How can I get SS black finish on parts?

bobgroh · Post by **bobgroh** » Fri Jan 16, 2009 12:00 am

Continuing with cleanup and rehab of my 1994 model 510 and have found some cases where I have blown away the normal Shopsmith black finish, e.g. on the hub and back of the steel sanding disk.

For the time being, I am just going to wax the bejabber's out of the pieces to hold off rust but would sure like to put something back on that is close to the black finish that Shopsmith uses. Now the question: what did SS use for that finish?

I thought, initially, that it was some type of anodize process but it came off way too easily for a chemical process. Seems like it is just paint but it sure is both thin and very defect free for a painting job.

So does anyone know how they do it? And, equally to the point, what suggestions does everyone have on how I can go about approximating the same quality of finish.

P.S. Another example is the jointer drum which needs something.

JPG · Post by **JPG** » Fri Jan 16, 2009 2:30 am

Those blackened steel parts are 'black oxide'. Yes it is thin.

You can try 'gun blueing'.

Keeping it waxed will keep it from rusting if you don't care about appearance.

doug45601 · Post by **doug45601** » Fri Jan 16, 2009 4:26 pm

I've had some great success with a "gun blueing kit".. I redone some hex head bolts after cleanig them real good and mixed up some 'blueing' and soaked them for awhile.. Don't know how well it would work on a larger surface such as a sanding disk.. could get a little expensive I would guess..

reible · Post by **reible** » Fri Jan 16, 2009 6:26 pm

You can buy kits or bottles of stuff to produce your own black oxide finish. I can't remember trade names but if you were to Google "black oxide" my guess is that you will find tons of information on products and kits and how to's.

Ed

reible · Post by **reible** » Fri Jan 16, 2009 6:42 pm

You can buy kits or bottles of stuff to produce your own black oxide finish. I can't remember trade names but if you were to Google "black oxide" my guess is that you will find tons of information on products and kits and how to's.

Ed

davebodner · Post by **davebodner** » Fri Jan 16, 2009 8:13 pm

From http://www.finishing.com...

While most metal finishing processes use toxic chemicals, the black oxide process is especially hazardous, and amateurs are most definitely discouraged from attempting hot blackening! One of the things that makes black oxiding so dangerous is that the black oxide bath operates at about 290 degrees F. Note that this is well above the boiling point of water, and the difference is the biggest problem. Water will evaporate from the black oxide tank rapidly, but when replacement water (which turns to steam at 212 degrees) is introduced, it will have a strong tendency to explosively flash into steam--'erupting' and spraying everything and everyone with this terribly hot and terribly caustic solution. Yes, people have been killed. It is vital that the water make-up system be properly engineered and knowledgeably operated.

Maybe not such a good idea.

Hey, here's a crazy idea. Powdercoating. Expensive, but a wide choice of eye-popping colors. Have the craziest Shopsmith in the state!

reible · Post by **reible** » Fri Jan 16, 2009 9:31 pm

http://www.eastwoodco.com/jump.jsp?item ... ubCat=1485

This is what I'm talking about.

Ed

bobgroh · Post by **bobgroh** » Fri Jan 16, 2009 11:45 pm

OK, no easy answers. I did do a search for 'black oxide finish' and did a bit of reading. Doing the full blown 'hot' black oxide does seem way too dangerous (and probably expensive). The other 'black oxide' treatments (e.g. 'gun bluing') seem more reasonable but may be prohibitive for large surfaces (e.g. for the back of the sanding disk).

Powder coating came up on a ham radio (??) forum a month or so ago and I went out to look that over. A great process, can be done inexpensively (Eastwood has kits) but it is definitely not 'thin' so, in most cases, that knocks it out of contention.

So, for the time being, I'll just stick to elbow grease and lots of waxing afterwards. I did try 'Naval Jelly' on one piece and found it did a dynamite job of removing the existing black! Only a so-so job of removing rust but the black was sure gone!

The Sawdust Session on rust removal gave some helpful hints and places to look so I think I'll buy some more products as my budget allows. Until then, I'll be careful and use lots of wax (the right kind of course).