A remix of the long plate v4 STL from smdollin's "Sturdy Tripod Mounting System for Hadley Telescope" to use ¼" tee nuts instead of heat inserts. I also expanded the #10-24 screw holes to accept the wider pan head screws I had.
See the original model for the rest of the STLs you'll need.
I used these tee nuts: https://www.homedepot.com/p/Everbilt-1-4-in-20-Zinc-Plated-Tee-Nut-4-Pack-802301/204274194
NOTE: Make sure you adjust your slicer settings so it doesn't print in mid air. I have included a .3mf file from Prusa Slicer 2.6 alpha that worked for me. I believe the Expert setting from 2.6 “Extra perimeters on overhangs (Experimental)” helps with this issue.
Default print settings had it print in mid air for me:
My 3mf file gives this improved result:
I printed with 0.6mm nozzle, 100% infill and 4 perimeters. Fits diagonally on a Prusa Mini.
After printing, you'll need to heat up the tee nuts until they are quite hot and heat insert them into the 3 larger recessed holes. Quickly trim any excess plastic that squeezes out before it completely hardens. Be sure to align the cutouts in the tee nut with the holes for the other screws so they have enough clearance:
The author remixed this model.