Caswell Stainless Steel Blackening Gel

t1mpani

t1mpani

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Howdy y'all...this isn't a question but is instead an information drop, because I looked up "blackening stainless steel" here a while back and found some ideas and some frustration. Sorry for the cross-forum link routine but I don't want to eat up BF space by posting pictures twice. Anyway, a $20 4 ounce gel kit is available from Caswell and I'm rather impressed with the stuff. This is not their stuff for regular steel etching, this is purely aimed at stainless.

I mention within my post about it that proper surface prep will yield much better results than what I did on that folder clip (and that's not a guess, I've already done it on some scrap 416 that was laying around) but for no surface prep at all and a total of two minutes of waiting, I was pretty impressed to see stainless steel turn black so fast.

Just thought some of you far more talented metal finishers here might be interested in it. :)

http://www.bladeforums.com/forums/showthread.php/837365-Custom-JYD-clip?p=9625989#post9625989

Warren
 
I looked through old posts but didn't find anyone. Actually, somebody mentioned the non-stainless etchant solution from Caswell in one of the threads, which is what I'd gone looking for and then found this stuff.
 
I don't have a use for it yet, but that's the kind of thing I appreciate hearing about. I plan to add stainless to my arsenal this year so I've been stockpiling this kind of info.
 
Warren
i have not used the "Caswell" stuff but was pleasantly suprised to try "Nickle Black" from grobet . it worked pretty good turning most stainless black i never played with it in great detail . i gave a bottle of it to a friend who is a maker he used it on "Thomas" stainless damascus with great results
 
I'm looking for it on the Grobet site, Matt---is it "Vigor® Nickel" by any chance?
Warren
 
Ahah! The Caswell stuff is mercifully nearly free of smell. Really, my main interest in it is to be able to touch up the blackened stainless parts on a few guns of mine that, with carry, have gotten a little worn over the years. I was more willing to try it on a knife clip at first, though. :D
 
Warren
you might want to check Brownells or Midway.. i dont know of anything that can color stainless that doesn't smell like rotten eggs.. the good news is after you use it let it dry overnight ,lightly buff with a cloth there is no smell .. good luck if you find something that works well and is very durable please let me know !! this is all i got ..
 
So far this stuff (Caswell) seems pretty tough, and it took exactly two minutes to do its work. :)
 
Hi, has anyone had any luck using Caswell's stainless steel blackener on hardened 400 series (410) stainless? I have tried for quite a while but the blackness seems to rinse off. So far I have soaked the blade in degreaser for a week, mineral spirits for another, rubbing alcohol, and have even placed it in a detergent/steam cleaner for a few days. I've also tried cleaning with a commercial surface prep solution for painting stainless steel, physically scraped the surface with a stainless steel razor, and soaked in muriatic acid. Still no luck... Thanks,
John
 
Hi there,
(I'm still subscribed to this thread). Well, stainless being stainless, the actual bond strength between the steel and its oxide layer is even weaker than the one that "cold blue", acid etchings, etc. get on regular steel. On any of them, though, the key is exposing new material and immediately hitting it with the chemical blackener before the surface reacts to anything else. Too high of a polish will yield a lighter colored, uneven, and more fragile finish. In general, if I'm trying to blacken with any of the wipe-on chemicals, I degrease the surface (this can be done quickly, no need for having it sit for days), sand the surface no higher than a very even 220 grit (using a new, dry piece of sandpaper so as to not smear any dust or oil from another project onto the steel) and immediately apply the blackener with a clean piece of undyed cotton, rubbing it in for about a minute. The directions on the caswell say to deactivate the stuff with water after a few minutes, but I usually just soak it with oil and let it sit for 20-30 minutes, during which time the oxidation seems to "cure" and get a little darker. The "sealant" they provide is basically clear nail polish and I don't use it.

I've blackened plenty of 300-series stainless, some ATS-34, VG-10 and S30V but haven't taken a swing at 410. Tell us how it goes!

Edit to add: you can also try adding heat to the equation right in between the sanding and chemical application steps, using either a torch (briefly), a heat gun or even a hair dryer. I haven't found it to be as beneficial with stainless, but it certainly doesn't hurt.
 
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I've been trying to sign up at a file sharing web site so that I could post a picture of what I'm working on, but haven't had any luck yet (grrrr). Basically, I only want to blacken the background of an engraving, so there is no way to sand. I would think that scratching the surface with the razor blade would have done essentially the same thing though.

Once I do the surface prep, I immediately try the gel. I soaked with degreaser etc for long times because I was laboring under the assumption that either oil from the heat treatment/quench&temper or wax/rubber from polishing had gotten into the metal's microscopic pores. But applying some gel onto the cut edge of the stock steel that the balde was machined from resulted in it rinsing off the same way. Then I tried leaving it on for 20 minutes and it didn't rinse off! Maybe you are on to something there!! Can you give me more details about the oil you mentioned placing on it? The gel is water based and so I place my work piece in a plastic container with a paper towel that has been soaked in hot water so that the water in the gel can't evaporate... Thanks again! John
 
There probably is an oil that would be better, but I've always just used food-grade mineral oil, as it is pretty much innocuous to any other material it might come in contact with. The point, as I understand it, is to "drown" the oxidation process once it has reached a certain point. One caveat, if I've ever gotten any kind of oxidation catalyst (caswell or anything else) into an area with really tight little crevices or seams that I can't effectively clean, I usually use krioil or some other super-thin penetrating oil, in the hopes that their excellent capillary action will dilute-diffuse any leftover chemical before it can create actual corrosive damage.
 
gunengraver said:
Rustoleum flat black thinned out and applied in several layers as needed and you're good to go that's one thing us engravers use
Click to expand...

Sounds like a great alternative as the 410 doesn't seem to be cooperating--and welcome to Bladeforums!
 
Thanks t1mpani and gunengraver for the suggestions, I'll definitely try them out! I was actually thinking about using some sort of a paint given the problems I've had with clear coating the handles after their engravings were blackened (304 stainless polished to a mirrored finish). The clear coat enamel tends to either contain little bubbles from humidity in the air or dust and then chips off the edges, drips, etc.

John
 
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