rethinking the BGM-100

[Ken S]

I am rethinking my ideas on using Tormek jigs with high speed dry grinders. For this discussion, I will include 1725 rpm "low speed" grinders with 3450rpm grinders. My thoughts are also influenced by having a Tormek.

I like the water cooled, dust and spark free Tormek environment. I have tried, with some degree of success to incorporate the faster grinding of higher speed into the Tormek world. The best tool for this is a modified Norton 3X 46 grit grinding wheel. It is not as fast as dry grinding, however, it lowers the extra time to a tolerable level while maintaining the Tormek environment.

Reshaping a turning skew has caused me to take a second look at my forty five year old Craftsman high speed six inch dry grinder. For the record, I would prefer an eight inch 1725rpm Baldor, however, I already have this grinder and two good grinding wheels. One wheel is a six inch 46 grit Norton 3X. It will easily overheat a tool, but removes metal very quickly.

The second wheel is an eight inch 180 grit D-Way CBN wheel. It has worked very well in the past with my T4. I now have a Tormek DWS-200 360 wheel which does essentially the same work on the T4. I can safely remove the guard on one side of my dry grinder to accommodate the eight inch wheel. D-Way owner, Dave Schweitzer, routinely sharpens with an eight inch 3450rpm dry grinder. My grinder is rated at 1/2 horsepower, the same as many new eight inch grinders. D-Way sells a special reducing bushing with an inset for shorter shafts for $13. If I need one, that is certainly reasonable. I will need a half inch reducing bushing inany case.

I have some 3/4" MDF pieces left over from my lathe top and shelf. Two thicknesses will make a substantial base. I presently have  two BGM-100 components. I think I might eventually want to switch to the OWC plate and use the plate with the Oneway Wolverine rig, so I will incorporate that into the base design.


This design is far from ideal. A better design would be a slow speed eight inch grinder with eight inch 46 and 80 grit wheels. However, this set up is for reshaping, not final sharpening.

Thoughts?

Ken

[Ken S]

I removed the 80 grit white wheel and guard from my dry grinder. The half inch shaft has very little support behind the grinding wheel. It is adequate for its intended six inch wheel. I think that trying to mount an eight inch CBN wheel on it would be pushing the limits.

I reassembled everything. I moved the Veritas tool rest to the right side, where the 46 grit wheel is. I can still use the 46 grit wheel for initial reshaping, which was my original intention.

While I was working on it, I replaced the original tunngsten bulb with an LED bulb, which is much brighter. I also dressed the 46 grit wheel. I had forgotten how messy grinding dust from wheel dressing is.   

Although the idea was not as successful as hoped, it was a learning experience.

Ken