On Mon, Mar 7, 2022 at 04:57 AM, Robert Ellis wrote:

Earl's comments about draft gear got me thinking.  There are accurate scale parts available to model virtually every component of a freight car, at least in ho. The one exception is draft gear.  Now that there are alternatives to the Kadee #5 that don't require a "coupler box," wouldn't it be nice if someone would produce accurate scale draft gear, compatible with Accumate and Sargent couplers?

I want to thank Eric Hansmann for the nice write-up on the Proto:HO Accumate. However, to answer  Robert's question, truly scale sized draft gear is still in the future. The reason is the prototype draft gear fits in the 12-7/8" space between the center sills. That's just .148 actual inches. I worked hard to get the Proto:HO box narrow enough to match the 20-1/4" wide cover plates typical on steam era freight cars, so it appears the center sills continue through the bolster as they do on the prototype, but at the expense of "borrowing" the depth of the channels the sills are made of. The interior of the box is still about .040" wider than a true reduction of the prototype. Even if someone 3D prints a three dimensional box, it's either going to be too wide to match the sill spacing, or the walls are going to be impossibly thin. I think the best we can hope for is 3D prints of draft keys and the forging they ride in, complete with rivet heads, that can be glued to the sides of whatever box is on the model. The rudimentary draft key detail molded on the Proto:HO box can be sliced right off.

Dennis Storzek
Accurail, Inc.