Preview of upcoming MTL True-Scale Coupler system

[jereising]

Do you need them to be centered?  Since they don't have any swing, light cars, and especially those with a large distance between bolster and coupler pocket, will have a tendency to tip over.  I think you'd have to trim off the "centering whiskers" and probably also weld the two halves together.   See Jason's mod for the best way to do it and keep the click-to-couple functionality.

I'm surprised that the initial test batch didn't identify coupler swing as an issue.  I would be all over these with the back end spring and smaller box of a Z scale coupler, just with this head and no uncoupling pin.  I know they were trying to eliminate the slinky, but the eliminated the truck swing as well.  The slinky can be eliminated with two tabs.  But go back to the metal coil spring to allow more swing and a coupling force reduction.

Coupler to bolster would appear to be the issue here.

Centering really isn't an issue once the cars are coupled - it's only important when switching.

I REALLY like the coupler.  But if it is to be adapted beyond the testing stage there will need to be some different options.

As an update I am now working on my articulated autorack train with promising results.  Again, the cars had already been converted to body mount, and the process is going well.  First test was yesterday evening and had no issue with tilting.  But as was pointed out, coupler to bolster distance is less with these cars.

[Lemosteam]

Have you tried loosening the screw and allowing the coupler box to swivel on the screw?  here is what I think is happening due to the long overhang from the bolster to the coupler:

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The length of the overhang decreases the amount of force necessary to derail the truck at either bolster because of the greater offset that the coupler hase relative to the track centerline.  The shorter the overhang, the closer the coupler gets to the centerline of the track.

The overhang also creates a greater angle that the coupler must have relative to the centerline of the car.  If the coupler is restricted from swinging, the joint becomes locked forcing one or both cars off the rails.

[Tom L]

Letting the coupler box move works well. I put these on my MT heavyweights, which have a pin (instead of a screw) holding the coupler box and some molded "ridges" on either side of the mounting pad on to hold the box from moving side to side. I sanded down those ridges so the box can swing and I can run them around 11" curves with no problems other than the appearance.

Tom L

[jereising]

Yep, that's what's happening.

And I crapped out on the articulated rack train also.  The Atlas cars were fine, but the Athearn didn't play well with them.   The Athearn wheels, oddly enough, are much closer to the couplers.  They'd both work with others of their kind but not with the other.

I would live in fear of the screw falling out....

C'mon, M-T, give us some love here...

[AKNscale]

I had to have all of the coupler boxes pivot on my rolling stock to get them to work well without derailing my cars too. They function beautifully now because of it. However, on my B30 i had to put the long shank version on there and cut off the plastic "springs" so that the coupler can move freely. Eventually I want to see if I can create my own version of a centering spring for it, similar to the whisker setup on Kadees.

[jereising]

Interim report:

Since I was gonna have to touch all the cars I'd previously converted anyway, I decided to give the swivel a try.  I set up 10 cars so the couplers would swivel.  It worked well!  Made a full run of the layout with essentially no issues.  The worst part - and the best test - is coming out of staging with most of the train still on 2% and then going around two sharp curves.  If there's gonna be a problem, THAT'S where it's gonna be.  There were no problems.

I think I'm going to do the rest of the train in this manner.

I don't LIKE the swiveling couplers - a centering mechanism is definitely needed - but their advantages outweigh their disadvantages.

The main disadvantage is coupling.  It's nearly impossible trying to do it normally, and I find the best way to do it is vertical placement.  But this train is a runner.  It doesn't get switched.  Sooo...

[nkalanaga]

Maybe a very fine wire from the back of the box to the bolster for a centering spring?  if there's room, it would allow the entire box to swivel, but still be returned to center when uncoupled.  Fasten the wire at one end, and leave it loose in its hole at the other.  I've seen the same idea used to center pilot trucks on steam loco models.

[jereising]

Nobody ever said I wasn't stubborn...

I have the articulated rack train running successfully.  Took a lot of experimentation and trial runs and tweaking, but I was successful.

I did indeed use the swiveling coupler idea.  And I did the entire train with the short shank coupler with better results. 

The long shanks appear to have an issue with the spring where it meets the pivot hole, there is a weak spot there that will become a problem after coupling a few times.  The coupler no longer closes fully, and will then cause a break-apart and not readily couple.  The short shanks do not have this problem.

This is a pretty long train - if anyone is interested I'll give a car count - consisting of Athearn Auto Maxes and Atlas articulated racks.

Coupler height is absolutely critical if break-aparts are to be avoided.

I put a bit of Tacky glue in the screw hole to keep the screw from loosening.  I'd tighten the screw completely, then loosen it maybe a quarter turn, not much, just enough to allow a fairly easy swivel but not sloppy.  And I found that by setting the couplers this way, conventional coupling was possible.

So never say never!

[Ken Ford]

Jim, did you add a draft gear centering spring?

[jereising]

Ken, I felt that would be over complicating it. 

The couplers pretty much stay in correct position unless moved - that's what I meant by you don't want them too loose.

Again, remember this train will not be switched.

But the couplers don't flop around, you can even couple them in the normal manner.

[nkalanaga]

Most prototype couplers don;t have any centering device either.  They stay where you put them, and often have to be manually adjusted for coupling on curves.

[Ken Ford]

Right, and I actually prefer couplers that don't use centering springs (most of what I do is in P:48 with Protocraft couplers) - but I can't see where pivoting draft gear would be practical for non unit train use without some kind of draft gear centering mechanism.

[ednadolski]

I use the Protocraft couplers for P:48 and I just had to snug them up a bit in the box to keep them from flopping loosely when lifting the pin.  I find that I have to manually line them particularly on a sharp reverse curve such as on a #6 turnout into a spur, where the overhang can vary between cars.   Centering springs would actually be counterproductive in that situation anyways.

Ed

[ednadolski]

I have the articulated rack train running successfully.  Took a lot of experimentation and trial runs and tweaking, but I was successful.
<...snip...>
This is a pretty long train - if anyone is interested I'll give a car count - consisting of Athearn Auto Maxes and Atlas articulated racks.

@jereising, would love to know the car count, also #locos, curve radii, & gradient..... not to mention, pics and/or vids if you have any.

Ed

[jereising]

@jereising, would love to know the car count, also #locos, curve radii, & gradient..... not to mention, pics and/or vids if you have any.

Ed

Have a guest at the moment; I'll try to get something up ASAP...