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Discussion Starter #1
I've caught wind of a few reports of Canon motor failures causing RCMC motor drive section failures.
I recently over the last year or so have several engines using these motors and wanted to start a discussion on possible protection, understanding the modes of failure, and alternative retrofit motors such as Pittman motors.
Examples are putting in series with the motor fuses, breakers, or other protection like PTCs.

As part of this, my first candidate was my new Lionel EM-1 2031090 which I decided to retrofit a nice ball bearing Pitmann I picked up on the bay for $20 each and just cut off the encoder casting. I'll do a separate topic on that mod as I want to just give the background and really discuss the Canon in this topic. So as such, I then had a slightly used Canon I could take apart and inspect to try and wrap my head around the reported failures and better understand the motor and it's construction to determine the how and why of the failure.

So, here's the pictures of an opened Canon. Honestly, I'm no finding a lot that I'm finding bad, but maybe I just don't know or the failure mode is not obvious? I had to use a Dremel cutoff to notch the crimped can housing sections to bend them allowing the plastic end bell to pull straight out. I carefully wrapped the motor before doing this and even sealed the end bell to prevent metal shavings from contaminating.

So here is the armature at first look. There is a brass washer before the commutator as an oil slinger to prevent the brushes and commutator from lube oil from over oiling that rear bushing.
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Here is a side view better showing the arrangement. Also notice the nice surface finish on the commutator.
Sorry, I now realize the picture was not as clear as I had hoped.
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The end bell showing the stamped brush arms with inserted non replaceable brushes. Maybe this is what wears prematurely and fails? Also notice the foam attached to the brush arm springs to dampen them. I could also see say given even amperage and voltage abuse, the spring tension in the arms annealing and thus losing spring tension.
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I went ahead and pulled the armature completely. Notice the epoxied windings to prevent throwout and also the small colored epoxy balancing dots.
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Here is a shot of the commutator end inserted in the end bell with the brushes so you can also see that general arrangement. Again, sorry for the out of focus photo, I didn't see it on the phone until you post it here.
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Canon motors are popular with European locomotives and are also used for replacements. I've not heard of any premature failures of the smaller models. In fact, these are some of the best motors available.
 

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Discussion Starter #3
Basically my questions are:
If you've seen a failure, any notes on how it happened? Pulling a long train, running for a long time, or just a random failure?
If possible to check a bad known failed motor, did it short to frame ground? Or, was it just a low resistance short between motor leads?

Recommended mitigation?
PTC recommendations or values?
One lead or both leads (hence the short to frame ground question)

Potential sources for Pittman replacements, specific models, etc.
Example, 12V VS 15V Pitmann choices.

One gotcha I already encountered, the shaft and general mounting of the Canon has been a longer motor shaft than say a given Lionel Pittman and it matters because the stackup of the motor mounting bracket, the plastic flywheel protector, and the encoder spaces the flywheel and it's setscrews right at the end of the shaft. I found that the Pittman shaft on 2 different motors was just slightly shorter than the Cannon and just enough the flywheel could not be mounted because the setscrews missed or were so close to the end it would fail or just wobble off. In other words, Lionel designed the system around the Canon and as such, retrofits are not just as easy as I would have hoped.
 

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Discussion Starter #4
Canon motors are popular with European locomotives and are also used for replacements. I've not heard of any premature failures of the smaller models. In fact, these are some of the best motors available.
Given I've now seen the guts of one, I agree, IMO it follows good construction details- epoxied skew wound armature, diamond trued commutator, epoxy balanced (VS drilling the laminations causing eddy current heating), decent brushes, dampener foam details, oil slinger design on commutator end, decent bushings, solid can, basically sealed. Granted, it's a true non-user serviceable motor meaning you probably won't be replacing the brushes.

Just hoping others can fill in on the bad experiences and maybe it's the rare of rare problems if any.
I'm not saying everyone should run out and void the warranty and replace them, just trying to put a place and discussion on the failures and give those who know a good discussion on protection of the RCMC.
I've got several thousand dollars in about 7 or so of these now, and I intend to run them a fair amount over the next couple of years. It might just be putting PTCs in series, if so, what current value or specific part?
 

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Discussion Starter #5
Given I've now seen the guts of one, I agree, IMO it follows good construction details- epoxied skew wound armature, diamond trued commutator, epoxy balanced (VS drilling the laminations causing eddy current heating), decent brushes, dampener foam details, oil slinger design on commutator end, decent bushings, solid can, basically sealed. Granted, it's a true non-user serviceable motor meaning you probably won't be replacing the brushes.

