BK17 - want to re-set bevel questions

[tuffluv]

BK17 factory bevel angle is 40 degrees inclusive. I want to reduce this to 30 degrees inclusive.

Got a question though:

1. Becker database lists the grind shape as a "flat grind". If you agree, would the 40 degree bevel then be considered a micro-bevel?

 

[TravisH]

1. Yep.


But, when you reprofile to 30°, the original factory bevel will be removed, so you'll have to add a new 40° 'micro bevel' after reprofiling to 30°.

 

[tuffluv]

Maybe I'm confused. The blade isn't sharp enough for me so I want to reduce the factory micro-bevel angle down to 30 degrees. If I add another 40 degree micro-bevel, wouldn't that get me right back where I started?

The factory flat grind portion of the blade is way less than 40 degrees.

 

[TravisH]

This image illustrates double bevel.

Reprofiling to 30° (AB) thins the edge, removing the shoulder of the original 40° bevel. Then adding back the 40° creates the micro bevel (CD).


"Sharp enough" may have nothing to do with complex bevels. The existing edge may just not be refined enough. If you can't get 'phone book paper' shaving sharp at 40° says more about your skill than edge geometry.

 

[tuffluv]

Let me take a step backwards and ask: Does the BK-17 have a micro-bevel?

Maybe my terminology was off which lead to the confusion.

 

[daizee]

Typically we talk about the 'primary grind', which is the 'flat grind' part, that goes halfway up the blade (in the case of the BK-17).
Then there is an 'edge bevel', which is the 40d inclusive shiny area that should cut.
Usually when people speak of a 'micro bevel', it is an *additional* bevel at the edge of that 40d bevel.

Beckers do not ship with a microbevel.

So you could reprofile the edge bevel to 30d. It will be sharper. It will probably also hold up pretty well. If it does NOT hold up well, you could smack a tiny 40d microbevel onto the edge bevel to strengthen the weakest part.

Personally, I would go to 30d inclusive and try it out. The BK-17 also can be very 'sharp' with 40d, but it is not a very 'slicey' blade because the primary grind only goes halfway up the blade. This makes it more of a wedge than the BK-16, for instance.

 

[tuffluv]

Boy that clears things up Daizee. You're spot on: I'd like to re-set the edge bevel to 30d inclusive.