Bore ring gage corrosion protection / polishing

Apologies if this is a silly question. I did search and was unsuccessful.

I am tearing down a race engine and plan on checking tolerances myself. I got a Mitutoyo bore gage and can repetitively and consistently using a used 88mm ring gage.

I found here a lot of good options to protect from corrosion like Starrett M1.

The ring is not rusted but the metal is 'dull'. Is it a cardinal sin to polish a standard with something like Mother's or an equivalent polishing agent before applying corrosion protection.

I understand the corrosion protection needs to be removed to measure in tenth. Does a polishing agent alter the dimensions of a ring gage ?

Thank you for sharing insight with a newbie.

I wouldn't do it. If there is no rust, just use any protective oil.

I agree. Don't use an abrasive polishing compound. If anything use a mild scotch-brite and oil. ONLY by hand, no powered equipment. Even that I would only do if you can feel something abnormal on the surface.

Tallwithhair said:

Apologies if this is a silly question. I did search and was unsuccessful.

I am tearing down a race engine and plan on checking tolerances myself. I got a Mitutoyo bore gage and can repetitively and consistently using a used 88mm ring gage.

I found here a lot of good options to protect from corrosion like Starrett M1.

The ring is not rusted but the metal is 'dull'. Is it a cardinal sin to polish a standard with something like Mother's or an equivalent polishing agent before applying corrosion protection.

I understand the corrosion protection needs to be removed to measure in tenth. Does a polishing agent alter the dimensions of a ring gage ?

Thank you for sharing insight with a newbie.

Click to expand...

.
.
the best ring gages are hard chrome plated. they wear much slower and are much more corrosion resistant. some wait til ring gage are worn and have it reground, chrome plated and ground to size. older ring gages get scratches and taper wear.
.
most wipe coolant off and spray with M1, if its in long term storage you might need vasolene, or astro-kote. vasolene or petroleum jelly stays softs, sticks to fingers (messy), astro-kote is asphalt tar and mineral spirits which when dries leaves a thicker coating usually non stick coating (like a wax). M1 I believe is same just less percentage of asphalt tar so leaves thinner coating.
.
multiple layers of astro-kote you can use a putty knife to scrape off, it also softens and comes off with mineral spirits. some spray furniture polish some leaves a similar wax like coating.
.
obviously if ring gage is very rusty you can use a fine nylon abrasive cloth, obviously rust pits on spots, the bore is getting moon craters in the millionths of a inch, .0001" bore indicator gage you might see this

many put ring gages in cnc so its at same temperature as coolant and part. if you forget and leave in machine over night ring gages often get rusty.
.
most take out at end of work shift, wipe dry and spray with M1. wouldnt be first time somebody forgot and left ring gages in the machine