By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Forum House Ad Zone

Cleaning corrosion from polished cast iron parts

All Topics | Latest Posts

Search for:  in Thread Title in  
Nick Welburn11/03/2022 15:38:51
128 forum posts

I’ve got a few finished castings that have been mirror finished and now show traces of corrosion. The light stuff is coming off with autosol and a jay cloth.

What’s best for the heavier stuff? Steel wool?

bernard towers11/03/2022 16:14:00
618 forum posts
109 photos

Try garraflex blocks in different grades.

john halfpenny11/03/2022 17:15:46
236 forum posts
24 photos

Scotchbrite pads from your local automotive paint supplier

Ady111/03/2022 17:21:06
5090 forum posts
736 photos

You'll need to protect the exposed metal "instantly" with a film of oil or something, cast iron is very prone to flash rust

David-Clark 111/03/2022 17:31:37
220 forum posts

Years ago I used a cleaning solution from ArcEuroTrade. Wipe it on, leave it a bit and wash of with water.

Neil Lickfold11/03/2022 18:13:05
862 forum posts
195 photos

The corrosion often creates areas that have oxidised and that is effectively metal removed. Unless you take all the surface area down to the minimum of the depth of the corrosion, it will still be there. Garraflex or the rubberised abrasives are good or non flat shapes. On a flat surface, you will need another flat surface to repair it with. If you just want to shine the surface only and are not concerned with it's flatness, using Autosol , but thinned with turps or a very light oil, like plain unscented baby oil, and using soft material like a lens cloth, will restore the finish. But it takes time. Paper towels and even synthetic clothes material will creates scratch marks. Water will make cast iron rust in humid conditions within a few minutes. The other option is to use an oil based diamond polishing compound and soft balsa wood. Using the makers of the diamond thinning agent or baby oil works great too. The balsa will absorb the diamond and then behave like a lap. Lapidary diamond is water based, so I avoid them for cast iron work and other surfaces that corrode very easily. Balsa wood and Autosol also works very well, and you can see and control the area you are polishing. I get a small pack of mixed sizes of balsa wood from the hobby shop and it's about 4 inches to 6 inches long with varying shapes etc. Usually something in there is about right for the job. Keep each piece with the abbrasive type. I don't mix the abbrasive grades.

old mart11/03/2022 18:17:25
3775 forum posts
233 photos
Posted by Ady1 on 11/03/2022 17:21:06:

You'll need to protect the exposed metal "instantly" with a film of oil or something, cast iron is very prone to flash rust

That is true, I used to clean up and deglaze cast iron brake drums in the kitchen sink with fairy liquid and wet and dry. There was an instant covering of light rust in the drums even when rinsed under the hot tap, and the insides of the stainless steel sink would have to be scoured with a brillo pad to remove the CI rusty dust. The rust inside the drums mostly came off simply by rubbing with a rag or tissue paper.

 I would use the Solvol Autosol as recommended already on a polished CI surface, there is no water involved.

Steel wool will help, but is unlikely to result in a polished surface.


Edited By old mart on 11/03/2022 18:20:27

Edited By old mart on 11/03/2022 18:21:53

Nick Hughes12/03/2022 17:59:09
264 forum posts
144 photos

This stuff is good :- Belgom Chromes

I've used this and the Belgom Alu for years on my motorcycles.

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Eccentric Engineering
Eccentric July 5 2018
Rapid RC
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest