Hand Tools Archive
Rob Lee
Hi David -
Been following *most* of the thread on unicorning (great name)….and have a question/observation.
Double-bevelling (back, front, rounding etc) creates a completely different set of forces on a cutting edge - and I have not seen (or missed) any discussion about that. The intersection of the back and bevel of a chisel blade (sharpened normally) creates a wedge where there are unbalances forces at the cutting edge that are not in line with the axis of application (this would be so much easier to draw....).
My view is that much of the durability is coming from a more balanced set of forces acting both sides of the edge - which is conceptually more compressive forces …..and far less shear. Material just tends to stay put - and not bend or fracture.
Your views?
FYI - my sharpening regimen has always been to back bevel through stropping (AKA ruler trick) using our green compound on pine (I don't like most leather). 800x, 4000x-6000x, then compound....
Cheers -
Rob
Messages In This Thread
- Question for David
- because I mentioned 25 degrees to rob
- separate comment...
- Double-beveling
- will consult Mechanical Engineer neighbor
- Compressive force + Compact edge
- Double bevels...
- Re: Double bevels...
- Re: Double bevels...
- addressing the flat bevel equivalence
- Re: tip geometry *LINK*
- Re: Double bevels...
- we have pictures of bevel profiles. *PIC*
- addressing the flat bevel equivalence
- Summary of response. Hypothesis disproven
- Re: Double bevels...
- Must be a regional thang...
- separate comment...
- because I mentioned 25 degrees to rob