Quick Motor Shaft Question
 

Hello,

I've recently been wondering how you'd remove a motor which was epoxied to, say, an aluminium roller. For example, an RS550 to a simple, aluminium roller, held in via epoxy. Will the process damage the motor or shaft in any way?

It takes a while for new motors to reach Australia. ;)

Thanks in advance.

Re: Quick Motor Shaft Question
 

If you don't mind my asking, how on earth did it end up epoxied anyhow?

Re: Quick Motor Shaft Question
 

It depends on the glass transition temperature of the particular epoxy which was used.

If you can heat the epoxy above its glass transition temperature without exceeding the temperature which would damage the motor that would allow you to separate the parts.

Once separated, you could use xylene or acetone to soften and remove the epoxy. Use chemical gloves and adequate ventilation.

Re: Quick Motor Shaft Question
 

Well someone Who would think about this might want to look into acetone. *disclaimer* I'm suggesting looking into it not going ahead and doing it I have herd acetone works on epoxy but I would do a small test and look into it more befor going todo the real thing

Re: Quick Motor Shaft Question
 

I always use a lighter to heat the motor shaft up.

Re: Quick Motor Shaft Question
 

You're probably going to need more heat than a lighter will provide.

Something like a propane torch would probably work better. If you can heat the wheel/shaft up from the side opposite the motor and hit the motor with freeze spray or a continuous jet of compressed air then you should be able to keep the motor cool enough to avoid damage while you're getting the shaft off.

On the other hand, it sounds like you don't care about the motor that much. In which case flame on till you loosen up the epoxy enough to extract the motor. Just make sure to do it in a well ventilated area.

Re: Quick Motor Shaft Question
 

I think they DO care, because they don't want to damage the motor. :p

The best way is going to be by heat, but lots of it. Either a heat gun or torch (even better) might work.

Also, acetone apparently "loosens" the epoxy a little bit, but not very much.

Of course, the other way to do remove the shaft and epoxy is with a lathe!

Name a problem a lathe can't fix! :rolleyes:

Re: Quick Motor Shaft Question
 

Off hand, I'd say a lathe wouldn't be great for welding two pieces of plate together.



Bet you thought I'd say milling a slot in something, right? But I'm just nerdy enough to know that you can, in fact, mill with a lathe. And you could probably abuse it into acting as an arbor press and half a dozen other things. Welding seemed my safest bet.

Re: Quick Motor Shaft Question
 

Depending on the lathe, I think you could weld with one. Of course, that would be totally abusing it... And the weld wouldn't hold real well unless you ramped up the force a lathe can exert--and I mean REALLY ramped it up--but in the land of theory, it might be possible.

Now, arc welding, yeah, I can agree with you on. (Friction Stir welding is the type a lathe might possibly be capable of.)

Re: Quick Motor Shaft Question
 

Doughnut holes.

Re: Quick Motor Shaft Question
 

We removed a press fit shaft that was glued on with red loctite threadlocker (one of the uses is press fitting) using a propane torch, the motor raised our forklift all of 10,000 Lakes regional without issues.

Re: Quick Motor Shaft Question
 

First, the original problem: Heat softens all epoxy. Eventually.

Then, The Lathe: There is no problem a lathe cannot fix.

Re: Quick Motor Shaft Question
 

Just a word of caution: I've heard suggestions for the use of flame and acetone on this problem. Please don't use them together! Any flame in a room with open acetone is begging for a visit from the fire department.

Dr. Bob

Re: Quick Motor Shaft Question
 

I've attached a picture of what we've done. Oh and we'd like to save the motor and have it fully functional after we're done. :) The motor shaft is epoxied to the rod.

Re: Quick Motor Shaft Question
 

If you could cut the rod off to expose the shaft (if you're careful you'll only loose a millimeter +/- a bit)and heat the remaining rod section while cooling the motor with compressed air, the remaining shaft portion could be removed with a conventional gear/pinion puller (the kind that pulls the gear and pushes the shaft, if you push against the motor can you could crush a spacer [yes, I have done that before]).

Better yet, you could heat the shaft before cutting it. That could reduce the risk of motor damage.

Re: Quick Motor Shaft Question
 

Cut the rod off like Alan said. Then:

How much space is there between the motor and the rod? If there's enough space, get a piece of plate steel and mill a slot in it just slightly wider than the shaft diameter. Slide the exposed motor shaft into the slot in the plate so that the motor is on one side of the plate and the rod is on the other. Use a press to push the shaft out of the rod, with the plate providing the reaction force on the other end of the rod.

Re: Quick Motor Shaft Question
 

Like so?

Re: Quick Motor Shaft Question
 

Yes. Like that.

Now find a strong steel tube with ID just slightly larger than motor OD, and slip it over the motor so the slotted steel plate rests on it and is supported all the way around.

Re: Quick Motor Shaft Question
 

Would it be advisable to use a soldering iron to heat up the Araldite? I found an MSDS to it if it helps.

http://msds.duluxgroup.com/pdf/shess...0703514101.pdf

Re: Quick Motor Shaft Question
 

If you have room for that slotted steel plate you can probably just push the shaft out with a press.

Re: Quick Motor Shaft Question
 

I get the feeling that we'll end up pushing it out using a hammer a vice and some sort of smaller steel rod. We don't have access to a press.

Re: Quick Motor Shaft Question
 

Set that slotted steel plate on that steel tube I mentioned earlier. Find a very short hardened steel rod. Hold the hardened steel rod with a pair of needle-nose pliers and bang the motor shaft out. Wear your safety glasses.