Yes, Yes more on metal finishes...

[Rasch Chronicles]

Hi guys!

I came upon this today:
From J.V. Howe (of Griffin & Howe),
Formula No. 27, a GRAY color on steel is achieved by immersing the work in a heated solution of:
10 gr. (avoir.) Antimony Chlorid
10 gr. gallic acid
400 gr. ferric chlorid
150 cc. distilled water
The first color to appear is pale blue, then darker blues to purple, and finally to gray. If immersed long enough the metal will assume the gray color.The intermediate colors are better produced when the solution is cold. The above is considered one of the "bronzing solutions."

What I find interesting is the last bit, "Bronzing Solutions." So I did a search here, and nothing comes up.

So i go to the Google, and besides a whole lot of scantily clad bikini models, I found the following:

http://chestofbooks.com/reference/Henley-s-20th-Century-Formulas-Recipes-Processes-Vol2/Coloring-Metals.html#.UQoRemerp8E

A whole bunch of interesting formulas whose provenance I haven't checked into. In other words i don't know how historically accurate they might be. But it might be something some of you might be interested in so i thought you all might like it.

Best Regards,
Albert A Rasch
The Rasch Outdoor Chronicles: George Washington, President and Fisherman

[James Rogers]

Try Henley's Formulas for Home and Workshop, 1907, reprints edited by Gardner D Hiscox.Lots of chemical formulas.

[WadePatton]

Machinery' Handbook had (not sure about the latest editions) numerous formulas for coloring metals.

Yes, kinda.  I have the 23rd edition (1990) and it mostly speaks to the function and purpose of conversion coatings.  I see a formulae for copper alloys but only general information as to black oxide and phosphating steel alloys.

So, as useful as the Handbook is, don't buy one for browning, bluing, bronzing, type information.  But you should have one-even if all your machining is done with a drill and a file.

[keweenaw]

One needs to remember in looking at any of these old recipes, the Howe one dating from the early 1930s, that people weren't so concerned about toxicity, etc.  The MSDS for Antimony trichloride is the following:
Potential Acute Health Effects:
Very hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, of inhalation. Hazardous in case of skin contact (corrosive), of eye contact (corrosive). Slightly hazardous in case of skin contact (permeator). The amount of tissue damage depends on length of contact. Eye contact can result in corneal damage or blindness. Skin contact can produce inflammation and blistering. Inhalation of dust will produce irritation to gastro-intestinal or respiratory tract, characterized by
burning, sneezing and coughing. Severe over-exposure can produce lung damage, choking, unconsciousness or death. Inflammation of the eye is characterized by redness, watering, and itching. Skin inflammation is characterized by itching, scaling, reddening, or, occasionally, blistering

Those hatters went mad for a reason, not antimony in that case, but we can now know better.

Tom

[kutter]

There are some very interesting,,if not down right dangerous to handle, mixtures listed in the older gunsmithing manuals.

Many of the chemicals got very difficult to obtain starting in about the mid 70's IIRC.  Where you used to be able to walk in to a 'Scientific Supply' type of business and buy most anything over the counter,,suddenly sales were restricted and the supplys of the good stuff was cut off to 'non-professional' buyers.

The internet has changed that a lot, and you can get for the most part what you may need. But doing some research into what the hazzards are of each may make you second guess yourself.

I admit to exposing myself to more chemical hazzards than I should have in my youth. But,,it was in the book! and I wanted to make the same blue,brown,black,gray as the guys in 180X did.

Even the amount of mercury that was in the rust blue and brown formulas that I used makes me shake my head,,,and I don't always mean because I necessarily want to shake my head.

Just be careful with the obviously toxic stuff.
There's enough other pointy, hot and sharp things in this business/hobby to damage you w/o looking for more.

Sorry if it sounds like a sermon but I'd hate to see anyone that loves to do this work as much as I do have their shop time cut short because of exposure to this stuff.

[cmac]

receipe from McDonalds??

[WadePatton]

Well, this really dates me, but I bought my Machinery's Handbook when I started at PSU in '61.  It's the sixteenth edition and has four pages dedicated to coloring metals, including a lengthy paragraph on producing a "gun metal finish".

Anyone looking for that book as reference to anything from trig formulas, gearing and cams, to British Whitworth screw sizes may find an earlier edition on eBay for a reasonable price.

i may have to get a vintage(er) edition then. (yeah, kids these days think '90 was a long time ago) 

i got mine at an auction--for 1 dollar.

my buddy bought the Bridgeport...now if he'd just set the dang thing up!