Hollow Grind Help

[Jared Minor]

Hello Folks,
I ground a chisel yesterday and I noticed that the hollow doesn't seem to be very deep. It didn't seem to take very long to sharpen it back down to the whole bevel. It could be that I was a little heavy handed on the flat stone when sharpening, and it wasn't a high grit stone by any means. I could tell that I was sharpening correctly because I could see the polish show up in the right places, top of the bevel and tip of chisel. It is a 1/2" chisel. Any ideas? Is this normal?

Thanks

Jared

[george wilson]

I am not sure what you are describing. What was the diameter of the grinding wheel?

I often put a small C clamp on the blade of the chisel I'm grinding,so that the c clamp will be brought up to touch the grinder's tool rest each time I have to remove the chisel to dip it. That way,I get a beautiful,even hollow grind on the blade.

[Wilbur Pan]

Depending on what the diameter of the wheel on your grinder, and the length of the bevel, the hollow can be very shallow. My bet is that what you are seeing is completely normal.

[Jared Minor]

It is an 8" wheel, that is probably why I didn't have much of a hollow. It did make a big difference in sharpening by hand. I definitely think I will skip the honing guide. But I have got to get some better stones.

[Derek Cohen]

Hi Jared

Repeating what I said on WoodNet for the benefit of others ...

I hollow grind on either a 10" Tormek or an 8" dry grinder (1/2 speed plus 3X Norton wheel). The Tormek gets me to the very edge of the bevel. The Norton gets me very close. I would not attempt either if using a dry grinder that threatened to burn the steel.

The closer to the edge of the bevel, the less steel you need to remove with your honing medium (I use a Shapton 1000 to straighten/flatten the edge then a 12000 to hone up the microbevel - all freehanded on the hollow grind).

So the way you grind a hollow can dictate what you have left of a hollow after honing. Even the 10" wheel will leave me a deep hollow because I am removing so little metal when I hone.

Stanley 750:


You lose the hollow too quickly when you remove more steel than you need to do.

Regards from Perth

Derek

[Frank Drew]

Jared,

There's no reason to have too much hollow; you mainly don't want the opposite, a belly in the bevel. In use, perfectly flat is perfectly ok.

[Jared Minor]

Thanks for all the help and the pictures. I guess what I have seen so much has been exaggerated views of this dished bevel. I think once I can get a finer stone, I will be in business.