Sunday, May 06, 2007

The marker lights

These are fitted front and back above the bufferbeams, attached together by cable.

They're a two-part etch. There's enough material for twenty lights but I only need four, so I can experiment a bit.

Once cut down the middle the part-etches can be overlaid. The part with a slit goes underneath to make a hole for the connecting cable.

I make a couple and cut them off but find that even the tiny sliver of solder I've used is enough to fill in the holes.

They're about 1mm long and it's beyond me to remove the solder. Perhaps I should build them with the wire in place.

The thinnest wire to hand is overscale (0.25mm). I glue the other half-etch on top of it.

The wire is very obviously too thick.

I wasn't able to locate any 0.15mm piano wire, but I got some gauge 8 guitar wire (0.2mm).

Eventually I find a method that works for me. Some part-etches seem to be larger than others, so I start with the large ones.

Use the jigs to cut the wire to length. Solder it onto the lower half-etches. Allow enough solder to bring it level with the wire and file flat.

Fix the top halves with epoxy and trim to shape.

The lowest set here uses the smaller part-etches. I'm not sure which are nearer to scale but I think the larger ones look better, possibly because they make the overscale wire less obvious.

Finally, and this may be too ambitious for me, once fitted the front cable should extend round one side of the bonnet, down and across the steps. I've got several metres of soft brass wire to practice with.

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