MT Couplers

[John]

I've purchased every DODX flat car release to date .. I'm noticing that some of the cars constantly uncouple .. I've taken the couplers out of the pocket, reset the springs, etc . but it doesn't always fix the problem ..  thoughts?

 

[ChristianJDavis1]

Aside from things like uncoupling from mismatched heights/irregular track work and looking to see if the pins are all the way in, maybe check for flash on the coupler that would keep them from staying together? I've had similar problems on old Kadee couplers (before they were branded MT), but I never really looked into why they did it.

[ns737]

are these body mounted or truck mounted?

[randgust]

OK, here we go....again.....

You need to really see if those cars have the RDA angle on the couplers if you are having VERTICAL pull-aparts.     Before that was done, it was virtually impossible to not have pull-aparts on long trains, piggybacks included.

The permanent fix is to take a VERY sharp #11 Xacto blade and cut a very mild 'V" on the fingers of the knuckle so that the harder you pull the harder they center.  You have to imitate what MT did with the RDA knuckle:

https://www.nscale.net/forums/cache.php?img=http%3A%2F%2Fhome.earthlink.net%2F%7Ebhender730%2Fsitebuildercontent%2Fsitebuilderfiles%2Frda_mt.jpg

You have to do this to every coupler in a train to make it effective if the problem is pull-aparts (one coupler high, one coupler low).  There are a lot of things that can go wrong, but if you don't the the heads line up properly under a hard pull, there you go.

[peteski]

OK, here we go....again.....

 . . . the RDA angle . . .

I had to smile.
Just like an ATM machine, or a VIN number? 

Since these are newly released cars, I would expect that couplers to be the RDA type, but it is worth checking under magnification.  Also, if those are all identical cars, but only some of them seem to uncouple, then that would indicate that the problem is with some of the cars.  Interesting problem.

John, is it always the same cars that uncouple, correct?
What if your switch their locations within the train? Does the uncoupling problem follow the same cars?
Or is it a combination of 2 specific cars coupled together?
Also, how often is "always"?
How about the locations where they uncouple?  Same, or different every time?
How do they uncouple?  Vertical pull-aparts, or they just open up and uncouple (horizontally)?

[BCR 570]

I am experiencing this with a lot of MT couplers lately; even factory assembled ones.  The problem seems to be that they don't always stay closed.

Tim

[John]

I had to smile.
Just like an ATM machine, or a VIN number? 

Since these are newly released cars, I would expect that couplers to be the RDA type, but it is worth checking under magnification.  Also, if those are all identical cars, but only some of them seem to uncouple, then that would indicate that the problem is with some of the cars.  Interesting problem.

John, is it always the same cars that uncouple, correct?
What if your switch their locations within the train? Does the uncoupling problem follow the same cars?
Or is it a combination of 2 specific cars coupled together?
Also, how often is "always"?
How about the locations where they uncouple?  Same, or different every time?
How do they uncouple?  Vertical pull-aparts, or they just open up and uncouple (horizontally)?

1) These are current release DODX flats -- both the 68' and the longer cars ..
2) It's usually the same car or two
3) Always is -- always
4) Locations -- anywhere in the train .. coupled to different cars
5) They have all been checked with a guage -- and line up height wise -- the MT DODX flats are body mounted -- the coupler box is is molded on .. so its not that -- they just uncouple horizontally ..

It looks like the coupler doesn't close properly .. and if there is any "slinky", especially when the train slows, the knuckle is open to wide to keep them together ..

I'm going to take them apart again and put new springs in as well as new knuckles .. I think they are the same parts as the 1025s ..   It's just frustrating

I've seen the same thing on the log cars and eventually managed to fix those ..

[John]

I am experiencing this with a lot of MT couplers lately; even factory assembled ones.  The problem seems to be that they don't always stay closed.

Tim

Exactly what I'm seeing ..

[muktown128]

Calling @Shipsure ...

[jdcolombo]

If the coupler itself is freely moving from side to side (e.g., the mounting screw isn't over-tightened), then the next thing I'd try is a shot of dry graphite in the coupler.  MT sells it as their "Grease 'Em" lubricant, but you can get tubes of dry graphite powder from lots of sources (do a search on "dry graphite powder lubricant").

My experience has been like Tim's - I find a lot of recent couplers don't close up properly after being pushed open.  If the train bunches and the coupler faces push open, then don't close when the train stretches back out, you'll get an uncoupling.  Every time.  After I check them for free movement, I shoot some graphite in the coupler, work the faces back and forth a couple of times, and in most cases, the problem has been solved.  In a few cases, I've had to disassemble the coupler, rub graphite on the two halves, and then reassemble, and THAT has fixed the problem.

John C.

[John]

If the coupler itself is freely moving from side to side (e.g., the mounting screw isn't over-tightened), then the next thing I'd try is a shot of dry graphite in the coupler.  MT sells it as their "Grease 'Em" lubricant, but you can get tubes of dry graphite powder from lots of sources (do a search on "dry graphite powder lubricant").

My experience has been like Tim's - I find a lot of recent couplers don't close up properly after being pushed open.  If the train bunches and the coupler faces push open, then don't close when the train stretches back out, you'll get an uncoupling.  Every time.  After I check them for free movement, I shoot some graphite in the coupler, work the faces back and forth a couple of times, and in most cases, the problem has been solved.  In a few cases, I've had to disassemble the coupler, rub graphite on the two halves, and then reassemble, and THAT has fixed the problem.

John C.

John.. thanks .. I shot them with some labelle 134 PTFE .. in a couple of cases it did the trick .. I'll go ahead and take apart the stubborn ones next

[JanesCustomTrain]

I shot them with some labelle 134 PTFE ..

You're entering Dark Waters territory with this stuff...   

Jane

[Peavine]

Ive been having a lot of trouble with new MT releases also.  The body mount couplers seem to constantly uncouple. I bought a four pack of covered hoppers which cannot make one lap of my layout without uncoupling. And don’t get me started with the DODX sets. I have them all, and its very frustrating to do all the weathering and detail worh of installing the loads only to have them shriek, scream, and derail constantly because the wheels are contacting the body. I had to disassemble every one of mine and dremel out the bottoms to keep them from contacting. I can’t be the only one...

[peteski]

You're entering Dark Waters territory with this stuff...   

Jane

I usually use powdered graphite (not Teflon) following Micro Trains recommendations.

[John]

Ive been having a lot of trouble with new MT releases also.  The body mount couplers seem to constantly uncouple. I bought a four pack of covered hoppers which cannot make one lap of my layout without uncoupling. And don’t get me started with the DODX sets. I have them all, and its very frustrating to do all the weathering and detail worh of installing the loads only to have them shriek, scream, and derail constantly because the wheels are contacting the body. I had to disassemble every one of mine and dremel out the bottoms to keep them from contacting. I can’t be the only one...

1) I need to figure out the coupler issue -- this is frustrating as heck ..

2) Didn't MT change their wheel profile a while back -- could that be the cause of the body contacts -- if so, maybe replacing with the older lo-pro or metal wheels could cure the issue?