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Old 03-18-2007, 12:48 PM
seanc seanc is offline
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Default Re: help getting coverage with irregular part

R.B.
Quote:
I REALLY need to get more tanks because at 40 minutes per batch, it is going to take FOREVER to do it the way I have been.
It doesn't always HAVE to be that long. It all depends on how thick a plate you want, and that is purely current & time dependent.

In this case w/shadowed areas, longer times will be helpful.

Commercial fasteners have very thin plate, .0002-.0004 or so. That's what's nice about DIY, you can plate as thick as you want, and end up w/a part that's better than new!

Quote:
I am using a non-caswell acid salt dip, and I was wondering it that was something unique to that chemical.
I forgot to ask about that yesterday, but am curious. What exactly are you using? "acid salt" can be any one of many different concoctions. And what concentration (% wise)?

All you need is a pure acid, appropriately diluted. Nitric is best, but difficult & expensive to obtain. Muriatic is second best, available at any local hardware store as "concrete cleaner" (muriatic is pre-diluted hydrochloric acid, about 30% solution). Only sulphuric should be used before black chromate.

OTOH, yellow chromate already has a significant acid content, and is "self-brightening". You don't really need a pre-dip.

Sean
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