I've been working on some oak pieces, and ran out of my old steel wool ebonising solution. I was also out of steel wool. I decided to try an experiment - instead of steel wool, I used a magnet to pick up all of the dust/filings at my grinder. I added them to white vinegar, and voila! A clean grinder station, and nice, dark ebonising solution in less than 24 hours. I *think* it was faster to make because the dust was so fine. Anyway, there's my tip: recycle your tool grinding dust into ebonising juice.