Thanks for the ccompliments.
I been out of town a few days
Jeff, the platform prep I do is to grind the surface good enough to get a coat of powder. The grinding powder helps the tool to get a grip on the square edge surface.
Sometimes if the square edge is not perfectly square the tool will slip no matter what. In that situation I will take real small up ticks to create a spot to seat the tool without slipping. Up ticks that are larger than the area removed by the flake initiation will create a surface angle that is worse than the original angle and will require a larger up tick on the next pass to get a workable angle to seat the tool, so I try to keep the upticks as small as possible for that reason.
I also very lightly nibble the lip off each flake taken before the next flake just to get rid of the lip and space the flakes a hair farther apart.
The main thing I think is to seat the tool then build enough pressure straight in that the flake will detach before the tool slips.
I used to always have small copper marks left where the tool would slip a little before the flake released. That would cause the flake to release closer to the edge than intended, resulting in a thinner flake more likely to step fracture.
I am having a hard time wording this in an understandable way. I'll try to take some pics to show what I'm trying to say this evening. Maybe tomorrow cause I have a fishing team meeting tonight and my nephew brought me some rock back from west Texas that I'm gonna go get after the meeting so I may not have time today.
flungonin, I aint sure what wwould cause short flakes for sure but I think more inward pressure and try to support the piece directly opposite of where the flake is taken, like with a finger against the opposite side to press against. Also if you take some short flakes with a space between them. that creates a ridge to support a longer flake but that can get more complicated than using the ridge left by the previous flake scar. The material may just be to hard too. I've had some gravel that was just to hard to flake and I could only get short flakes from it. Heat treatment should help in that situation.
I'll be BACK!!!