PA24,
I also use boiling water.Number of applications depends on the base metal,temp, and humidity; but usually 4-5.With the solution I use, it darkens a day or two after oiling.I couldn't find a soft enough wire wheel to suit me for carding; so I use de-oiled(acetone)steel wool. I also apply the solution with a tuft of de-oiled 0000 steel wool. I learned from my German friend Walter Grass and have always been satisfied with wornout 320 grit.Maybe he didn't go finer because to a gunsmith time is money.He said it was pointless to go finer,because of the biteing action of the soultion. Maybe I will try 600 sometime and see for myself.
Mike
