Best Of Notes on body-mount couplers (work-in-progress)

[Scottl]

+1 

[PJPickard]

Will these be for sale?
I need some!  I'm working on a caboose that if it comes OK I might offer for sale and I really need a solution like this.
I have started to design my own but why reinvent the wheel?  I'd only need the standard length one.

Paul

[DKS]

Well if DKS produced his coupler in these pockets (royalties to Ed and Gary included of course) Then we'd have one of those rare Win-Win situations . . .

Believe me, it's on the radar. Maybe not for release #1, but...

[jagged ben]

Okay, so remind me...

Will these only work with the FT couplers?  (And how do you get those again?)

Will it work with MT couplers (N or Z scale?)

Just weighing various issues here, including money...

[GaryHinshaw]

Hmm, lots of good questions here...  I'll try to answer them as best I can:

* FT's are compatible with all 3 N scale couplers: MT, Accumate, McHenry.   This post shows an example of an FT mating with an MT;  sadly they don't couple automatically, because of size differences in the knuckles, but they will stay coupled if you couple them by hand (by lifting one car).  They do a little better coupling automatically with Accumates and McHenry's.   Compatibility is one reason I am trying to stick with the MT height standard.

* It would be fantastic if the Proto-Mate shank were compatible with this pocket, but the highest priority for David should be a good design from first principles.  In the long run, my hunch is that Proto-Mates will be the way to go, but I don't have any real insights there.

* The only reliable way to obtain FT couplers is to buy the full Talgo truck, which is expensive (see for example Zscale Monster's store).  Last year, William Dean Wright, the FT developer, made "naked" (wheele-less) trucks available at a discount, but they were still expensive (maybe $3.50 a pair IIRC?) and that may or may not be an option going forward.  Now that we have a viable pocket, all we really need is the coupler itself, without the FT pocket (which is only made as part of the truck).  Perhaps we should explore purchasing the coupler alone?

* The pockets are specifically sized for the FT couplers and they will not work, as is, with the 3 main N scale couplers.  The design could easily be resized to accommodate either an Accumate or a McHenry (interchangeably), but I have no personal interest in doing so.  With the styrene post option, I can also imagine how this design could be adapted to accommodate an MT, but I shudder at the thought of trying to assemble them with the MT centering spring, and I think MT already offers plenty of pocket options.

* The intention is certainly to make these available to anyone who might want them, but we have not worked out the details of how.  My thinking was that we would start with a "group order" from PPD and go from there, but I haven't discussed this with Ed, or anyone else, lately.  Please stay tuned on that front.

Cheers,
Gary

[jagged ben]

My point of view, FWIW...

My interest in this would mainly be for better looking extended cushion couplers.   However, I'm dealing with a club environment where I would like to maintain complete interoperability, but can't control what couplers are going to be on other guys' equipment.    We also have track conditions and grades that make height tolerances a big deal.

Thus being limited to FTs is a bit of a deal breaker, regardless of cost.   I have no love for N scale MTs, but for now I'm afraid to go a different route.

MT really doesn't make any kind of part that's good for modeling extended cushion couplers.  So it would be great to have a product like this that would allow that (and look better!).

Or I can just wait until Dave brings out his NZT coupler, and see if it passes the reliability test, and if his coupler can be used with your box (or a similar one), that might be the best of all worlds.

[GaryHinshaw]

jb, I think the biggest problem with FT's is their cost and niche availability.  But I do think you could run them in a club environment without too much trouble.  The test train I'm running them in has a real dog's breakfast of couplers, wheels, etc. and they're working fine.   Unless your track is really wonky, I don't think you'll have any more problems than usual with coupler height since FTs are not that must shorter (vertically) than MT's. 

My biggest concern with extended draft gear is coupler overhang on curves. Even with 18" radius curves, I have had cases where an overhanging coupler forces a neighboring truck-mounted car off the tracks:



In this shot the car on the left is a Red Caboose beer car with a bound-mount AZL coupler (which is very stiff in it's centering), the car on the right has a standard MT truck-mount and it has been twisted off the rails by the overhang.   I'm hoping the new pockets and the freer FT couplers will fix this problem, but I haven't tried it yet.

As noted above, it would be fairly easy to resize this pocket to accommodate Accumates or Mchenry's, but that's not anything I have time to do myself.  If there was sufficient interest, we could explore ways to make that happen.  It would be more challenging to make this style of extended pocket work with MT's, and it's probably not worth the trouble.

If you'd like to try a few pockets let us know, but you'd have to scrounge up your own FT's...    I need to coordinate with Ed about the logistics for another order, we'll post specifics here when we have a plan.

