I have several card scrapers Lie neilsen, Lee Valley, and Woodsmith. I find that all of these scrapers dull after about 9-12 BF of Red Oak. When I say dull the shaving is powdery rather than like that of a hand plane. When I first start with the sharp scraper it cuts great. Whispy shavings beautiful surface. Is this normal? Does a scraper normally dull this quickly? I follow the following proceedure when sharpening:
1: file off old bur
2: Using a jointed piece of wood I hold the scraper 90 degrees to 220 grit sandpaper bonded to glass, then 400, 600 through 2000.
3: between grits I lay the scraper on the sandpaper and remove all burrs from edge to make 90 deg edge.
3: using Veritas adjustable burnisher make 3-4 passes at 0 degrees
4: using same burnisher I set to 7-10 degrees and 3-4 passes with moderate pressure.
The scraper has a uniform burr along the edge. The burr is very small--it just catches the fingernail.
Any help would be great...I have many more shelves to scrape. I need to sharpen tomorrow.