Just hoping others can fill in on the bad experiences and maybe it's the rare of rare problems if any.
I'm not saying everyone should run out and void the warranty and replace them, just trying to put a place and discussion on the failures and give those who know a good discussion on protection of the RCMC.
I've got several thousand dollars in about 7 or so of these now, and I intend to run them a fair amount over the next couple of years. It might just be putting PTCs in series, if so, what current value or specific part?
Specifically, asking over here because I saw where @gunrunnerjohn mentioned Canon failures elsewhere.
I'm not trying to bash Lionel or Canon, just have a technical information sharing. Hence why I even took one of mine apart just to take pictures and share what I found.

I'm a firm believer in an ounce of prevention VS having to replace a $120 RCMC.
 

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John, aka GRJ has seen Canon failures. He can best fill you in. I only had one Canon motored engine, a Vision Niagara, and replaced it with a 12v 9433 motor from the same source as those ball bearing Pittmans. He was selling the motor I used before he started selling the ones with the encoder. Between myself and aother who has done many other Pittman swaps you can use any 12 or 15v 9433 or 9434 Pittman. Its not that critical.

Pete
 

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Canon motors are popular with European locomotives and are also used for replacements. I've not heard of any premature failures of the smaller models. In fact, these are some of the best motors available.
Keep them in Europe please, you're welcome to them there!

I have seen maybe 40-50 Legacy steam locomotives come through for repair, and three of them had failed Canon motors. Two of the motors where a dead short and fried the RCMC beyond repair. The 3rd motor appeared also to be shorted, but I was able to replace the driver FET's on that RCMC and return it to service, obviously with a new motor.

I'm sorry I never took the time to cut one of the motors open to see what happened, but I'm sure I'll get the chance at some point in the not too distant future! FWIW, I'm not the only one that has experienced these failures. Say what you will about that motor, IMO they're junk!
 

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I guess smaller motors are their specialty.
 

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Discussion Starter #9
I have seen maybe 40-50 Legacy steam locomotives come through for repair, and three of them had failed Canon motors. Two of the motors where a dead short and fried the RCMC beyond repair. The 3rd motor appeared also to be shorted, but I was able to replace the driver FET's on that RCMC and return it to service, obviously with a new motor.
Thanks for the input and appreciate the first hand experience. I'm curious, did you add PTCs on the replacements or just went with better motor swaps?
 

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Ii believe Harmonyards on OGR said he caught a Canon just before it took out the RCMC. In this case it was the brush holders that were about to break up. As long as you can get 20 dollar Pittmans, no reason not to swap them out. Easier and not that much more expensive than splicing in PTC.

Pete
 

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Thanks for the input and appreciate the first hand experience. I'm curious, did you add PTCs on the replacements or just went with better motor swaps?
They go out with what Lionel supplies as replacement parts. I actually suggested a Pittman swap to two of the folks, but they opted for the stock motors. Not my money, so that's what they got. Before any of mine get a lot of runtime, I'm thinking of adding a PTC, cheap insurance.

Pete is being a bit glib with the "easier than the PTC", that's not quite true. ;)
 

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I could see that and that makes perfect sense.
View attachment 557630
That's where the Canon motors end up failing. The brushes break off and short. With a better brush holder/brush plate design they would be fine for the most part.

I recently picked up a brand new 2019 edition Lionel ATSF 3751 class Northern. The first thing I did was swap the Canon out for a 9433 Pittman. It was an easy swap. I just enlarged the screw holes on the motor mount, used some screws that fit the Pittman (3/16 I think) and everything bolted back together.

20210312_223202.jpg
 

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Here's a picture of the brush plate from the Canon that failed in Harmonyards ESE Hudson. The retainer for the brush broke and the brush could flop around. That's probably what kills the Canons that fail. I'd be curious to know if Lionel buys the cheapest version of the motor. It's possible that a more expensive version of the Canon motor uses a better brush plate design.
Image.jpeg
 

