Regular readers of the list are aware I am a sucker for the unusual, so when Bob Werre offered a kit for the RailMaster RSD-4/5 including the Steam Depot drive from the Click collection, I snatched it away.

John Agnew has confirmed that he never sold any of his Alco RS-2/3 kits with an RSD drive (and presumably that North Yard or any similar supplier ever made one), but that he sent a number of those kits to John Chappell, owner of Steam Depot, to be sold with the latter's "Curve" drive developed especially for that.

I expect there must be others out there, but I KNOW of only one other in existence, and that fully-assembled.

I finally got the drive put together and thought to share the result.? So far as I know, the original kit included a Sagami motor, but that was missing from my purchase and the firm long out of business, so I adapted a Canon CN-22 motor to replace it.? With Sagami and Mashima both out of business, the Canons are the only readily available can motors suitable for most smaller locomotives.

As I've noted in previous posts, Steam Depot developed other drives for S scale diesels, including AAR type A switcher sideframes, Alco Blunt side frames, and both Blomberg (EMD) and AAR type B sideframes for road locomotives.? ?Although he went to some trouble to manufacture all from original masters, whoever did those masters apparently didn't allow for shrinkage in casting, so some of them are about 10% undersize.