Thanks a lot
Deerhunter, I have made a lot of successful flutes.
Even most of these broken points that where laying under the jig had one successful flute on one side.
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Does that count?
Really though, the ratio of points with two good flutes compared to failed flute attempts, sspeshully on the second flute, is not very good. I am learning something new all the time and realizing what causes a lot of the breaks. It takes several breaks for me to pinpoint what the problem is sometimes and sometimes it is obvious what went wrong, but a lot of times it just flat didn't work for no good reason at all.
I reworked my clamp arms last night and tried it out on this heated gravel slab. I kept the flutes short due to the material being heated and inconsistent textures.
Here's the first flute and platform for the second flute.