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New Member
My train's always seem to come un-coupled while in motion. Very much a pain...What would the most logical course of action be to correct this problem? I am using accumate couplers on these, HO scale. Any suggestions??

Many thanks!


Master Mechanic
First off, I would check the track. I will tell you that more than likely your track is the problem and until any and all bumps, kinks and bad joints are repaired or removed, the problem will continue. Biggest problem I've seen has always been the joints on curves, they should be soldered and filed smoothe.Once the track is checked, and the problems fixed, the uncoupling problem should get a lot better.

After you do this, and if the problem continues, just come back and we'll discuss this further.
Cjcrescent said:
First off, I would check the track.
I agree. Most uncoupling problems are due to vertical defects (bumps and humps) in the track. Combine that with couplers that aren't all the same height on the cars and there will be major uncoupling issues.


Diesel Detail Freak
WOHO! I get to push Sergent couplers again!

Track work, coupler heights, coupler tightening i.e. the screw on the cap being too tight or to loose causing droop... All common issues someone has run across.

Now for the product push (no I do NOT make anything off of this!). Sergent Eng. makes the most prototypical HO scale coupler, It works almost exactly like the real thing. They close snug enough to twart some derailments and most uncouplings. The stay closed, no annoying spring to loose, or plactic tap to break. And they LOOK REAL!

Now for the downsides (somewhat):
-cost, @ $9 for 5 assembled, takes time to convert (just as converting to all Kadee #58's or such would cost).
-coupler box size issues!!! Some manufacturer's coupler boxes are actually TOO THIN and can cause snugness on the coupler (just buy the assembly fixture and a few jewlers files to remidy this)
-Two "options" for mounting holes, the EC87A-125 for "standard sized holes" and the EC87A-135 for oversized (you can also buy tapered reemers att he same time for adjusting the hole size)
-need to buy NEW uncouplers (Sergent again has one, and it works AWSOME)
-WAY more manual then "normal" couplers but yet more prototypical
-lack of a centering device slows you sometimes, but can aid in corner coupling!

Oh there's the new ones that come with the scale sized coupler box now too...


Mile11, check the track as suggested. Next check coupler heights.
Then check the couplers are secure vertically [no wobbling].
After that check weights.
If you have a light flatcar say, just after the loco and then a heavier car or cars after it, that can also cause a derailment . The real railroads know this and so they put lighter or empty loads at the back of the trains.

I hope that helps :)


Diesel Detail Freak
bogp40 said:
It's too bad the Sergent couplers weren't compatible w/ Kadee.
Bob K.
Not a problem, just eliminate all Kadee's! :eek: Or as I'm going to do, make "idler cars" so people can run their own engines, or freight cars during operating sessions of my layout.

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