The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: RDfella on 10.01. 2025 16:30
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MY K2f points taper had been got at by some previous urchin and the 'key' area on the taper was butchered. Couldn't find a decent replacement so bought a new one. Came yesterday - and doesn't fit. Wouldn't seat in the armature, so I carefully filed the 'key' as it was quite proud and the keyway is only a few thou deep. Still didn't fit. I eventually discovered the taper didn't match the armature by some margin, so set about repairing my old one, something I had been trying to avoid.
I stripped it down & clocked it up in the small lathe. Turned off the old taper & bored the plate hole 10mm (I used an endmill, as a drill was likely to wander). Then turned up a new taper from bronze (it's aprox 9 deg on the compound-slide), leaving a register on the back to locate in the plate. Bored it 7mm and cut off. Then silver-soldered it to the plate (didn't think soft solder would be strong enough) and re-assembled. Yet to decide whether I'll make a punch and jig to create a new 'key' or whether I'll fit a small pin instead. Then I'll do the same with the new unit so at least it's functional.
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Loving your work RD!
What is it with tapers on these pattern parts, they never seem to be right these days.
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Not even on the tapers on petrol or oil pipe unions.
I hate pattern shite.. *sad2*
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They make it look the same but pay no attention to whether it fits or not. I don't think they know or care what it does.
We only see how it fits but the metals they use are also a big problem, with tools I find they just use carbon steel so its hard but snaps when you load it up.
I've had some (car) brake parts that were so soft they were dangerous.
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i think maybe they use our exported tooling and don't compensate for wear?
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A mate of mine has a cnc machine shop and also owns and supplies parts for a10s. He tries everything he makes on the bikes before he offers them for sale. Why can't all suppliers do this ?
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Hi BSAreg, Are you suggesting they eat into their profits by spending their valuable time testing the fit?? What an outrageous thought. *sarcastic*
Col
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Hi BSAreg, Are you suggesting they eat into their profits by spending their valuable time testing the fit?? What an outrageous thought. *sarcastic*
Col
You're right, why would they when the customer does that for them. 🤔