A bit on how to assemble the pie cuts...

So when you cut straight tubing on an angle, the cut sections oval just a bit (no longer a perfect circle). Therefore, you always want to match a cut angle end with another cut angle end.

When you start the bend coming off a straight piece of tubing, you have to EITHER cut the straight tube on an angle OR add a small segment (wedge) that is cut square on one end and angle cut on the other.

You cannot (or shouldn't) butt the wedges straight onto the end of a tube cut square. They won't match perfectly.

Accordingly, the smallest angle you can make is 2 times the angle cut of your tubing. For example, in my tubing I'm making each cut 4.5 deg. the smallest angle I can make is if I butt two tubes with 4.5deg cuts on the end which equal a 9deg bend. Each wedge I put between the two straight sections add another 9deg. So my choices are 9 (no wedges), 18 (1 wedge), 27 (2 wedges), 36 (3 wedges), 45 (and so on...), 54, 63, 72, 81, 90deg.

When I set the chop saw to cut at 4.5deg, I will always get pieces that if put together result in those angles.

To change the centerline radius or the width of the bend, all I have to do is vary the length of tubing cut as calculated by the excel program I linked earlier. The angle of the cut doesn't change.

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