one of my thinnest preforms.

[iowabow]

Well I spent a good part of the day breaking biface after biface chasing a rabbit. I hit a certain kind of platform with my antler bopper and had an interesting thought so I used a bunch of chert chasing a rabbit and finally I kinda thinned about as good as my copper. Never thought it would happen but we'll here it is. With steps and all. I was inspired on this one by a marty rueter video where he said I need to really push my skills.

[mullet]

Man, that is thin, John. Hope it's not a "secret".

[nclonghunter]

Sometimes I will get a preform that looks good but there will be one spot that is too thick or an odd look to it and doesn't fit the rest of the point. I now look at it and decide if I leave it I will never be happy with it, so I decide an avenue of attack and go for it. Used to think breaking them seemed worse than leaving it, but I guess I have gotten used to breaking them...lol

Hopefully you will show us some of the thinning method you learned. That biface looks really thin and wide. Well done! Way to push the learning process. You got a pile of debitage in the background..LOL

[iowabow]

No secrets just have to eat dinner first

[iowabow]

Ok so I was going to smack this platform that was really to great an angle and it was on the base. With the platform so steep I tilted it to about a 45 degree angle. And gave a good hit.  I never hit a stone like that way unless I want a step. In this case I was trying to step it because it is a fast way for me to hit a stone three times and get some good reduction but that's another story. There happened to be a ridge so everything was there except an unusual choice for where to hit the platform. I hit it very slightly above center and it cut the stone in half and wow I sat back and thought crap I have been doing it wrong for three years. See I do a fine job up to a point and then I can't reduce the stone anymore. I never could figure out why but now I know why. I was trying too hard and being much to careful.  It is so much easier than I thought. I wrote many post about platform preparation and break flakes and so on and so on....well it is so much easier.

[iowabow]

So I also made this one and I want you to notice the flake on the tip. I included a close up of the platform. Notice it is  3/32 thick and I built a small platform with that steep angle. I gave it a hit and then I knew this was the ticket. The reason is because now I know more certainly than ever that I should be able to thin very thin preform using this technique. 

[iowabow]

That preform broken in half because I hit that third ridge on the right just too high on the platform. But I know that you can get 3 passes from one set up. But I made sure to move the deltas in just a bit. In the past I would reduce them to a single ridge. This now seems to be a bad idea.

[nclonghunter]

You are holding it at a 45 towards the ceiling or the floor?
As odd as it sounds when using a billet I tend to hold the preform at a 45 towards the ceiling, however with punch work it is lower. Hitting high and low with a billet is why I am working the indirect percussion now. The accuracy is a lot better.

Thanks for the post and pictures. Really like those wide flake scars.

[iowabow]

Kind of like this and tonight when I get home I will make a couple platforms to explain that better as well. Man if the platform is not just so it won't work. The margin is narrow but not impossible for the average knapper. But be warned you a riding on the edge of stepville.

[iowabow]

If you do step it you know you are close

[iowabow]

We all should be able to knap as thin as where my fingers are on the preform. This is not hard guys it just runs against the safe way bifacing works. It is that place when you are making a point that no longer wants to thin so you try so hard to concentrate so you don't screw it up and you think it if I just have the platform sticking out and I barely hit I can take a nice thinning flake and not ruin this gem" ok trash that idea. Then get more aggressive on the platform angles and hit it higher than you think with a steeper angle than you think. These are all the no no rules in my abo book. I have now torn those pages out and rewriting the game plan.

[iowabow]

Never thought I would see the light in abo. And as you see I tried to keep thinning it and took a chip with the ishi lol. Ya gotta keep trying right!

[le0n]

But be warned you a riding on the edge of stepville.

i call those 'thinning steps'

Then get more aggressive on the platform angles and hit it higher than you think with a steeper angle than you think.

i wonder if your angles of attack are similar to what i'm experimenting with.

i get the feeling that i'm going to snap the piece in half. at least this would happen if i were to pressure flake with these angles and platforms. but i keep my finger tight against the underside where i want the flake to be.

come to think of it, if you don't strike fast enough, it will probably could snap in half.

[iowabow]

Yes sometimes I support and sometimes I leave room for the flake to run just depends

[iowabow]

Here are a couple platform pictures and the preform from tonight. BTW the hold should be half of 45 degrees so more like 22.5 degrees.