Well, there is some interest out there in this kind of foolishness, hey? Russ, I'm going on vacation in a few days and will be parking some of my projects for a couple of weeks so "R&D" won't have much to report for awhile.
Just a clarification: so far, I have only EN plated the part of the bearing that contacts the shaft, i.e. the "inside bore." Not any internal parts in contact with the rolling balls. You probably understood that. I'm just going by published literature what the resulting hardness of the EN plate PROBABLY is. That's why the question on phosporus content. I'm convinced, though, from what I've read in the Caswell manual and elsewhere that I better starting passing the water break test or I'm going to be sorry sooner or later. A little additional reading has also convinced me that you're probably right about trying a different formulation of degreaser.
I'm going to order some "SP" and give that a try first because it's supposed to be so gentle. I've got some muriatic acid handy, but I don't want to fool with that stuff around bearings for fear of etching the rolling parts then seeing a premature failure. If the SP doesn't do the job, I'll go with a more caustic cleaner. Apparently from what I've read, there's a vast difference in cleaning compounds needed for different lubricants and probably a stout caustic is a good starting place for steel anyway. We'll see, but I'm going to try the SP first because of it's supposed "gentleness."
I can get accurate measurements of my plating thickness by using a micrometer but I think the hardness will be a little evasive. I've read that it's hard to check the hardness of a plate because the measuring instrument basically just pentetrates the plating and measures the hardness of the surface underneath. I'm thinking of a Rockwell type tester. So for now, I'll just test my parts by throwing them in an engine and see how they work out.
I definitely like your idea about plating a piston for wear resistance. Most of the pistons I replace are worn very uniformly on the skirt and nowhere else. When I get back from vacation I'm going to order some BN for that purpose. I plan to plate a rectangular patch on the thrust surfaces of the piston. Also, I plan on plating the inner bore of some valve guides as well. However, unless it self-destructs before, it should be the end of summer before a teardown and inspection reveals the results.
What I was referring to on the "other" proposed project was this: I've got a transmission shaft (out of a motorcycle) where three of the gears ride on needle bearings that in turn ride directly on the shaft. Something passed throught tranny and left some small dings in both the shaft and gear and you can see a slight imprint of where the needle rollers dinged both. Of course, the gear now turns a little roughly on the shaft so it's no good for racing duty and has been replaced.
Now, I've got access to a small, professional grinding machine that can take the dings out of both the inner bore of the gear and the shaft. See where I'm going with this? Next step, plate both back up to original tolerance of course. This isn't the first time I've run into this little problem. And these parts are made in Austria and the Austrian's are mighty proud of them judging by the price for new stuff I can tell you.This should be about the most severe application you could find for EN and things need to be pretty well perfect for it to work OK, but I think it will based on what I've seen so far. I was just wondering whether EKrome wouldn't probably be a bit harder and tougher than EN in this application. Guess there's one way to find out, huh?
Well, sorry to turn this into a mega-reply but I wanted to spit this out before my vacation. Thanks for your interest and I'll definitely keep you posted as I go along.
By the way, that danged Caswell has got me interested in about 3 or 4 new hobbies all at the same time!!! I'm all enthused about powder coating as well as some of the plating ventures I mentioned.
Best regards,
Ed
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