Learned new few lesson this weekend

[cruizer]

In my ongoing journey to find and locate new things to powdercoat and learn on, I obtained a few cast iron pieces from work. I sandblasted, cleaned, degreased, outgassed, and coated them.

When I was done, they were prolly the worst looking pieces I have done to date. They are also the first regular cast pieces I have done to date, as the tools are usually forged.

I found out that using paper towel to clean your parts with degreaser is a bad idea, as bits and pieces break off in the rough surface of the cast. And no matter how hard you try, you can't get it all off. What do you use when cleaning your parts?

I also learned that cast iron seems to retain finger oils, as evident on one of my pieces. I took the part inside to show the girlfriend, and was complaining about a discoleration and apparent uneven coating of a part in specific spots. She sait one of them looked like a thumbprint. Then I grabbed the part, placing my thumb where the "thumbprint" was, and all the other marks lined up with my fingers. So one would be wise, i would assume, to use rubber gloves when working with newly cleaned parts.

I also outgassed these parts at 425 deg for 20 minutes. After coating, I found areas where it looked like a little outgassing was taking place. Cast iron doesn't expand and contract as quickly as aluminum does, so I think I should have outgassed them longer, and possibly at a higher temperature.

That is all for today. The guy at work were very impressed with the parts when I showed them this morning. I told them how bad they were, and they told me they looked better than alotof the stuff they get from the distributors.

Any other suggestion, comments, or recommendations are always welcome.

[Popeye]

You want to off-gas the parts at a higher temp and a longer time than you cure. 425 or 450 at 20 is fine, just cure at 375 or 400.
It's always a good idea not to touch any part once it's been cleaned.
IMHO

[cruizer]

Originally Posted by Popeye

You want to off-gas the parts at a higher temp and a longer time than you cure. 425 or 450 at 20 is fine, just cure at 375 or 400.
It's always a good idea not to touch any part once it's been cleaned.
IMHO

Well i cured at 400 for 20 minutes. And outgassed at 425 for 20 minutes.
As for masking stuff off, do you guys do it before it gets outgassed, or after? I found that my tape shrinks after being heated, so masking it before outgassing is pointless, as I would have to remask after as well, which of course requires the touching of the part.

[sdold]

You could buy a box of cheap latex gloves to use when handling the part after cleaning, I always use a fresh pair each time I handle a part.

[fxstcguy98]

nitril gloves will not leave a residue. Latex and rubber may leave a little on the part. Nitril are dirt cheap at harbor frieght, and at some autoparts stores. Clean the part again after outgassing in case some entrapped oils have escaped.

[sdold]

Good tip, I didn't know that about latex.