Stuart build questions

[Nick WelburnParticipant @nickwelburn]

I’ve made my crankshaft and piston for the 10v today. I’ve got a couple of questions.
the bore of my cylinder is rough. Even with a little oil it doesn’t let the piston smoothly drop.

I guess it needs a hone. But how?

Secondly in a moments stupidity I started on the block that the piston rod goes into. I decided to start by milling the top and bottom flat. To do this I cut the casting bar off. I now realise I needed that to use that to turn the outside diameter down. Any cunning ideas for this?

Or should I just order an new one and think about what I’m doing before I start next time

[Nick WelburnParticipant @nickwelburn]

[Former MemberParticipant @formermember12892]

[This posting has been removed]

[JasonBModerator @jasonb]

The cheap "brake cylinder hones" on e-bay will do, probably have to be the two stone one on that 3/4" bore.

You could tap the crosshead for the piston rod and screw it in then use the rod to hold it by in a collet, split bush or 4-jaw so the rod runs true while you turn the OD to fit the trunk guide. Bore and finish the trunk guide first then make the crosshead guide to fit

[Nick WelburnParticipant @nickwelburn]

Will a 5ba thread hold the part while I turn it? Maybe if I drill and tap deeper into the block and super glue it?

[JasonBModerator @jasonb]

With light cuts and a sharp tool it will, you can always bring up the tailstock ctr for added support, superglue won't make much difference.

[mechman48Participant @mechman48]

'The cheap "brake cylinder hones" on e-bay will do, probably have to be the two stone one on that 3/4" bore.'

+1, Exactly what I have, & used on my !0V, works a treat & not expensive.

George.

[Nick WelburnParticipant @nickwelburn]

Ok – sorted that bit and learned not to start cutting without a plan for all operations! Will get a hone on order quick zip with the dremel and a polishing pad has helped considerably. May try the dremel with some valve grinding paste and see what does.

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