recommend a clear coat spray?

Get clearcoat at any body shop. It's expensive. Bugs

Aerosol lacquer from Home Depot will do a good job as long as the parts are clean. Several thin coats are better than fewer heavy coats.

After some intensive field tests I can say that the best Aerosol solution to clearcoating steel is Rustoleum Clear Enamel.

For Brass and Copper I prefer Parks brand Brass and Copper Clearcoat. It is a lacquer and bonds well.

I disagree about polyurethanes. They do not bond well at all to bare steel. They end up peeling off like celophane tape.

The 2 best finishes I found were Rustoleum clear enamel and a water based acrylic clear coat from a patina dealer I buy from. The rustoleum is much easier to apply and looks better.

When you use the Rustoleum is it the 7701 clear?

What about the clear powder coatings?

Best regards, Spehro Pefhany

Yep that's the stuff.

In the field tests we ran at school it was far superior in rust prevention to all other aerosols.

We cut 8 pieces of 1" square tube, ground them clean and clear coated 7 of them with various products. The eight was left bare for a control. All the tube pieces were hung on our outside chainlink fence that surrounds the welding area. They were left there for 6 months from October to March. In Seattle this is our wettest time period.

The polyurethanes, both water and solvent based, were heavilly spotted with rust. The acrylics were nearly useless. The Lacquers were OK, but still had spots. The Rustoleum Clear Enamel was the cleanest. The water based acrylic primer-sealer from Custom Patina Finishes was the best for protection, but it had clouded over from the UV

Yes powder coating works quite well, but it is difficult to do yourself.