Thread: Setting the bevel and razor geometry

As a new honer, I'm a bit confused how to approach razors with uneven bevels. I see some using pressure on the blade to create an even bevel. Some work the razor's geometry (adjusting the spine) to get an even bevel. My assumption is that every razor needs to be evaluated individually, but is there a preferred approach to this?

The bevel is a direct relation to the spine and the geometry between the two

BUT

Adding in the "Human Element" and the addition of a third surface (Hone) means that you have four things that are working together when creating that edge..
By adding Honing Gymnastics, judicious use of Tape you can correct many issues that may have been created during previous honing cycles. Just how even you can get it is only limited to the fact that you cannot add steel back to the razor

Use of the MMT magic marker test will help you to assess the edge in the beginning

Thank s for the advice. I actually watched your YouTube video when you used blade pressure to hone a Kamisori with an uneven bevel. Do you ever remove metal from the spine in a bevel set? And what circumstances would lead you to do this?

Originally Posted by Midway

Thank s for the advice. I actually watched your YouTube video when you used blade pressure to hone a Kamisori with an uneven bevel. Do you ever remove metal from the spine in a bevel set? And what circumstances would lead you to do this?

No

The only time I have EVER removed spine metal is if the spine scratches the strop because of a sharp edge protrusion.

Originally Posted by gssixgun

No

The only time I have EVER removed spine metal is if the spine scratches the strop because of a sharp edge protrusion.

Same here, there has to be a drastic reason not to use tape. i learned my lesson very early when i almost wrecked a blade. it's impossible fix once you go to far

Nothing on the spine will ever keep the edge from contacting the hone - and nothing else matters. You can increase bevel angle/reduce bevel width if needed by adding tape, but the evenness of the bevel is dependent upon the surface of the blade. If the surface is uneven/irregular, when you cut a plane through it by honing (the straight line between the spine and the edge) then the bevel will be irregular. Period. The only way to have a geometrically perfect bevel is to have a perfect blade surface in perfect alignment with a perfect edge and perfect spine. Of these elements, the only one that matters is the edge - and it will be made perfect when the bevel is set.

[/soapbox]

Here is an illustration of uneven bevels borrowed from Coticules.be:

Regardless of the bevel being of even width along the blade or varied/wavy width along the blade, so long as the bevels meet all along the blade the razor will shave because the edge is set.

An uneven bevel is mostly a cosmetic issue indicating one or more issues/faults with the blades geometry.

Bob