Shopsmith Forums

I could use a little help . I remember reading about some chemical that you could use if the rust pits on tubes where deeper than you could sand out. Paint it on then sand or buff off the excess. I want ot say it was called petrol? IF anyone knows what I can't remember. Thanks. Product name please. Thank DOW

DOWeaver wrote: ↑Sat Mar 16, 2024 1:46 pm I could use a little help . I remember reading about some chemical that you could use if the rust pits on tubes where deeper than you could sand out. Paint it on then sand or buff off the excess. I want ot say it was called petrol? IF anyone knows what I can't remember. Thanks. Product name please. Thank DOW

I believe you are thinking of Penetrol.(?) Consider getting rid of the rust first with Evaporust or alternative.

- David

To show you are a real ShopSmith guy, try Nick Engler's solution.
https://www.youtube.com/watch?v=qYgnHDB3VNI
You might have a great story to tell.

Doc

Penetrol isn't a filler but it will stop deep corrosion from getting worse. Wax will fill pits somewhat if you want a smoother surface.

Thanks all. Have already finished the tubes on five SS but couldn't remember the name of the stuff. Needed the name because I also rework tools for hand tool woodworking and sometimes want them to look better before paint or taking them out for use. Thanks again DOW

FWIW shallow pits are not a functional defect. It is more of an appearance thing.

DOWeaver,

You said,

I remember reading about some chemical that you could use if the rust pits on tubes where deeper than you could sand out.

I believe you already know this but others looking for advice may not. Sanding of the Way Tubes is not the best method for rust removal and evening out rust pits. Removing metal from the Way Tubes decreases the diameter and thereby causes the Headstock and Carriage to not fit as well, reducing the precision of the Shopsmith. This would be especially true if deep sanding was done only in areas of heavy pitting leaving the Way Tube with a uneven diameter over the length of the tube. Because they are a "polished" bare metal tube some very light sanding can be done. I have done it myself for Shopsmith restorations after the rust is chemically removed.

As JPG said, For What It's Worth "shallow pits are not a functional defect. It is more of an appearance thing." As much as we like to have our tools looking sharp there are things that are better left unchanged. This is not to say leave them unprotected.

My recommendation is to remove rust by electrolysis and minimal polishing then rust prevention(waxing)..

JPG wrote: ↑Sun Mar 17, 2024 12:37 pm My recommendation is to remove rust by electrolysis and minimal polishing.

Do you use a bathtub full of acid for tubes?

I need to alter my recommendation!

Although electrolysis is 'good', using evaporust is better with long tubes. Evaporust reacts with rust by a chelation process that leaves the base metal(steel/iron) unaffected.

A piece of pvc sewer pipe(2") with one end plugged and a smaller pipe plugged at both ends to take up internal space allows 'soaking' the SS tube in about one pint of evaporust.

It will remove rust over night unless grossly rusted(crusty).

Auto supply stores is a potential source for the evaporust.