Summary

The other designs are too big and take 3 hours to print so I designed smaller ones that print in 1 hour. Use 50% infill to make them solid. The hole spacing is 16mm. The 30mm design can be used for edges. The 40mm design is what I am using. I actually buy 3/4" x 3/4" aluminum angle at the hardware store and drill holes in that for the outside edges. I have tried printing edges but they break too easily.