I have an IMRC FTA that has given me nothing but trouble for years - it just doesn't want to go, and when it finally does go, it doesn't want to keep going. Well, I finally took the thing apart and thoroughly cleaned and adjusted all of the metal wipers and contact strips and whatnot. And... no change. So, now I'm looking at the motor. And although I can't recall ever having a problem with a modern motor before, this one is looking kind of funky to me. What's up with the white crap on the magnets and the green shmootz between the magnets? Is that a problem? Is it fixable? Thanks, -Mark
From a brief Google search, seems to be moisture related. I am not sure if I have ever seen something like this before but perhaps only on engines that have been stored.
Spookshow, It might just be the angle the photo was taken at but it looks like the bottom magnet has moved away from the case. Is the magnet touching the armature? Is there an air gap between the magnet and the armature? If the magnet is touching it would be just like putting the brakes on. Hope that these observations might help with fixing the problem. Gary
Mark, this is a guess, but it looks like a reaction has occurred between the winding insulation and a corrosive chemical. I suspect a liquid may have been dropped onto the armature during assembly or a previous owner's maintenance procedure creating the "stuff" visible on the armature. That stuff may be dragging on a magnet pole which would cause the armature to slow while running, or prevent it from turning all together. You might try cleaning that area with 91% alcohol and a toothbrush, then a Q-Tip saturated with alcohol. However, if that doesn't solve it, you'll have to replace the motor. Good Luck.
My bad, I think I've been barking up the wrong tree here. I tried running the motor with current applied directly to the contacts and it ran fine. So, I put everything back together (except for the trucks) and tried running it with current applied directly to the chassis contacts. Also ran fine. So apparently I still have some cleaning left to do on those trucks. FWIW, I dug a Life-Like motor out of my junk box (thinking I might need to swap it into my FT) and it had the exact same green crud between the magnets. How odd... Thanks, -Mark
"green shmootz between the magnets" Not tring to be smart or anything but the armature is between the magnets. The (I think it's green) between the two armature poles is how they balance the arm, do not remove it. All the new Atlas motors I have purchased have white paint on one pole, not sure why the manufacture does this. It sure won't hurt to clean it up, just be careful of the magnet wires you can break them very easy. I would remove the brushes, check the springs, brushes and make sure the brushes move freely in there holders.
Nevermind, it was just the trucks. Cleaned 'em really really thoroughly this time and all is well. That's what I get for trying to play with trains so early in the AM Thanks, -Mark
Cool, I learned something new (several things actually). I always thought those things were magnets. -Mark
My two cents...Do not break the winding wire. It will not run. I did that on a Kato and replaced the motor okay. It sure was strange, though. With the winding wire broken (and impossible to locate it) all lights and apparently getting power...it just wouldn't move.
Mark,as was said,The "schmootz" between the comm segments is to balance the armature..The white paint is a mark they index in the balancing machine so they know where to put the schmootz when they balance it.They run it at high speed,and put a strobe light on it.The strobe shows where to put the schmootz in relation to the painted segments.In some cases,the paint is used to fine tune the balance on really high RPM[RC car..] motors...On some high RPM motors,all the segments would be epoxied so the wire can't fly off,and the comm is drilled/painted to balance it..
The factory heavily overgreased the first two or three runs of these. I had a B&O set that did the same thing. I hardwired the A and B together and that solved the stalling problem. I then complained about having to do that on one forum (I forget which one). An Official of IM posted immediately and advised me to send them to Longmont where the problem would be rectified. IM rectified the problem in a reasonable amount of time, but never did tell me what it was. Later I acquired an Old and Weary set that did the same thing. At the risk of voiding the warranty, I opened them up. I noticed that there was too much grease on the worm gears and in the trucks. A complete disassembly, thorough cleaning of all parts, careful re-assembly and a VERY light lubrication addressed the problem. I posted my experiences on a different forum. There, a now-former Official of IM posted that they had recently become aware of the problem and that he was scheduled to leave shortly on a trip to China. He stated that the responsible Managers of the factory there would receive a thorough blessing out. The Managers must have received their thorough and sound reprimands, as the problem has not appeared in IM F-3s and F-7s.
Mark, I'm very happy you didn't listen to my half-baked brain-f**t pulled from where the Sun doesn't shine. I never knew our N-Scale motors were so well cared for during manufacture. I mean, every one dynamically balanced at high RPM before it ever leaves the factory....WOW, I'm Impressed. For those as gray as me, can you imagine a Pittman DC60 or DC71 motor being dynamically balanced before being put into a Varney, Bowser, or Mantua kit 60 years ago?
Dynamically balanced,no,but I bet they were at least mechanically balanced.No big deal to put an armature on top of two razor blades,look for the heavy spot,and then use something like a Dremel Cutting disc or drill bit to take weight out of the heavy side..I used to check the balance on all my RC racing motor arms,and I would balance the arms I wound for my pullers.WE even used to balance the tires on our road cars by putting straight pins in the foam through the sides..
