I'm thinking, if the flat kits for the midhorns come with all the angles cut, they're a bargain. The wood is still damp where I was mopping up glue, I hope I got it all. I was going to miter the edges and actually found a formula to get the angle, but it worked out easier to butt the vertical pieces inside. So far so good.

Bill

And yes, the horn kits have the angles cut.

• http://mathforum.org/library/drmath/view/61296.html

I remember seeing an angle dial on some table saws, but I seem to recall that it is not accurately calibrated. Seems like I was told that you were better off using a more accurate guide if the angle was important. But this is not my field of expertise, so I'll defer that one to the cabinetmakers of the group.

By the way , nice work on the horn, looks cool.

Hey, thanks. They look better in the pictures than in person, but I'm looking forward to hearing them. If I hadn't been so impatient, I'd be ordering the kits now, but it's been interesting so far.

You're right, the angle of the sides would vary on the tractrix. On a straight sided conical the angle should be the same all the way. I was able to cut the verticals along each edge and when I propped up the bottom piece to a reasonable angle I could just set the sides in place and put the top on, and it would sit there like a house of cards. I looked all around and all the edges were flush. Neat. I glued and screwed it together and the next day the tops and bottoms had warped inward about 1/4" at the center. I had to build a little brace with a threaded rod to push them out when I glued the horn to the cabinet pieces. Those kits are sounding better all the time, but I'm learning.

• Closeup of brace