Atlas Trainmaster problem

[carmelmodelrr]

I have one of the first Trainmasters produced by Atlas.  It's been a wonderful engine until the last few days when it began derailing with some frequency.  I finally determined that the contact strips were the problem and after many bends and attempts to correct the problem, I bought new contact strips from Atlas.  That has minimized or perhaps corrected the derailing, but now the engine growls--loudly.  Except to loosen the two sides of the body so I could remove the trucks I have not had the body apart. 

Any ideas as to what suddenly went wrong?

Thank you.

carmelmodelrr

[tehachapifan]

If a truck contact slips behind, or in front of, a contact strip, yeah, that can cause derailments for sure. I'm assuming that's what you were initially trying to address. As far as new growling noises, hard to say what's causing that. I have heard of modelers attempting to address growling on certain models (not sure if this was one of them) by adding more downward bend to the contact strips, so as to add some more lift of the frame off the trucks. I think the idea here was that the worm was meshing too deep into the top truck gear and resulting in vibration/growling. Not sure if doing this solves anything or not as it seems like it would be really hard to get the contact strips to do any actual (and even) lifting. Another possibility is if a plastic pin on the trucks, which the frame rides on, broke off and is no longer holding the frame at the proper height over the trucks on one or both sides. Not sure if these models have that plastic pin or not.

[peteski]

Like Russ mentioned, growling is usually something in the worm/worm-gear area (either too shallow or too deep engagement), but I guess anything that is hitting other gears in the trucks could cause that kind of a noise.  If the loco was disassembled, it is probably not reassembled 100% properly.

What I find puzzling is how after many years of service those contact strips just suddenly got deformed all by themselves (without anything drastic happening to the model).  Those strips are well hidden, and all the do is rub against the truck contacts.  Not much force anywhere to get them bent.

[tehachapifan]

Also, make sure you've re-installed the trucks in the correct orientation. With many N scale models this shouldn't matter, but I'm not sure about the TM.

[Steveruger45]

Check the trucks, they have a nub each side which rides on the frame recess.  Sometimes those nubs or one of them break off or get damaged.  If this is so that could also cause the derailments and cause miss alignment of the contact strips.  As such the issue with the contact strips you had/have may not be the cause but a symptom.

[tehachapifan]

Rats! Wish I though of that one!

[Steveruger45]

Rats! Wish I though of that one!

Oops, i see you already did.      That will teach me to read all the posts. 

[tehachapifan]

No worries!