Motor bushing removal

[RichieRich]

I have some beat up machine wound modifieds with bushings. They cleaned up nice and I've trued the comms and added new brushes. I was thinking of removing the bushings and installing some bearings. They really seem jammed in there. Does anyone have any tips for bushing removal and bearing installation?

[Coelacanth]

I've had pretty good luck removing sticky bearings by inserting a tapered round needle file from the opposite side until it catches the bearing, and giving it a firm tap (on a table or with a small hammer/side of a pair of pliers). Assuming the bushing isn't totally seized, there's only one way for it to go, and that's the direction the needle file is pushing it. Hope this helps!

[Lonestar]

For the head, it's all easy to push out and push back in, as the plastic (assuming you have plastic heads and not metal ones on your mills) is soft enough to allow you to do this without any special tools. Just don't use a screwdriver to push them out and back in as this will damage the material.

For the cage bearing, you can still push them out with pretty much anything, but you run a high risk of damaging them if you don't use a bearing extractor. For pushing them back in, you cannot do it properly without a bearing extractor... I mean, in both cases you CAN take stuff out and press it back in, but the stress on the bushing/bearing if you aren't using an extractor is going to damage it especially when pushing it back in, even if it doesn't necesarilly show to the naked eye. Most typically the bearing will start drilling at speed and you will loose top-end performance, or it will be seating slightly askew and will then rob some efficiency.

Here's what an extractor looks like

http://demonpowerproducts.co.uk/product_info.php?products_id=5011

Paul

[RichieRich]

Will that extractor work with brushed motors?

[jwscab]

just use whatever you have around to push the bearings out, screw driver, old wing tube, nail, etc, then push in the new ones by the outer race, not the inner one. clean up the bores really well in the endbell and can, and add just a smidge of lube on the outer race to it doesn't gall(on the can or metal endbells). Usually it's good enough to use something like a wooden dowel that is bigger in diameter than the OD of the bearing to press the new one back in, that will focus the pressure on the outer race.

[Lonestar]

Will that extractor work with brushed motors?

apologies - I actually linked a brushless one... the brushed one is different.

yes you can still press a bearing in the cage "by hand" with pretty much anything, but you'll only get it 99% there... the 1% you missed will cost you 10% in efficiency

Paul

[dldiaz]

Does anyone still sell a bearing puller for brushed motors?
I would like to do the same upgrade on several bushing (brushed) motors.

[igbandy]

I am sure some people will frown on what I am about to say, but hey ho.

To reinstall the bearing into the can I use an old armature with a bronze bushing installed on the pinion end. Then I put the ball race onto the armature and use a 4oz hammer to tap it home. Using the bronze bushing helps take the load onto the outer race instead of the inner race taking all of the load.

[jwscab]

that is an excellent method.

[RichieRich]

Fantastic advice. In fact, this worked so well, I ordered a few of those brand new machine wound Reedy motors from Associated on ebay. They have bushings but I tapped those out and installed bearings. Hey, a new mod motor!!

[REMJ666]

Nice tips...