This bogie wagon frame unit combines with my N-gauge/2mm scale Coil EG floor model and either of the Coil EG cradle units to make the steel coil carrying conversion of the Warflat wagon. The tumblers are to hold N-gauge society or Graham Farish diamond frame bogies (which you will also require, along with wheels) on the locating points on the underside of the floor. You can use the corresponding parts from the Parkwood / N-gauge society chassis _instead_ of this 3D printed chassis, but the kit is not produced currently. In any case, the fine detail on this 3D printed model is more accurate for the coil conversion. Apart from bogies and wheels, you will also need fine wire and handbrake wheels (e.g. etched brass ones by Ultima) and bufferheads (e.g. turned brass ones from Parkside Dundas). When assembling, the planked walkway which goes between the cradles goes towards the end of the wagon furthest from the handbrake wheels. There are at least two distinct chassis variants for Coil E & G conversions, and I do have the slightly lighter built (earlier, less rivets, ex Warflat 45t) version ready to upload as soon as I'm happy with the fit to the other parts with this design.
BTW: The four-spoke design in my Shapeways brake handwheel model is suitable for this chassis.