Cheers,
Gary

[ednadolski]

Say Gary, that's a fantastic job on the hopper install, thanks for posting that!    I'll have to get myself some 0.040" styrene and try that out (a 00-90 screw is easy enough to trim with a rail nippers, but getting it flush with the top edge of the pocket takes some filing).

I've installed these FTs and pockets on about 10 cars so far.   Seems that each car takes a bit of tinkering to get the right height.  Some cases are a matter of lowering the carbody (which for most models is an improvement anyway).  I've been using the MT gauge and trying to get the FT coupler to line up with the vertical mid-line of the gauge.  As long as the FT is no higher than the top edge of the MT, or no lower than the bottom edge, then it seems to work OK.

I've been looking forward to putting these together into a train to see how they operate, so I've finally got my old Loop layout set back up (this took a bit of effort to get lights, power, wiring, and some rudimentary staging).   Here are a couple of videos to show the results.   This first one is a 10-car train, with every car plus the loco installed with the FT couplers.  The cars also are all-metal wheels (I'm planning to ban plastic wheels from my layout).  I'm running it uphill with the loco pushing all the cars, to see how the body-mounted couplers work out on a fairly stiff grade (over 2%) and 18.75" curves.  Looks like it runs pretty smoothly (hopefully the YouTube jitter isn't too bad for most folks -- I have a slow connection):

This next one is the same train going downgrade.  Best part is, I can run the train at very slow speed, and these FT couplers completely eliminate the 'slinky' effect:

Finally, just for comparison, here is a similar train also running downhill.  This is the same loco, track, and speed setting as the previous clip, the only difference is that these cars all have MT couplers.   As you can see, the slinky effect is very pronounced, esp. on the last few cars:

I did one other test, tho I don't have a clip of it:  I put all 20 cars into one train, with the FT-equipped cars for the back half. With two locos pushing from the rear, the entire train runs uphill and thru all the curves without a hitch.   So far I have not had any unexpected uncouplings with any of the FT-equipped cars.

I'm continuing to install these FTs on more cars and engines, including some like the BLMA reefer with longer overhang.

Thanks for checking these out! 

Ed

[GaryHinshaw]

Now that's a Tehachapi video!!  (Needs sound though.  )

Beautiful work Ed.  I'd like to see how you handled the LPG tanker as that is one of the next ones on my list.  I agree that fine-tuning the coupler height is one of the most finicky parts of the operation, but I think that true of any body-mounting campaign.  I have an idea for some additional shims to include in the next fret.

-gfh

P.S. I'm really surprised how bad the slinky is on that last vid.  I don't think I've ever seen it quite that bad.  Did you start jerking with the controls after the loco was out of view. 

[ednadolski]

P.S. I'm really surprised how bad the slinky is on that last vid.  I don't think I've ever seen it quite that bad.  Did you start jerking with the controls after the loco was out of view. 

If only that were the case, then I could have saved myself a heckuva lot of time and money.  Unfortunately, it really is like that, and it does it every time.  Anyone who doesn't believe the video is more than welcome to come over and see it in person.  And there isn't anything special about this set of cars, it happens on anything with MT couplers.

Ed

[ednadolski]

Needs sound though. 

Definitely!  The furnace running in the background doesn't quite cut it!   

Ed

[DKS]

While I am still not encouraged to release all of the ProtoMate details yet, I can say the following, in the event it has any impact on this (or any similar) project...

The ProtoMate coupler should be a drop-in for most existing modern coupler pockets; that is, the shank hole is the same diameter as that of the Accumate, etc.

Shank will be offered in multiple lengths (probably two for starters).

On the initial version, the knuckle will be centered horizontally along the shank. Other variations will come in time.

Knuckle size for the N scale version will be in keeping with competitive products, although it may be very slightly taller than some for greater reliability, with true zero draft angle on the inner faces. The Z scale version is actually intended to be a "finescale" N scale version, and may be slightly smaller than existing Z scale couplers. Shank parts will be the same as the N scale version so they can drop into existing pockets.

Other notes:

No slinky; the spring is not linear, nor is it in line with the shank.

Trip pin is fitted in a hole that runs the full height of the knuckle, so it won't pop out.

Both halves of the split shank engage the fulcrum, so they will not blow apart.

No parts (such as plastic springs) extend backward beyond the shanks where they engage the fulcrum, so the required pocket size is the absolute minimum.

[pedro]

David, I hope you're prepared to offer 100-packs. Seriously. This is coming at a perfect time for me. I'm in the middle of changing eras and have sold almost everything I own in order to start over. Going all body mounts and Z scale couplers. Can't wait to see this in person.

[peteski]

Thanks for the peek behind the curtain David!

[Ed Kapuscinski]

You know those moments where you see something and thing "there's the future"?

I just had one of them popping into this thread, not having have checked in in a while. Particularly, these:

Wow. Just wow.