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Med-Hot Black Oxide

I am interested in clearing up some details about blackening. Any help in the following two questions would be greatly appreciated.

We currently use a room-temp. black. Throughout the ten years of use, many of our customers have been dis-satisfied with the corrosion protection it offers. We have avoided hot-black because of the dangers involved. Recently we(engineering) proposed a new solution, an new system that supposedly uses alkaline technology. It is a med-hot (190-200F) black oxide. In our lab testing it has proved to be significantly better in inhibiting corrosion. Are any of you familiar with this process, and is it as good as hot black?

I also have a question about the possibility of masking during the blackening process. We are a clutch and brake manufacturer, and through lab testing have decided not to have the blackening process done to our friction interfaces. This causes us to go to a secondary machining process after blackening. Is there a way to mask this surface with a tape or adhesive, so we can do all the machining first, and then blacken?

Kevin Weiss
- Vadnais Heights, MN, USA
2000

I have seen the new "195 black" and it looks quite impressive. I do not have extensive field experience with same but can tell you its quickly gaining popularity with end users. Masking ; I ran a hot black years ago , flat surfaces that stick do not coat really , , but do fringe coat. Masking may be an answer , but with what?

Ron Landrette
plating equipment supplier - Bristol, Connecticut
2000

Hi Mr. K. Weis! We are a brazilian company and we would like to prove this new med-hot black oxide process. Could you please inform us where we can get it? Thanks in advance for your assistance Ricardo Bastos

Ricardo Bastos
- Diadema, SP , BRAZIL
2000

As far as masking is concerned, I have been experimenting with grease. I am a hot black operator and know too well how grease will prevent the black from coating. Some of the larger parts I run have to be done half at a time. This will leave a brown stripe where the part touches the mud layer at the surface. Using grease to protect the already blackened part, I have almost eliminated this stripe. I use standard bearing grease. But I think something a little lighter might work better. Good luck, I look forward to hearing about your results. Aaron

Aaron Talcott
- Willoughby, Ohio USA
2003