually try out yet - although I did use it to remove some plastic u-joints from a shaft.
Hear is a link: http://www.micromark.com/wheel-and-gear-remover,9767.html

[jbrock27]

Thank you JNXT I appreciate your help.  Yes, I did find that previously.  Certainly looks like a nice tool,  Not sure though, that there is enough room for me to place the end opposite the pin, in between the flywheel and delrin plastic motor cradle. 
In the end I cleaned the commutator anyway, which was my reason for trying to remove the flywheel in the first place (I don't really have any other reason to remove the flywheel-it's in good shape).  I was able to clean the commutator  w/o having to take the flywheel off.  It cleaned up just fine and the motor runs well.

Can I ask, what are you taking your flywheel off for?