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Hello fellas, ...I don’t get on here as often as I should,....I’ll fix that,...I had Lou share the pics of the Cannon I had fail,..each brush holder has 2 plastic “ears“ that keep the brush arm in alignment through it’s slot......I heard an audible clicking sound coming from the locomotive while running, I did indeed stop it in the nick of time, The locomotive began jerking violently and the lights were flickering, obviously heading to a short. If one of the ears breaks, the brush arm can wander around as now there’s nothing to keep it in alignment when there’s tension on it. The brush had obviously walked off the commutator. As John had mentioned, he’s already seen failures. As a side note, I’ve already removed the Cannon from Lionel’s latest Legacy J3a Hudson and swapped it out with a Pittman ,.....although it did not fail, i replaced it with a Pittman as mentioned above by my good friends Pete & Lou. I did observe a lot of shaft end play in the freshly harvested Cannon. I had mentioned to Lou that my Legacy J3‘s Cannon had a boat load of end play so I diid measure it for S&G’s and found it to have .009......might not seem like a lot, but going from forward to reverse every time, moves the shaft back and forth adding to the end play,......I’d have to say .009 end play would be discard point for me,.....when I set up Pittmans, I strive .002-.003 ......there should be only the tiniest bit of end play, I like to strive for almost zero, but not have a loaded bearing,....hope all this info is helpful....

Pat
 

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jetguy, we’ve been using those Pittman CPR motors for some time now, ....we have been really impressed with the performance numbers on a host of Lionel & MTH locomotives,....I’ve developed a really nice way to machine off the encoder housing, thus making the rear cap nice and round,.....we really like the generous ball bearing ends, and near bulletproof brush housing,...

Pat
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Discussion Starter #18 (Edited)
jetguy, we’ve been using those Pittman CPR motors for some time now, ....we have been really impressed with the performance numbers on a host of Lionel & MTH locomotives,....I’ve developed a really nice way to machine off the encoder housing, thus making the rear cap nice and round,.....we really like the generous ball bearing ends, and near bulletproof brush housing,...

Pat View attachment 557684 View attachment 557684 View attachment 557685 View attachment 557684 View attachment 557685
The one problem I'm having is the Canon motor has a longer shaft, so when I go to install the Pittman, by the time you have the motor mount, the plastic flywheel guard and the encoder in place, the flywheel even jammed as tight into the encoder as possible cannot tighten the set screws as they are either right on the edge or push the flywheel off the shaft.
The encoder PCB needs insulation as on the backside are some through hole vias and the plastic flywheel guard is pretty thin already.

So what's the magic fix you are getting to make it work?
Omit the plastic guard and replace with a thinner insulating method between the encoder PCB and the metal motor "L" bracket?
Thin the motor bracket?
Mill or lath cut a tiny bit off the face of the motor?
I don't see any room to mod the flywheel, the setscrew hole path already is into the groove of the plastic optical encoder.
The plastic encoder is so fragile, I see no good way of making it slightly less tall?
Maybe that Lionel Fastrack "expander" paste could work on stretching the motor shaft?
Anyone have a motor shaft stretching tool?
 

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I haven’t run into that problem. Both of the swaps I’ve done on the Legacy engines have required the smaller 9433 motors,.....but I do know what you mean,....worse case scenario, drill new set screw holes and tap,....you’ll need two, as the opposing set screws help to set up the alignment and reduce the run out,.....I’m gauging this on how thick the flywheel is on my Legacy J3, I don’t know about the EM1, ....is it thick enough to parallel the set screw holes?

Pat
 

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Discussion Starter #20 (Edited)
I haven’t run into that problem. Both of the swaps I’ve done on the Legacy engines have required the smaller 9433 motors,.....but I do know what you mean,....worse case scenario, drill new set screw holes and tap,....you’ll need two, as the opposing set screws help to set up the alignment and reduce the run out,.....I’m gauging this on how thick the flywheel is on my Legacy J3, I don’t know about the EM1, ....is it thick enough to parallel the set screw holes?

Pat
No, the holes are already into the very groove the encoder ring presses into. In other words, there is plenty of meat there to drill 2 holes further back-however, no way to tighten. You could drill an angled hole and tap, but that gets tricky and seems problematic. Sorry, it's late and I'm trying to grab any pictures I can find to show the situation and failing.
Here, you can see the setscrew holes, just imagine the groove from the backside that encoder ring sets in, the holes literally already partially intersect the groove or slot the encoder presses into. This barely allows the hex key so you can tighten in situ.
398889Dscn8561.jpg

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The problem is the thickness or height of the encoder plastic part. It's so fragile, I don't see a good way to make it thinner. That height is what limits the setscrew location spacing.
The ring is taller than absolutely needed, but without breaking any of the tiny arms you cannot easily shave it down to a lower height.
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