Thread: Hollow grind or flat bevel for plane blade

Either, take your pick! If your wet grinder is 10” then I would definitely go with the hollow grind, but only because it takes much less physical work than flat abrasives.

I stick with the traditional flat bevel using the same Veritas jig, 25 degree primary and a 30 degree secondary; when the secondary gets to about 1/3 of the total edge then I work on the primary again. The secondary only sees my finest sharpening mediums so keeping it as small as possible means touching up an edge is done quickly.

BU or BD?

Regards from Perth

Derek

I hollow grind then sharpen with the honing guide. That way there is less material to remove with thee water stones.

Bevel down, Derek.. Just an ordinary old Stanley #4 plane

For BD plane blades, I hollow grind at about 25 deg and then hone at a couple of degrees more.

Originally Posted by Dengue

Bevel down, Derek.. Just an ordinary old Stanley #4 plane

Okay then. With BD plane blades and bench chisels (with the exception of Japanese chisels), I hollow grind all at 30 degrees. The purpose of hollow grinding is to reduce the amount of steel that will then be abraded on waterstones. Harder and more abrasion-resistant steels, such as PM-V11, A2, and M2/M4, benefit this way. The reason I choose 30 degrees is that this is a good compromise for most steels for a cutting edge, and I then hone directly on the hollow. The hollow acts as a jig to balance the bevel. This results in what I call a "co-planar micro bevel". It is not a secondary bevel (which, by definition, is a higher angle than the primary bevel). Honing speed is one other benefit. Reproducibility of the bevel angle is another.

The benefit of a honing guide is reproducibility. Reproducibility is the key to speedy sharpening - one does not want to be starting again each time. The honing guide excels in creating a secondary bevel at a specific angle each time (there are jigs to set the angle reliably), and it makes absolutely no difference whether this is on a flat or a hollowed primary bevel.

The aim of all honing on the tougher steels should be to create a micro bevel. In the case of a honing guide, the aim is a secondary micro bevel. I use honing guides for BU plane blades, since the angle of the secondary bevel determines the cutting angle, and the cutting angle is a crucial weapon in controlling tear out with a single iron (no chipbreaker) plane. In the case of BU blades, I continue to hollow grind, but only because this is what I have for grinding. I used to use a belt sander, which created a flat primary bevel, and that was no different. With secondary micro bevels, the amount of steel you remove from a flat- and hollowed primary bevel is the same.

http://www.inthewoodshop.com/Woodwor...gStrategy.html

Regards from Perth

Derek