Tetrahedra pics in ABPW

I just posted pictures of the two tetrahedra that have been discussed in the "Woodworking Geometry Question" thread over the last few days.

Once I figured out the trigonometry, it took about half an hour to actually make the second one. They are 18" on a side, scrap white pine.

Scott

Reply to
Elrond Hubbard
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That brings back memories. Many years ago I was asked to make a number of wooden pyramids out of 2 X 2 stock. I just got an ancient radial arm saw and stupidly said I would do it.

I had never cut a compound angle in my life. I did not know the math. I just knew the top and bottom angle. So I set up my T bevel to the angle I was trying to cut. Then I just went at it and cut them every way I could think of. Total trial and error. I figured if I went at it long enough, I could come up with a solution. I filled up three boxes with my little angled blocks. This went on for a week.

Then one night as I was going to bed, I got a clear picture of how to set up the saw. I threw on my bathrobe, ran down to the basement and cut the angle perfectly. I went to bed, got up the next day and cut all the angles. I then drilled the holes and finished the pyramids and delivered them to a (I am not kidding) pyramid shop. (It did not last long.)

The great revelation?? I got a picture of how the saw would see it. A horizontal perspective. I was trying to calculate everything by looking down on the wood. A vertical perspective. When I squatted down and looked at it across the table, directly at the blade, it all started to make sense. My original approach/perspective was 90 degrees off!

To this day, if I have any trouble figuring out a cut, I still squat down and look directly at the blade and figure the cut out from there. It ain't high math or engineering. But it gets the job done. My farmboy approach. Totally different than what happened on this forum this week. Ahhhhhh........, progress.

Lee Michaels

Reply to
Lee Michaels

SBC silently stopped carrying the alt.binaries groups. If you think to, please post a pic to one of the woodworker sites. I cut three of them by hand to see if they fit. Now that that's done, I think I'll carve a fourth and use them for tent pegs, not having a need for a tetrahedron at the moment. But then, I don't have a tent, either. ;) It was fun; thanks for the puzzle.

Reply to
MikeWhy

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other pics show another kind other woodworking I do for my day job.

Reply to
Elrond Hubbard

"MikeWhy" wrote in news:gNoTk.404$ snipped-for-privacy@flpi144.ffdc.sbc.com:

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other pics show another kind other woodworking I do for my day job.

Scott

Reply to
Elrond Hubbard

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