rust remover is better than convertor. The 3M product sucks balls pls dont waste your
money on this scum company that uses less phosphoric acid than the others.
At best would be to buy the industrial phosphoric acid its supposedly awesome.
Anything under 34% phosphoric acid is not worth it.
Some people recommend Naval Gelly in several applications. Ive found letting the
solution sit till it turns black then scrubbing it again with fresh solution with
a small wire brush or sand paper and watch the rust separate from the metal and
dissolve away.