Coating New steel and oily used steel?

[chromo]

I have some parts I want to coat this week if I get the time. I been tied up since Friday with other stuff. Got 2 systems Friday.

Just to be sure, add any advice you want.

Some parts are new steel that was plasma cut for me. Should I just sand or blast off the gray coating and rust spots, clean with Dawn dish soap, do water break test and spray them and bake. Prebake for out gassing or not?

I have some parts I want to pull from some really nasty greasy engines. Should I do a lye/water bath to degrease, rinse well, blast, acetone or dawn wash, rinse, water break test, preheat to out gas, spray and bake?

Both type parts are steel stuff.

I figured the lye/water to degrease since this stuff has a thick coating of old engine oil grease, I drove the truck today and it lost 2 quarts oil in about 30 miles, but no smoke, so you can guess what the previous owner has built up on this engine before dumping the truck.
So I figure I will drop the parts in a barrel and let soak. And of course all steel or cast iron parts, no aluminum.
What else would be good for this that is not too costly? I'll use the lye now (unless a reason I should not) since I have no more money to buy stuff and it's cheap. I want a 55gal barrel near half full that I can sit the parts in and let soak off the grease, add an air supply tube at bottom to bubble agitate.
Now it's just external parts, later I will want to do the heads and also a engine block in a few weeks or so.

Lye/water will eat aluminum I know. Really what happens is the water breaks down to H2 and O, the hydrogen flows free while the oxygen oxides the aluminum. I make Hydrogen gas this way myself for various things using lye/water mix and drop in scrap aluminum carefully. I get an aluminum oxide sludge in the bottom of the tank, no aluminum left!

What is a good all purpose cleaner safe for steel and aluminum and cheap for 20-30gal?

Anything else I may be forgetting?

For a lye/water degrease I may use well water, for a wash/rinse/breaktest I will use distilled water. I was going to distill a barrel of water but not had time so will buy some.

For a blast media I only have 90grit aluminum oxide, only other things I could get was glass beads or walnut shell and I could only buy one due to low cash.

I stripped a washer shell tonight to make a blast cabinet, I have a couple holes still to patch tomorrow but should work well. I plan to strip a dryer shell to make a spray booth tomorrow if I have time. I have 3 things I will try for small ovens. The new steel parts are only 1/8" flat plate steel 10" dia.
The greasy auto parts will be the size of 2 valve covers or less.

Although I was going to build a custom oven from scratch for larger parts, I found a LARGE stainless steel cabinet today, used restaraunt stuff, and will be picking that up soon as I get the extra $100 and make it an oven later.

[JTW37]

Whew, lot a questions. Anyway, the new stuff, get it good and clean/degrease and media blast, then use simple green to wash it down or I have seen where some have used Dawn dish soap. I like Simple Green. The used parts, you can use brake cleaner or carb cleaner or gas to get off the grease. Then media blast and then Simple Green. The only parts that really need outgassed are any cast parts. Aluminum or steel. Otherwise, clean, media blast, wash, torch it, PC it and bake. Oh yeah, blow off the sand after blasting before cleaning.

Sound like you got the right idea anyway. I just use regular well water and it works okay so far. Oven sounds like a bargain to me. I should be so lucky.

Anyway, good luck.

[chromo]

Thanks,

Well I did some small parts today. Only wanted them coated to prevent rust better than painting, new plain steel stuff. No polishing.
WOW, that aluminum oxide I have really made a dust storm. My cabinet isn't done but thought heck I can use it as is now for a couple small parts. WRONG!! I never made that much dust doing cars in the past!
So I just sanded the parts instead with an electric sander. I needed to knock off rough edges around some drilled holes also.

I washed them in Dawn dish soap before and after sanding, then wiped down with acetone also. Used well water for the washing then distilled water for a final rinse and water break test.

They came out nice considering the steel condition with scratches and dings in the metal.

OK, I'm hooked now even more than before, my first little home built oven worked ok also, so now to finish the blaster cabinet and pull the valve covers from my 4X4 tomorrow
Shucks, I just got the truck and those leaky covers need new gaskets anyways, might as well PC them while off right