Inexpensive black electroplated finish?

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A. Hi Greg. You might be better economically served by finding a specialty hardware supplier and buying the fasteners you need with the black oxide finish already on them. They will not be expensive. The economic problem you are facing is that such parts are plated or black oxided in bulk (by the tens of thousands per hour), adding very little to the cost of the fastener at time of manufacture; but it is labor intensive (and consequently quite costly) to finish them a few at a time on a rework basis regardless of the specific finish you desired.

It is very unlikely that the original finish is nickel-cadmium, as that is usually reserved for very expensive specialty aircraft components; fasteners from Home Depot are almost surely just zinc plated and chromated.

If you want to do something cheap and easy yourself, I'd lightly sand them to remove most of the chromate, then paint the exposed surfaces black. I think they'll look good. Before attempting acid removal and/or plating we'd need to know the grade because those operations will cause hydrogen embrittlement of hardened steel, turning them into brittle glass (although if they're from Home Depot, they're probably not very high grade. Where are they from / what are they for? -- Best of luck.

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Hi. I have the same sort of questions as Greg. I guess since you do not sell a kit to do this, you did not want to take more than 60 seconds to write a reply. Maybe I am wrong, but you would have been the right person it seems to figure out HOW to do this instead of why not to do this. Any jerk can spray paint their bolts. When we take pride in our engines on motorcycles and cars, building the engines ourselves, the reply you gave sounds like a cop out.

I have gone through so many cars and this one, I wanted to plate the bolts to give a cleaner appearance. I even bought brand new ones from Honda to get plated.

I guess you are right though, if it is hard to do, and I cannot do it perfectly the first time, why even try.

Hi, Peter.

Please ask your own questions rather than bitching that the answer to someone else's question didn't answer yours. I don't think Greg had the same aims as you -- based on his concern about "how expensive it is", that he believes they are cheap Home Depot class bolts (certainly not automotive or motorcycle quality), and that he didn't complain about the answer). I tried to answer Greg's question of why rework was expensive, whereas when things are made in bulk they are cheap; and I told him that specialty fastener stores will have what he wants inexpensively. You're insulting me for answering actual questions rather than the ones you had in mind :-)

We also advised Greg (as he asked), that the plating on Home Depot bolts was zinc, not nickel cadmium. Had he come back and asked how to remove zinc plating and do black oxide as a hobby, we'd have pointed him to the dozens of threads on this site covering that.

Please skip the ad hominem attacks. They make websites sour places to visit; we've been on line since 1989 and credit our longevity primarily to our readers appreciating civility; and it just wastes the readers' time to go on about some "kit" that, true, we don't have but you don't want anyway :-)

If someone can't get hands-on instruction, it takes some reading to learn how to do this kind of stuff. Trial-and-error is fine towards learning how to do it "perfect", but trial and error isn't a good approach to safety when acid dipping or plating hardened bolts which will be embrittled by such experimentation. Sanding off the plating and then using a cold gun bluing may be the best approach for your situation. Good luck.

Regards,

A. Hi Ed. The shoeboxes already have pretty good corrosion resistance by virtue of their G90 galvanized coating, but the mild steel tubing has none.

Some potential choices include electrocoating the tubing, and then powder coating both the tubing and the shoeboxes; or zinc-iron plating and black chromating; or black chrome plating; or possibly salt bath nitriding.

Black oxide is no more rust resistant than the oil or wax which you apply repeatedly, and is not an answer for durable outdoors corrosion resistance. The zinc-iron alloy plating with black chromate conversion coating might be a good answer, and aesthetic, but hot dip galvanizing followed by painting (or powder coating) would offer far more corrosion resistance. Good luck.

Regards,

A. Hi Julie. Black chrome can be formulated and operated in different ways, but some of it looks more like carbon black or fine wrinkle paint ⇦ this on eBay or Amazon [affil links] than chrome; this might be what you are looking for. There is also super dark black electroless nickel plating, the darkness coming from the sponge-like way it deposits, with the holes capturing the light ... but I don't know if this is commercially available or not, and it's surely not cheap.

We'd need more info than just the need for dark black to discuss this deeply.

Regards,

A. Hi Daniel. They can contact you privately. Sorry, we can't recommend suppliers in this forum (huh? why?), but if you explain your application we can help you figure out exactly what finish you need to look for considering the material of the substrate, the environmental conditions, the heat limitations on many finishes, cost, production volume, whether line-of-sight application methods are good enough, galvanic compatibility, etc.

For steel components, black oxide treatment or zinc plating with black chromate are probably the two cheapest approaches, but black oxide has no corrosion resistance and zinc plating doesn't have much.

Luck & Regards,