Based on an article by James Thompson I found on OldToolsShop.com. I though I woud try using Citric Acid for rust removal. The article can be found at the following link.
Citric acid is used in food processing and seems to do a good job removing rust. I checked the local yellow pages and found a local beer home brewing store. I called them and confirmed that I could purchase citric acid for $5 per pound. I made a quick run over and purchased 2 pounds. I also located a plastic container, a brass brush and some scotch bright.
I had purchased a #5 parts plane for it’s handles at the flea market a couple of weeks ago for $3 and had retained the handles and the frog. The body was badly pitted and had already gone in the trash. From a hindsight perspective, I would have like to have held on to it to use to try it this rust removal technique.
Here is a photographs of the parts before taking the bath.
I mixed up the solution using a mix of 1 cup of citric acid to one gallon of water. I placed the parts in and then came back and scrubbed them every 30 minutes or so. The total time in the solution was about 2 hours.
Here is what they looked like once they came out…
After removing, them I dried them with paper towels, compressed air, and coated them in a light coat of 3 in 1 Oil. I belive it removed the bluing from the metal piece that controls the position of the frog and because of this, I would not use this method for this part or for chip breakers if you care about maintaining the original finish.
Also, another technique I tried from Michael Dunbar’s book Restoring, Tuning, and Using classic woodworking tools was to soak weather worn knobs in Boiled Linseed Oil. This worked very well. Basically you stand the parts in a coffee can with an inch or so of BLO in the bottom and you let it wick up into the parts. 45 minutes on each end.
-- We must guard our enthusiasm as we would our life - James Krenov