N-Possible Coupler Announcement (Nashville 2022)

[Maletrain]

Peteski,

The screws that Gary is using are designed for small electronic gadgets, and seem to be called "Mini Phillips Wafer Flat Head Screws" if you are doing a search.

See https://www.ebay.com/itm/404601920459

[peteski]

The Aliexpress link I gave above describes them as "Mini Small Phillips Ultrathin Wafer Flat Head Screw Bolt for Laptop Notebook Phone Glasses".    In the diagram you posted, they are closest to the cylinder head, or the one on the lower left (DE??).  I'd avoid screws with a taper between the head and shaft.

Wafer Flat Head Screw Bolt?  Really? That is so Chinglish.  I guess the screw head nomenclature standards are out of the window.  I know, you just copied the name of the product you bought. Thanks.

And that is PF, not DE (TRW watermark obfuscated the name).

[CNscale]

The Aliexpress link I gave above describes them as "Mini Small Phillips Ultrathin Wafer Flat Head Screw Bolt for Laptop Notebook Phone Glasses".    In the diagram you posted, they are closest to the cylinder head, or the one on the lower left (DE??).  I'd avoid screws with a taper between the head and shaft.

Product names and descriptions on Aliexpress have been known to occasionally be ... ahem ... at odds with standard technical terminology.

[GaryHinshaw]

Far be it for me to defend the Aliexpress nomenclature.  I also have no idea if these screw heads actually following any particular ASME standard.  However, they work fine for me, and I think as long as you avoid a tapered head to shaft transition, you'll be fine.

RE the gauge, height, and hat question, here is a bit more info.  I mounted the base of the scale box directly on to the MT-1055 gauge as shown (using the supplied 00-90 screw):



The result is a perfect match to the MTL coupler height:



The role of the hat is to bring the top of the box to the same height as the top of the MTL box, so it can be a drop-in-place conversion for a standard MTL body-mount.  Here is an example in an MTL NSC 60' box car:



The hat itself press fits onto the box top and provides an additional 0.35 mm of box height, and some additional width.  (The shank in the above example is medium length.)

[nickelplate759]

The Aliexpress web site (per the link from @GaryHinshaw )site says "Max. 1 pcs/shopper, where a piece seems to be a package of 50 screws.  is there a way around that?

[Missaberoad]

@GaryHinshaw

I may have missed this earlier in the thread but what is the reason behind using m1.2 screws vs 00-90? Im assuming this requires re drilling and tapping factory holes?

[garethashenden]

@GaryHinshaw

I may have missed this earlier in the thread but what is the reason behind using m1.2 screws vs 00-90? Im assuming this requires re drilling and tapping factory holes?

My reasoning is cost. I wanted a flathead screw, the sort with a taper to the threads, to mount MTL couplers and not have the axle hit the screw. While 00-90 screws in that style are available, they're expensive and hard to find. Metric screws are cheap and readily available. One thread is 1.20 mm in diameter, the other is 1.19mm.

If there is a factory hole I'm going to use the factory screw, or at least something with the same thread. But if I'm making a hole, either in something with truck mounted couplers or on a kit, its going to be M1.2.

[GaryHinshaw]

The Aliexpress web site (per the link from @GaryHinshaw )site says "Max. 1 pcs/shopper, where a piece seems to be a package of 50 screws.  is there a way around that?

That's odd.  It does not say that when I open the link now, and I bought 8 packs of 50 when I made the initial purchase.   

Also, I echo Gareth's comment about why M1.2: cost and availability.  I use them for my scale box installs but I generally stick with the factory screw if I'm doing a retro-fit.  Of course 00-90 screws will work just as well if you have a good source.

[turbowhiz]

For reference, there are dimensions for the SBX on the assembly instruction page on the N-Possible site:

https://www.n-possible.com/resources/sbx-assembly-instructions

[turbowhiz]

What shank length do you recommend for (A) typical 1950s box cars and coal hoppers, etc. and (B) pilot couplers for Bachmann 4-6-0, (C) Bachmann 2-8-0 (Spectrum version), and (D) BLI USRA Mikado?

Short shanks for the 1950's freight cars typically. The 2-8-0 spectrum most certainly a "non-standard" install; I used a medium shank coupler, and the bottom half of the scalebox glued to the OEM pilot. I also needed to modify the leading wheel carrier for clearance as I recall.



Looking at the 4-6-0 pictures on Mark's site, I'm thinking a medium for that one too... URS in that scenario in theory should work, but I don't have an example to try.

I also looked at the BLI stuff at the NTS, specifically for coupler setups. A short or medium URS should in theory work, but again, not practically tested.

In the pipeline is a more steam pilot specific configuration. Bespoke replacement pilots I suppose could become a thing, but I need to see how things go.

If anyone has some scrap BLI steam chassis they say got as part of the recent random useless box of parts sale they're willing to send to me for the cause, I'd certainly appreciate it. Just really need some minimum number of drivers, ideally the pilot wheels, and the pilot....

[Rasputen]

I have some complete functional models of BLI 4-6-2s and 2-8-2s that I can send you as loaners if you wish, also Kato 2-8-2s, etc.


Thank you for attending the National Train Show!

[nickelplate759]

That's odd.  It does not say that when I open the link now, and I bought 8 packs of 50 when I made the initial purchase.   

Also, I echo Gareth's comment about why M1.2: cost and availability.  I use them for my scale box installs but I generally stick with the factory screw if I'm doing a retro-fit.  Of course 00-90 screws will work just as well if you have a good source.

Still shows "Max. 1 pcs/shopper for me -- But I can put more than one in my cart if I do them one at a time -  and they show as separate items.
I wonder if it has to do with the parts being flagged as a "Welcome deal" with a 32% discount?

More important, what do you recommend for M1.2 taps?

Regards,
George

[Ed Kapuscinski]

I used a medium in the pilot of my 89 project (a Bachmann 2-6-0). I had planned on going short but was shocked at how long the prototype stuck out.

https://www.railpictures.net/photo/700609/

[wmcbride]

Still shows "Max. 1 pcs/shopper for me -- But I can put more than one in my cart if I do them one at a time -  and they show as separate items.
I wonder if it has to do with the parts being flagged as a "Welcome deal" with a 32% discount?

More important, what do you recommend for M1.2 taps?

Regards,
George

I could only put in one type in my cart. When I added another (medium) to the existing (short), the CVR shopping cart replaced the exisitng item with the added. I tried several times and just kept ping-ponging back and forth with the result of only having the latest addition of one item in my basket.

[Sokramiketes]

I had a chance to test a train of these on the Modutrak layout at NMRA Novi.  Wow. 

Modular layouts, even Modutrak, can sometimes have some messy joints that test coupler's verticle range.  So the big question was, will the smaller scale coupler head have any issues separating at module joints. 

Watching these couplers navigate joints, I'm impressed by their ability to hold at the outer edge.  But it makes sense.  There's no draft angle to contend with, like a Micro-Trains coupler.  And they arn't made out of slippery engineering plastic.  So they hold at the edge even better, despire their more scale height.  Add in the lack of coupler bounce, and these will ultimately prove to be more reliable I'm sure. 

There's an arguement to be made that these are better than MTL even for the N-trak and FremoN modular layout runners.  And that's pretty impressive.