N-Possible Coupler Announcement (Nashville 2022)

[Sokramiketes]

Glue it! It’s important that the spring remain centered.

The black rubberized CA is great to glue it in place. That way we only have to deal with one type of URS shim, rather than a range to fit multiple box styles. I would have been annoyed to have to keep multiple shims in stock, like I am with any axle length that’s not standard either. lol.

[dangerboy81]

I have put a few in Microtrains truck mounted coupler boxes, I don't know if the retro coupler boxes are meant for that, but with a dab of CA to hold the centering piece in place, they are working out for me. These things are GREAT!

[ednadolski]

I've now hosted 6+ sessions with these couplers and the operator reviews have been uniformly positive.  Spontaneous decouplings and slinkies are a thing of the past.  It does take a bit of dexterity (and good light) to get a pick* in place but it does work.  (Personally I have often found it easier to pick N-Possibles apart than it is Kadee HO couplers.)  I still only have about half of my on-layout fleet converted now, so we still have to manage conversion cars, which can be a pain in a complex switching environment.  But that is a temporary issue.

* RE picks: I have had good luck taking a used fine-point MicroBrush and snipping the brush head off at an angle:



If it frays a little bit, that's even better. 

I've only done a few of these so far (SBX only), so I feel like a dweeb for saying, but I've not been able to get these to couple/uncouple (esp. the latter) as smoothly as everyone seems to be reporting.   When coupling, it seems that the couplers somehow are not aligning quite right, as the target car may push away, or else I have to give the cars a little nudge w/my finger to get them to connect.   With uncoupling, even tho I have used several different picks (trimmed micro-brush, dental pick, steel pin, and machinist scribe) I can only some times get them to pop apart as smoothly & effortlessly as I have seen @turbowhiz using the 'tap on the joint with a sharp object method' in a couple of the demo videos.   Is there a particular spot that the pick needs to hit?  I've been aiming for the point where the curved end of the knuckle contacts the corresponding 'hollow' of the other coupler.   It also seems there should be some sort of little 'flick' or 'twist' to ensure that the couplers separate, but I have not quite developed the knack for that just yet.

My suspicion is that there is something off with my prep and/or assembly process that is resulting in this stiff/sticky operation.  Initially I was not filing down the support stubs on the outer ring of either half, so that had introduced some drag/binding, but including that has made a substantial improvement.  I don't think that I have over-tightened the mounting screw, or installed w/the pocket offset/skewed to one side (AFAICT anyways).   Are there any other hints/tips/tricks I should try, in either the assembly or the operation?

Thanks,
Ed

[GaryHinshaw]

Gosh Ed, you're such a dweeb. 

I would focus on achieving "kiss coupling' before I worried about uncoupling technique.  The main thing to make sure of in the completed installation is that the coupler recenters freely when displaced in either direction.  Can you post any photos of installs that are giving you grief?

[garethashenden]

Did you lubricate the shanks with a pencil? I found it made a big difference.

[Sokramiketes]

Some troubleshooting notes for when they arn't kiss coupling:

1) The coupler must be centered, which means that it depends almost *to the coil* how the spring is put down over the splitter.  If the coupler is listing to one side, you may get knuckles bouncing off each other.  (If you are one coil off, it seems to be better for it to be toward the knuckle side and not toward the thumb side.)

2) Couplers centered on car end.  Yes, more precision is needed than an MTL coupler.  I used to wing it a lot because I'm lazy.  Now I have a printed centering jig to hit dead center and straight when drilling a new hole.

3) Another possible cause of couplers not coupling (and bouncing off each other) is if the couplers are angled on the underframe.  They need to be dead level across.  So if you're mounting a scale box and have any flash or other molding defect that doesn't allow the box to seat fully flush on the underframe... they will appear to spread knuckles to couple but cannot engage due to the angle. 

4) A final tweak, sometimes you need to take some slop out of the truck bolster.  If the pin or screw allows a lot of side to side play, remember that affects the car centering on the track, and therefore coupler centering as well. 

And yes, if its taking force to get them coupled, that means it's probably taking more to separate them as well.  Like Gary said, get them to couple first, then you'll likely find they pop apart when poked with an uncoupling pin. 

[GaryHinshaw]

FWIW,  I have yet to encounter a scale box install that required lubrication.*  I know Andrew recommends this; I just have an aversion.   

The post geometry in the scale box makes it almost impossible to over-tighten the screw.  I have had a few cases where it was helpful to chamfer the inside-back edge of the lid to make sure the spring was not binding.   The most important thing to check is that the coupler recenters freely in both directions.

