Well, I've spent the last couple of weeks de seaming and polishing the three main gearbox castings to get them as good as I can. I've done a bit of googling to find out how to keep them this way, once the bike is assembled and on the road and it appears that applying pink Windowlene or Turtlewax will stop the casings from getting furred up. If anyone can confirm this, or give me any other advice, I'll be glad to hear it.
I decided to put the outer cover up in the mill to re-machine the counter bores for the fixing holes, as these were uneven, due to 60 years worth of over tightening bolts.
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I held it down on a plate in the vice and swapped the screws around to get to all the holes.
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I also increased the spotface area around the gearchange shaft, so as to give me more room to accommodate a hand change lever.
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That's the cover just about finished. I'll give it one more polish before applying the Windowlene/ Triplewax.
I stay on after work to do this, as it's lighter and warmer than the garage and I have the machines available.The trade off is that it's fucking cold riding home.
The plan for this week is to make the hand change lever.
I've got a lump of 12mm Ally, left over from a machine mod, so that's what it's going to be made from.
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This is roughly what it will look like. I'll blue up the plate and mark it out with Trammels/ dividers to get the exact shape, then drill it before bandsawing it out.
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I may have to put a "set" in it, if my knee gets in the way.
I've got to find a suitable knob for the top (it won't be an 8 ball) so that I can tap the top to suit, hopefully 8mm.