Any (but keep it clean) - Accelerator pump shaft bellows improvisation

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Mon 20 Mar 2023 06:14
Any (but keep it clean) - Accelerator pump shaft bellows improvisation - edlithgow
I posted earlier a possibility for this, in someone else’s appropriately titled thread.
That post got Guantanamoed, so perhaps a veil should be drawn.
Wouldn’t have worked anyway, due to petrol incompatibility.
I patched it up with superglue and PTFE tape, so didn’t need one, but it’s escaped.
Must have stuck to something (think I would have felt it on my bare feet, so something else, like an elbow) since it not tiny (about 1 cm Diam) and the shower room is. Sticky veg oil sticks again.
MIGHT be possible to do something with the bellows bit of a bendy straw, though it would need a flange, possibly a job for the dreaded RTV.
I have seen little polythene bellow pipettes in a makeup dept somewhere, but doubt I can when actually looking for them.
Any ideas (apart from buying an actual car. I know that one)?

Edited by edlithgow on 20/03/2023 at 06:21

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Mon 20 Mar 2023 06:25
Any (but keep it clean) - Accelerator pump shaft bellows improvisation - paul 1963

Carve a pattern from wood, make a mould then cast one in silicon rubber...

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Mon 20 Mar 2023 11:24
Any (but keep it clean) - Accelerator pump shaft bellows improvisation - edlithgow

Carve a pattern from wood, make a mould then cast one in silicon rubber...

I suppose that would be t”the proper” way to do it. Bellows is a pretty elaborate shape, likely to give mould release difficulties, plus Permatex, at least, say their RTV shouldn’t be exposed to petrol. At the moment I’m thinking along more half assed lines, maybe involving a cut down toothpaste tube with a mini “stuffing box’ style shaft seal in the top (though prop shafts rotate rather than move axially
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Mon 20 Mar 2023 23:44
Any (but keep it clean) - Accelerator pump shaft bellows improvisation - edlithgow
Shoulder of the tube forms a flange. Top of the tube has a couple of layers of thin polythene sheet trapped between the cap and the neck, with a couple of layers of PTFE thread tape, and a smear of silicone grease, between them. Shaft passes through a piercing in these.
I dropped the boat prop shaft stylee “rope seal” (waxed dental floss) idea due to drag on the shaft.
That’ll have to do for now
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