Pipe bending arc for MLA-30+ antenna

Parameters:

• 0.2 mm layer height
• 0.4 mm nozzle/line width
• ~20% infill (not critical)
• Any rigid material
• Prints flat with no supports (45-deg overhang)

For those who wish to replace the MLA-30+ shortwave antenna loop wire with a section of 1/4" (6.35mm) outer diameter stiff copper tubing. This is a very simple hand tool to aid shaping the tubing into a ~26.5' (673mm) diameter circle.

Added finger holes to reduce material and aid with grip. Designed for shaping the tubing as it all lies on a flat surface. It includes a 3-point contact groove in the arc side to guide the tubing and is specifically designed for 1/4" copper tubing, commonly available in hardware stores for refrigeration. 

The 26.5' diameter is designed to be the loop diameter to the tubing center (accounted for tube diameter). Practically there's room to adjust due to the flexibility of the tubing. 

It takes good grip force to shape the tubing, but got me quite close on the first try after a couple trips around the loop while lying on a flat surface, moving the tool one half of its length at a time.

Remember to leave extra tubing on the ends to form contact with the MLA-30+ LNA box! I marked off one full turn before bending the ends down 90 degrees for the LNA leaving a few inches extra on both sides, then flattened the tube ends and marked the nearest location to drill out for the contact holes.

Designed to print with 0.2mm layer height and 0.4 mm nozzle/line width. Obviously not a super dimension or material critical part due to the flexibility of the copper. Printed here with whatever PLA I already had loaded, and used 20% infill.