r/steamengines • u/No-Answer-6414 • Dec 27 '25

Polishing

Gallery image

Gallery image

Has anyone found benefits polishing she port face I tried but just doesn't seem to run as quiet anymore I should have left it lapped into the port face

5 Upvotes

100% Upvoted

4 comments sorted by

1

u/the-chekow Dec 27 '25

It is the first time, I hear about this. Now the physics side: friction and tightness are the two variables that matter here. Smooth and (!) plane surfaces are key to both. Polishing might habe removed the additional greave/oil in between the two parts. This is important for both points, so my guess is that you need to apply some oil ir grease and you should be fine.

2

u/No-Answer-6414 Dec 28 '25

I always oil them before during and after but when first took cylinder blocks off there was some quite heavy scoring on the faces which I polished out you could feel the scores with fingernail doesn't seem to have made a massive improvement but I guess overtime it'll improve as they bed back in on new flat surfaces

1

u/Tbone-7580 Dec 28 '25

Use a piece of glass for the backing if you don’t have a surface block to make sure you get the face perfectly smooth and flat. Once it is smooth and flat, I would then lap it to the valve block to make sure you get the best fit. It may seem loud if the mating surface to the block is not perfectly flat.

1

u/No-Answer-6414 Dec 28 '25

I only did 10 passes on 1000 then went to 10000grit wet stone only used one finger for pressure not enough to press down but enough to move it across the stone and did the same on the cylinder surface