*I'd estimate that I've done ~150 SBX installs now.

[learmoia]

I've only done a few of these so far (SBX only), so I feel like a dweeb for saying, but I've not been able to get these to couple/uncouple (esp. the latter) as smoothly as everyone seems to be reporting.   When coupling, it seems that the couplers somehow are not aligning quite right, as the target car may push away, or else I have to give the cars a little nudge w/my finger to get them to connect.   

I had a similar experience with my trial... I had some cars (SBX) that were perfect... but I had an equal amount of cars that were troublesome..

For whatever reason I had the most issues with medium length couplers..

The smaller size coupler and tighter tolerances magnifies the issues you could face in any body mount situation.

I didn't have the patience to go through the fine tuning, so I chose to stick with MTLs..

But once you get them coupled... DAMN they worked good!!!!..
https://youtube.com/shorts/rpWbyPRUhdg?si=FMVEFJgS1qkO8J7k

~Ian

[ednadolski]

Thanks indeed to all for your insights.   I have not yet tried the pencil/lube but I will give it a go on the next batch.  One thing I did notice on closer inspection, was that in some cases the retainer shank seems to have developed a 'droop' relative to the knuckle shank, and I wonder if that may contribute to some binding.   I don;t think I had assembled it that way, but I'd bet that perhaps I caused it from poking too aggressively with the pick.  Another thought is perhaps I did not get enough of the torsion out, when installing the spring onto the retainer half.

It is hard to tell looking from above, but the side view is pretty starkly evident:





Time to fix that up and give it another go. 

Ed

[GaryHinshaw]

That definitely looks like you have some residual torsion in the spring.  I'd also take a close look at how well the box lid is closed on the base.  The shank halves shouldn't splay as much as the one on the right with a properly closed box.   Do those couplers recenter freely on their own?

[Sokramiketes]

Agreed with Gary.  There's something off with the box staying closed.  Possibly it sprung open while screwing it to the car body.  Then a top got wedged.

The spring torsion is also likely a culprit, though when the box is closed it's an issue that just allows a little light leak between shafts.  I mentioned up thread, but if you're having trouble with the spring torsion and the drop test, just align the two coupler halves and install the spring straight afterwards.  It's really easy to snap it in between the mushroom posts.

While I do lube, I don't think it's anything other than a final 2% improvement step.  It is not a solution for other assembly issues, just a bit of *chef's kiss* on operations.  I do it mainly on the surfaces I sand with a 600 grit stick, to repolish the surfaces that touch the coupler box. 

[turbowhiz]

Thanks indeed to all for your insights.   I have not yet tried the pencil/lube but I will give it a go on the next batch.  One thing I did notice on closer inspection, was that in some cases the retainer shank seems to have developed a 'droop' relative to the knuckle shank, and I wonder if that may contribute to some binding.   I don;t think I had assembled it that way, but I'd bet that perhaps I caused it from poking too aggressively with the pick.  Another thought is perhaps I did not get enough of the torsion out, when installing the spring onto the retainer half.

It is hard to tell looking from above, but the side view is pretty starkly evident:





Time to fix that up and give it another go. 

Ed

For sure, the boxes are definitely not correctly assembled at this point... Torsioned springs will not create that much gap in a properly assembled box, and its evident that the box is not fully mated together in your pictures. You should be able to have the box tightly screwed on the car, and no amount of aggressive picking will cause it to come apart like that if its properly secured.

The fit of the box is very precise... So take your time and gently assemble the top/bottom sections, they will fit together precisely but you need perfect alignment. The box top interfaces with a subtle friction fit around the main post, and the front of the section interfaces into the box bottom. I suspect you didn't have the boxes fully mated when you first mounted them to the car in this case, or they came apart as you mounted them.

I'm wrapping up development of another line of boxes, which are more of a 1015 type outline. They are easier to work with. Although intended for locomotives, they also can also be used on rolling stock too at the expense of less scale appearance when viewing the end profile. They also have more lateral coupler travel then the scalebox.

[Peter Amling]

If anyone is looking for more couplers stateside, Pioneer Trains has these in stock.
www.pioneertrains.com

[Mark5]

If anyone is looking for more couplers stateside, Pioneer Trains has these in stock.
www.pioneertrains.com

This is where I got mine - quick and easy!

Mark

[robert3985]

Just ordered my first batch.  Didn't order any long-shank versions as I don't think I'll need any for my 1947 thru 1956 roster of engines and cars. 

CAN'T WAIT!!! 

Cheerio!
Bob Gilmore