I have to confess that I did pretty good in plane geometry back in H school a long time ago, but didn't go on to solid G. Big regret.
I'm making a pyramid (actuall the top is cut off and it will become a lamp shade...art glass will be framed by my work) I've made four trapezoids that will form the sides of the pyramid. The base and top must, of course, form a square. But, right now the face of each trapezoid is 90* to the edge and I can't glue that.
Here's the problem: Is the bevel angle 45* on the edges? If so, it just doesn't look right. When I clamp an edge of one trapezoid to the face of the adjacent one the angle where they meet is less than 90*
Am I over thinking this or is there something I'm missing?
What's really agravating is that I did one of these a few years ago from plans in a mag. Can't fine the plans and can't remember how I did it! The shade turned out really well. My second attempt is turning into a nightmare
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