Turning Archive 2007
Doug Thompson near Cleveland
>A week and a half ago we talked about grinding wheels and problems with different grade wheels.
Jerry Hall posted a web site sharpeningsupplies.com I called and ordered a 46 and 80 grit wheel, the 80 grit wheel is backordered but the 46 grit wheel arrived in two days. This is the page it was ordered from.
The wheel is a Norton 3X SG "K" grade. Most SG wheels sold in catalogs are the softer "I" grade, I do own a set from Packard and they do sharpen tools very well with no heat buildup. The only problem with a "I" grade is it's easy to wear a groove in the face of the wheel.
Using the "K" grade wheel;
The first thing you will notice is how hard the wheel is compared to a white, pink or "I" grade grinding wheel you had on the grinder before. It doesn't remove steel quite as fast as the other wheels so it's easy to control how much steel you remove, (this is a strong point) The wheel can be dressed using a diamond for a smooth finish or get this... a star wheel dresser for a rough wheel finish. It's hard to put a groove in the wheel.
The wheel run today is 46 grit, this grit should NOT be use for every day grinding because it's just to course. This is however a good example how the "K" grade wears, after grinding 20 tools you can see a concave wear pattern. This is on a slow speed grinder, tomorrow I'll order another Wolverine jig then move this wheel to a high speed grinder. When the 80 grit wheel arrives I'll let you know.