As a sort of New Years resolution, I've been working on restoring and otherwise getting into shape some newly acquired as well as old, defunct tools. A lot of my old vintage chisels were kind of ugly, with random pitting scarring the original finishes. Some of them had developed an attractive patina, but others looked kind of leprous. For the latter category, I decided to try rust bluing, in order to get a consistent color and sheen.

In addition to my western chisels I also worked on a few Japanese tools- a couple of new Koyamaichi shinogi-pattern chisels (for chopping dovetail pin sockets) and an old kanna from ebay. The Koyamaichi chisels were not ground to as fine a side land as I'd like, so I ground the sides down to nearly a knife edge. Of course this removed the forge finish from the sides, so I decided to rust blue these as well.

Rust bluing is a conceptually simple process- clean and finish the steel to as fine a finish as you desire, carefully degrease, then cause the steel to rust as evenly as possible. Then immerse the item in boiling water until the red rust converts into black oxide (magnetite). Gently remove any loose oxide with a fine wire brush or steel wool, then rust again and repeat the rest of the process. After several (up to a dozen or more) iterations, a deep jet black finish can be attained. This was the traditional finish for firearms prior to modern hot bluing, and the black oxide finish produced is very tough and corrosion resistant (certainly better than cold blue, and is said to be tougher than hot blue, if not as capable of a glossy finish- it is usually more of a satin or matte).

The rusting process is enhanced by wiping the parts down with a corrosive solution. There are commercial products sold (Pilkington's seems to be popular with gunsmiths), but none were locally available. As this idea more or less occurred to me on a whim, I didn't want to want to wait for shipping and decided to try a recommended home-brew solution consisting of hydrogen peroxide, vinegar, and table salt.

I'm fairly happy with the results, though none are quite perfect:
2017-01-23.jpg
The chisel fourth from the left is a bit lighter than the rest because I tried buffing with pumice, for some reason. Not recommended.


There is quite a bit of information out there, however almost all of it is for firearms. Specific to woodworking tools, Stanley Covington here on Sawmill Creek has several old posts describing the topic. Another source, which is I most closely followed, is from the My Peculiar Nature Blog: http://mypeculiarnature.blogspot.com...-in-black.html


I lost count of the exact number of iterations I used, but I would guess around 10. Using the quick bluing process from the link above, all the rounds could be done in one full day. It is mostly waiting for things to boil and dry.


In addition to the bluing, I made new handles for the western chisels, to replace old ones which were either too short or too ugly. They are simple tapered octagons with whittled socket tenons, of white oak and red oak.