The kit has a rigid, fold-up chassis which is perfectly useable, especially if fitted with some form of compensation.
However, although the full size loco doesn't have any inside frames, I wanted to try 'proper' S7 width frames and sprung hornblocks, partly as preparation for the Wantage steam locos.
Also, while I have a general design idea, the details will evolve as work proceeds; and that's much easier if the frames are separate units till final assembly.
So... two frame blanks were soldered together and the outline and axle hole positions marked. At each end a further hole was added on the axle line.
Once clamped to a piece of 12 mm ply, the whole unit was clamped to the drill table, using a 4 mm pin point axle to locate in the hole marker of one of the end holes. Using successive drill sizes, this hole was opened up to 2 mm. With the ply still clamped, the metal was removed, and it's hole gently broached to a snug clearance fit on 2 mm steel rod. ( more 4 mm axle. ) Using the drill as a press another 2 mm rod was pushed into the ply, and the metal replaced over it. This process was repeated for the remaining three holes, the two axles opened to 1/8", the last to 2 mm.
I now have a jig that will locate the axleboxes relative to the frames once I have cut out the outline and hornguide slots.
View attachment 13110
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