Black Oxide Plating

I have used the Caswell kit. If you are patient it works fine. It does not dry and set overnight as they say. It takes about a week. Then you still have to wipe it dry. This will wipe off some of the blacking as well as the oil they use to 'fix' it. It will still leave a little 'blacking' on your hands if you handle the part unless you leave it another week and wipe again. Then it seems fine. If you are not in a hurry you end up with good results.

 

Not worth it, except for the odd piece. If you have a lot of pieces, go to an accommodating industrial plater and have real black oxide process. It will be 25 times more durable, much deeper black, and not come off black in your hands, except for the oil, which is essential for longevity. Best to prepare the hardware yourself; degrease, dress or repair as needed, glass bead blast to bare metal and rinse/brush with denatured alchohol to remove residue. The alchohol will absorb any moisture and blow dry quickly. Be sure to inventory.

 

I was under the impression that the commercial black oxide places clean the pieces in some way prior to coating them. It looks as if they either acid dip them or tumble them. I haven't pre-cleaned the parts myself, mostly I guess I'm too lazy to clean dozens of bolts and washers.
Does anyone know the exact process involved in black oxide?
Morris

 

Yes, a commercial place will acid clean the parts. However, if you give the plater a clean, carefully prepared batch of parts, the plater will recognize that you are looking for a nice job and usually will be appreciative and more attentive to your rare items. Also, the time in the acid preparation will be reduced to a minimum. Doing at least some preparation also helps you identify bad threads, etc. True black oxide is done at very high temperature involving steam well above the boiling point, plus the chemicals. It is a hazardous process. As I understand it, cold black is room temperature. The chemicals are a substitute to those used in the hot process and the finish does come off. Google black oxide for more info.

 

John, I just had a local shop on the peninsula do some Black Oxide Plating for me, and the results were fantastic. If you want to coordinate dropping them off, you are welcome to pop by. I did all the pre-cleaning, blasting and polishing (which took for-friggin'-ever), and they did the washing and re-plating. I doubt the parts looked this good when they were put on the car 40 years ago. I cannot imagine a do-it-yourself kit will do the job as effectively.

By the same measure, you could also paint your car yourself as well, but my sense is that such a stunt would also prove to be a mistake - LOL!

 

John I too just came back from the platers with 12 washers and 12 nuts for my Weber carb/manifold done in black oxide. If you have more to do save it up because they usually charge $100 min for a job. CB

 

If you want black oxide, a professional treatment is the way to go- looks better and lasts longer. Having said that, I will go on to say that black oxide is actually a very poor coating even when done professionally. Doesn't last that long at all, especially in a moist climate. For my last restorations, I have used black zinc to replace the coating on parts that were originally black oxide. Black zinc looks nearly identical and lasts much, much longer. Costs very little more for a much better coating, so you might want to consider it.

 

As long as we are on the subject of black oxide, what did you guys decide to do with your brake bolts? I am currently working on my brakes and my research has turned up bolts in both black oxide and white zinc. Mine look like they are black oxide, but that could be from 40 years of being covered in grease and oil.

 

I notice in this photo you are missing your brake pad covers. Are you going to use the ones you purchased or do you have ones that were left off on this photo?

 

Another approach is to take everything apart and do all the pieces you are going to do at once - that way all the re-plated pieces will look to be the same color (this may be what you meant). For example, I'm doing all 4 corners, including brakes, suspension, steering, hubs. Spend $20 and get a bunch of ziploc bags with write-on tabs, and you cant go wrong. The hardest part will be the boredom you will feel while blasting and polishing umpteen identical tiny pieces.

 

Yes. It covers the clamp that is bolted on to the caliper at the left side of your photo. It uses the same bolt and keeps the dirt out (though obviously from my photo, it does not keep out the rust!)
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True gun blue process is very similar to black oxide process, but Ferrari mechanical bolt and fastener hardware 50's and 60's is usually black oxide. Brake caliper saddle mounting bolts for Dunlop brakes usually black oxide. The bolts holding the wheel cylinders to the calipers saddles clear cadmium. In John's photo of rear axle, the Allen head bolts holding wheel cylinders to caliper saddle non-original?

 

Not only are the allen bolts not original I always thought the calipers and the brake housing were cad platted.
Morris

 

I would think that the answer to the original question is gun blackening. That's a process I've only toyed with, but it involves hot oil blackening a steel surface for protection. It's simple, cheap and effective, and (unless a part is aluminum and oxidized) it would seem the most likely treatment that Ferrari would perform.

It's NOT a black oxide deposit. It's actually close to Parkerizing.

I hope this helps,

Matt

 

Researching this, true gun bluing and black oxide are essentially the SAME process, resulting in a conversion of the surface to something called magnetite Fe3O4. The color variations come from the minor variation details of the process and the nature of the metal, but it's the same thing. There are numerous varieties of the cold stuff, most involving a deposit of copper-selenium. Parkerizing is a phosphating process, a conversion coating of zinc phosphate or manganese phosphate, apparently done inthe presence of phosphoric acid. Tends to be more gray or gray green. Black oxide is an industrial process that's been around a long time. Ferrari bought fasteners from outside industrial suppliers like LOBO and it would have been no problem for them to have the process done outside for other parts, as it is a military and automotive industry standard. The advantages are that black oxide adds no dimension to the part, avoids embrittlement, and with the after treatment of oils or wax, offers fair corrosion protection. True gun blue or black oxide is not a home application. It involves furnaces and steaming salt baths of around 290 degrees. I'm no chemist, just read up on this - all kinds of information pops up on the web under black oxide or gun bluing. I've had industrial black oxide done and it comes out nice and deep black, just like a new LOBO bolt. I see no reason to have to polish the parts once you've fine glass bead blasted. Yes, Dunlop brake castings were clear cadmium.

 

The kit from Caswell ( http://www.caswellplating.com/kits/black.htm ) is quite a bit cheaper that the stuff available in my local gun store. Caswell also sells in larger amounts. I haven't used either, but checked it out.

 

great info here.

Can I please request some photos of properly refinished black oxide hardware?