Plan to build....steam!!

[Jasonb]

I generally don't ream cylinders I bore them.

Unlikely to get a brake hone to fit this engine so turn down a bit of scrap aluminium or even hardwood and use that as a lap, charge with 600g silicon carbide powder and oil mix

 

[Maxjon]

I generally don't ream cylinders I bore them.

Unlikely to get a brake hone to fit this engine so turn down a bit of scrap aluminium or even hardwood and use that as a lap, charge with 600g silicon carbide powder and oil mix

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Yes I'd be confident of a nice finish in the CNC, not so much on my lathe in the shed at home.....I will leave a heap of stock for practice feeds....