A MECHANICAL EXPLANATION of Cushing's historically recorded flintknapping method

[AncientTech]

For those who are interested in authentic points and point types, there are three phases involved in Cushing's under-the-knee flaking method that was in use by the American tribes - INITIATION, RUN, AND TERMINATION.

INITIATION - The initiation is the beginning of the break, at the platform site.

In the method recorded by Cushing, the preform OVERHANGS the edge. Why? Why didn't the American tribes simply "rest" the preform on the support stone? The reason why is because the overhanging of the point induces bending. Why bending? Because the thoughtful knapper knows that he must "cleave" his stone, in order to get it to break. And, the employment of bending, combined with an indirect blow, helps to pull the stone apart.

Now, those who work raw chert probably realize that it is easier to keep a flake running then to get the break to initiate. So, by combining hard bending with indirect shock, the knapper gets the break to START.

RUN - The run is how the break rolls along after it is started. In the method cited by cushing, the padded hammerstone creates a bit of a fulcrum effect, when it has a rounded surface. When a downwards blow - or even pressure - is applied to one edge of the preform, the other edge of the preform presses up, against the leather wrap. So, this can affect the "run" of the break, as opposed to if the preform is simply rested on a flat surface. If less pivot pressure, or force, is induced on account of the stone, the the break may run straighter. But, if more pivot pressure is induced, on account of the curvature of the stone, the upper pressure point against the leather above shifts the location of the support, and the break can be induced to turn.

TERMINATION - The termination is where the break actually ends. In a coast to coast flake, the break would either reach the back edge, or it would cut through the back edge, without turning. In an overshot flake, the break will turn PRIOR to reaching the opposite edge.

So, in using the method cited by Cushing, in 1895, and possibly at other times, the knapper must first put on his "thinking cap", before he takes his shot. How much bending should be in the initiation? How should the flake run - straight or rounded? Where should the break terminate? Beyond learning a "skill set", the knapper must learn to use his brain, and work through various new thought processes in order to organize how his shots will be carried out.

So, there are three aspect to the flaking method - the flake's initiation, its run, and its termination. Each phase is affected by a number of factors, that can be altered by the flint worker.

[aaron]

Thanks for the detailed analysis of this technique.
I agree that the biface (or at least the platform) must bend to initiate the break- this is common to all techniques. the only way to stop it from bending would be for the "anvil" (what ben calls the hammerstone below) to perfectly conform to the shape of the biface- which seems effectively impossible. I think that what this technique does to aid initiation is to clamp the biface very firmly, while leaving some room to bend at the "overhang".
I'm not sure I understand your section about the run of the flake being straighter or more curved by using more or less pressure. I do understand the fulcrum effect you describe, similar to what I say in the paragraph above.
I'm sure that a knapper must put on his thinking cap wether or not he used the cushing technique-and would guess that all techniques have aspects that allow initiation through bending, control run through pressure and cause termination at the desired spot.

[Zuma]

Ben for the record---
Please tell us exactly what Cushing said and and illustrated about OVERSHOT.
Be as specific as you are normally.  Also include his teachings on FLUTING.
Inquiring minds need to know this very important information.
I assume you have already shared this info with your facebook followers.
So please don't keep us in the dark.
Zuma

[AncientTech]

Overshot and fluting?  Cushing??  You missed the boat somehow.  Cushing lived during the 19th century.  He recorded Native American life, including multiple flaking practices.  Overshot and fluting is from the Ice Age.  You must know that, right?

The actual flaking process can be used to make many, many different kinds of flaking, at will, depending on what type of anvil stone is used, and what kind of controls are put into place. 

So, I realized in January of 2015 how the process worked, and how a variation of the process could be controlled to create the overshots.  Then, 20 minutes later, I carried it out.  But, I did not show flintknappers anything except the results for three years, because I found that there is far to much disrespect, and far to much "hero worship", in the flintknapping community.  So, I stuck it to people for three years until I was certain that they would not have a chance to tell another lie and say, "We already knew."

Today, Colby Dixon became the eleventh knapper to learn the overshot technique, and carry it out on the first try, after watching my video.  He went back and looked at a preform that he had collected from a site.  And, I think he went into shock.  He even posted a video showing his work, and the preform.  Colby is a knapper that some people consider to be the best there is.