If you're looking to protect metal prior to painting there are probably better products that are actually an aid to painting and not necessary to remove like you would an oil
Picklex is one http://www.picklex20.com/

Grigg



1951 GMC 250 in the Project Journals
1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-