New HO narrow coupler box now available



With regards to this new draft gear box being compatible with Sharon couplers, as long as this replaces the Accumate #1031 draft gear box, it will work for Sharons.  From my understanding, the #1031 draft gear box is the only one Sergents has been using for their HO scale couplers.

Duncan, I'm planning to buy a few sets to test them out.  I can discuss on the side with you and the club to share my feedback.



I just pulled up the Accurail website again, after looking at the draft gear description on Smoky Mountain's website.  The Accumate part # I originally posted, #1031, is for an order of 25 draft gear boxes.  The part number on the Smoky Mountain website shows the new draft gear box replaces part number 1020.  Strangely, Accurail puts the draft gear boxes in two different places on their part website, and the location of #1031 shows they fit Sergent couplers, whereas the location part #1020 doesn't state that.  Regardless, they're still the same draft gear, so the new Smoky Mountain design should have no problem fitting our Sharon couplers.

Sorry for any confusion I may have caused.

Take care,



Hi all,

I received my first batch of draft gear boxes from Jim, and assembled a couple last night with the Sharon couplers.  Attached here are photos of the coupler boxes with the couplers installed.  I'm having some difficulty posting photos in my photo album, so I hope the attachments come through. 

I assembled these with the centering spring option. Couple of observations on these new draft gearboxes.  They are wider than the Accumate draft gearboxes, so for our HOn3 application, I envision some filing down of the sides to allow the trucks to swing further left and right.  This will not be an issue for HO standard gauge applications.  Also, with the Accumate draft gear boxes, they're too long to fit on a narrow gauge freight car, so trimming of the length is necessary for them to fit between the end sill and the bolster.  The same is required with the new draft gear boxes.  I don't see this being an issue that would affect the ability of the centering spring, but it may require removing enough of the draft gear to render the second mounting hole unnecessary.  As is typically the case with us narrow gauge modelers, we have to make modifications to make things work.

Regardless, I like the design, and it's nice to have this draft gear available to us. I'll definitely be purchasing more, and I recommend them to my fellow modelers.  With more operational trial, I'll let you know what I think of the centering spring option.  Not having had this option in the past, I don't really see myself using the centering spring, but it's a nice option to have available for those who prefer it.

More to come.

Take care, and have a great weekend.


Jim King <jimking3@...>

Thank you, Jon.  I get emails in digest mode and Yahoo strips all attachments so I couldn’t see your pix.  Can you email them to me directly?


I’m glad you like the parts.  John Degnan did a “little” arm-twisting to get me to make these parts because the Accurail boxes are so hard to find and there’s no other option for Sergent users in HO.  Our goal was to get as close to the Accurail box dimensions as possible (it has the same opening) but improve the outer detail, such as the frame extensions, coupler key/wedge/rivets and the buffer block features.  Self-centering was a major reason I agreed to take on this project because that is a feature the Accurail box could not provide and has been requested by many Sergent users over the years.  I re-entered HO in March 2017 (for personal modeling, not resin kit manufacturing) and plan to give Sergent couplers a real test on my equipment … having self-centering option is important to me, too.


I don’t plan to produce an HOn3 version because the market size is a fraction of standard gauge market with is already small.  My 2nd product, a Kadee whisker/Sergent compatible shank box, should be shipping by the 2nd week of Feb.


Jim King