Here's a different take. The Original Parker Process calls for an initial etch, a five minute one with battery acid. I do this. After the etch the barrels are rinsed well, dried, and gone over with 0000 degreased steel wool. Then you apply the first rusting coat. The pattern is very vivid after the etch, the 0000 steel wool does not remove it. I like this as the pattern is visible during the subsequent rustings, so it can be managed better to avoid faults. I also use a Copper Sulphate/Ferrous Sulphate/Logwood treatment (as per the Parker Process) for the intermediate etch, and Ferric Chloride (4%) for subsequent ones.
