As Bob Ross used to say, “We don't make mistakes, just happy little accidents.”

I was designing these to hold my jack stands on the wall and quickly found out they will hold so much more.  I am still strength testing this prototype seen pictured.  The prototype was printed in eSun PLA+ with only 2 walls and 10% infill in order to get it done fast.  I am pleasantly shocked by how strong it is without using a more appropriate slicer setting.  Without any bending or deformation, it will hold my 6ton jack stands or just as easily my 3 and 4 ton stands as well.  It also holds my shop creeper, 3ft step ladder, welding mask, etc.  I would NOT recommend printing it with these settings, but its great to know that even in its weakest form its still strong enough to hold all that.

Settings I would recommend:

-PLA should be fine, but you may want to go stronger depending on your application

• .2 layer height but this is just to make sure you don't under extrude by accident.  If your printer can lay down enough plastic, the design doesn't rely on layer height.
• Min 3 walls/perimeters
• Min 40% infill
• 6 layers top and bottom…  I do the math out so that the top/bottom and total wall thickness are equal.  if you use .4 lines and 3 walls that's 1.2mm of thickness.  6 layers at .2 layers is 1.2mm.  If you adjust the number of walls or layer thickness, i would still suggest that you try to keep the top/bottom to wall thickness ratio 1:1

I have exported the STL in the correct orientation for easy printing.  You shouldn't need any supports, rafts, brims, etc unless you have warping issues.  By printing it laying on its side, each layer is the entire shape of the holder meaning layer lines wont effect your results, and the forces at play are not pulling on your layer adhesion.

The holes are designed to allow a #8 screw to fit loosely and counter sink perfectly.    As an added happy little accident, the part is the same size as the flat edge of a 2x4.  So if you line it up with an exposed wall stud, the screw holes should self center themselves in the stud for optimal hold.

edit:

My wife has asked me to test these holding school back packs because the simple clean lines fit her decoration style.  I'll report back if they hold that kind of weight.