Are All Scale Speed Motors Interchangeable?

[rrjim1]

I received 9 motors yesterday, only one ran out of the box. I tried Contact Cleaner and used a Dremel to spin the armature, didn't work. Yes, the motors I received all have armatures!   I then used a small piece of wire to push on the motor brushes while turning the motor with my Dremel.   That did the trick and now all 9 motors run.   

[MK]

Sounds like the brushes were stuck in their channels and needed some loosening up.

[rrjim1]

Sounds like the brushes were stuck in their channels and needed some loosening up.

No the brushes weren't stuck I tried just pushing on the brush and it didn't help.  IMO the commutator, brushes or both were tarnished as I had to put a little pressure on the brush for a few seconds while turning the armature with a Dremel.

[Drgwspup]

Hi guys, I've been following this thread and before it entered the dead horse zone I ordered 20 motors. (FYI the seller accepted my offer price of $1.25/each) I want to re-motor a number of revised F7 Katos. I'm excited because my EBay motors arrive today!

I have a question about removing the flywheels from a Kato or Atlas motor.  Several pages ago someone posted a pix of their hand made tools.  For those of us without that skill set, what would be a commercially available tool to accomplish the flywheel swap?

Any and all suggestion greatly appreciated!

Thanks,

Mark

[metalworkertom]

 I've been happy with this one.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F173129416520

[Drgwspup]

Thank you!!

[mmagliaro]

I got 4 today.  Two ran beautifully, starting at only 2.5v and drawing only 52 ma at 12v (no load).
One wouldn't run at all, and I had to pry out a brush holder, clean the armature with a brushful of alchol down in the hole, and then reassemble.  Then it ran great like the others.  The spring and brush were not misshapen or stuck from what I can see, so while I admit I doubted it, I am inclined to think that there is some sort of coating on the armature.

The 4th has a cracked magnet.   The motor runs poorly and ticks along as the armature raps against the raised bit right down the middle of the magnet where the crack is.  I pulled it all apart, removed the armature, cleaned and sanded off all the old glue, and put the magnets in with Walthers Goo (I have fixed open frame motors with dislodged magnets like this before... Goo does a good job).  We'll see how it goes after the Goo hardens.

It's a good deal, but... for a normal customer who just needs a working motor, I essentially got 2 out of 4 that didn't work.  That's why these things are under 2 bucks each.

They all have the tell-tale green goop blobs in certain armature cavities.  Judging by how quiet vibration-free they run, it looks like these have balanced armatures.   Really good thing.  I don't think they are new.  There is too much minor score marking and black stuff on the commutator surface.  Maybe these are factory rejects?  Motors pulled from returned engines?   It's really hard to say.

[peteski]

They all have the tell-tale green goop blobs in certain armature cavities.  Judging by how quiet vibration-free they run, it looks like these have balanced armatures.   Really good thing.  I don't think they are new.  There is too much minor score marking and black stuff on the commutator surface.  Maybe these are factory rejects?  Motors pulled from returned engines?   It's really hard to say.

It could be that these are production motors which were dumped inot a large min after the N scale factory in China closed.  In that type of storage, they would have been in a "scratch and dent" condition.  Then a surplus dealer bought it all and is selling them on eBay.  Like you said, they appear to have armatures balanced, but have signs of improper storage.  I doubt they ere pulls from returned engines.  I don't think that (in today's disposable society) anybody would have bothered to pull the flywheels off.  Rejects? Possibly, but for what reason?

The bottom line is that even if only half of the motors are good, the price is still right.

[mmagliaro]

I agree that for the price, it's worth buying a bunch, doing your own "QC", tossing out any rejects, and keeping the good ones.
So... the one with the glued-back-together magnet is running.  It doesn't quite have the edge that the other 3 have, but runs pretty darn good.   It draws more like 70 ma instead of in the 50's, at 12v, and it won't reliably start up below 3v like the others - more like 4.   However, it is running better than it did at first, now that I've run it for a few minutes in both directions, so it may yet smooth out.  After all, having had the whole case apart, the brushes and bearings all have to find their "happy place".  And it's running far better than it did out of the package.  I'm still deciding whether to relegate it to "spare parts".

[mmagliaro]

An update... I sent a message to the eBay seller, telling him about the problems with 2 of the 4 motors, and he is refunding the cost of those two.  I must say, in all my experiences buying from China on eBay, the customer service has been excellent.  The products are usually fine, and if they aren't, there is no problem getting a refund.

[Drgwspup]

I've been happy with this one.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F173129416520

Hi metalworkertom.  I ordered the flywheel puller you suggested.  Unfortunately the flange(?) is too thick to fit between the flywheel and the motor.  Any other suggestions?  Grind down the flange?

TIA

Mark

[Steveruger45]

FYI, I use the same puller to get the flywheels off my n scale motors.  The flange fits if you turn it so the groove faces the motor.

[atsf_arizona]

What do all of you use, to press a different flywheel onto the motor shaft? 

[Steveruger45]

I heat the flywheels up in a cup of boiling water for a few minutes and (wearing gloves) push them on by hand.

[Drgwspup]

Hey Steve,

Thanks for the reply. on an old thread. I can get the puller to work on some of my atlas and kato motors but the ones I want to remove are from the revised F unit mechanism. Those motors have a round plastic mounting ring between the motor and flywheel resulting in most of the gap being filled.  Any other suggestions?

TIA

Mark