Main Discussion Area > Flintknapping

knapping precut slabs

(1/4) > >>

Dh88:
Anyone have tips or a video on knappping slabs? I have some novaculite slabs and I can make sharp functional points from them but they always have a pile of little hinge fractures.aggravated would be an understatment

bubby:
I work lots of slabs, use a handpad with a groove in it, abrade the edges good and push in then down, an ishi stick will help to get the flats off, work around one whole side and check after each flake

Dh88:
I have no trouble clearing the face on the first pass.my troulbe starts when im trying to develop convexity on the following passes. Thats when the little hinges start to show up

Jodocus:
I had the same problem and it took me quite a while to solve on my own, a teacher would cetainly have pointed me to the solution more quickly. I'm not sure if this is also your problem, but it sounds like.

In my case, the problem was that the angle on my bevel was too steep (sharp). When raising the bevel, I now try getting somewhat in the 70 degrees range. I lay the bicafe flat on the leather and essentialy push straight down along the edge. After, abrade well.

The reason for having an overly steep angle was mainly reluctance to give up width. Dullening the angle of the edge seems like a step backwards, but it is not. A sharp edge isonly produced when i finish the shape and sharpen the edge in a last pass.

Hope this helps.

Ghost Knapper:
Do you have any pictures that you could share to show how they are turning out? One thing that helps to cut down on hinges with percussion slabs is removing the square edge first and taking short flakes in the beginning and work in towards clearing the whole face rather than clearing it on the first pass, also as Jodocus stated having a proper platform angle really helps.

Navigation

[0] Message Index

[#] Next page