Setting up to grind carbide, on a budget

[Winegrower]

I wanted to get a silicon carbide wheel for carbide grinding and sharpening, wanting a Baldor 12", but not willing to refinance the house for that. So I bought the cheapest Ryobi 6" bench grinder and set it up with a similarly least expensive wheel I could find. Maybe $50 for the grinder, $15 for the wheel, perhaps? And I added a 3M ScotchBrite deburring wheel on the left end, about the same price as the grinder.

But, the tool rest was pathetic and I threw it away. At the same time, I bought a General 825 drill grinding stand, and needed to mount that close to the wheel, on the side, so that took out the wheel guard. I always wear a face shield anyway. When I think of it.

How these projects get more complicated. So I made a tool rest mount by making an aluminum plate to attach around the cast housing of the grinder...it was a slightly tapered housing, so I accomodated that at the mill by boring the hole to the right minor diameter, then using the angled edge of the boring bar to come up from the bottom and cut the proper taper angle...or close enough. Drilled and tapped for a #8 screw and made a cut with a slitting saw to allow tightening the plate on the grinder housing.

Then bandsawed a large chunk of aluminum into a smaller L shape for the tool holder, and returned the smaller chunk to inventory. I love the Jet VBS-900 vertical bandsaw...the sawn surfaces are usable directly in non-critical areas. An adjustment screw, and a relatively large adjustment hole in the plate lets me position the tool rest vertically and in/out as necessary, but I don't think it will need much adjustment. Later, I added a couple 7 degree reference lines for help setting relief and draft angles.

Also, the drill grinding stand fits nicely without interference with the tool rest. I can adjust the tip to wheel spacing if needed for different wheel sizes.

So, I'm happy with this project.

 

[pontiac428]

How is the silicon carbide abrasive working out on tungsten carbide tooling so far?

 

[Winegrower]

How is the silicon carbide abrasive working out on tungsten carbide tooling so far?

My limited experience so far: It seems that silicon carbide grinds tungsten carbide tooling about exactly like a normal grinding wheel does HSS.

 

[Ulma Doctor]

please be careful grinding carbide, it is toxic
i would recommend a respirator and through hygiene after grinding- the dust literally gets everywhere

 

[pontiac428]

It's not the tungsten carbide that's toxic, it's the cobalt binder that makes up the cemented matrix that can eventually get you. In some jurisdictions, it's considered a thoracic particulate, which does not take chemistry into account. In other words, without the cobalt component, it's dust.

 

[Winegrower]

So far, I haven't ground enough carbide to die from it yet, but I appreciate the warnings above. It seems to me that I'm sticking with my original opinion, that the silicon carbide wheel grinds carbide inserts about as well as aluminum oxide wheels grind HSS.

But I did spend some time getting the wheels balanced, which turned out pretty good. I'm adding a thread on that, maybe it will be helpful to others.