Caster foot for NZXT H7 Flow case

My computers live underneath the corner of an L-shaped desk, so I always like to replace their feet with casters to make it easier to access ports, etc.

I printed these in nylon (Taulman3D Alloy 910, black) for strength/impact resistance, but just about anything would probably work (might have to really up the density if you want to try TPU). Normally I'd use a 0.6mm nozzle for a part like this, but there's one thin wall that would have suffered.

The only reason for them to be this tall is the screws that came with the casters are something like 9/16" long (14mm+) and I didn't have 16 of something appropriate and shorter on hand. If you do, adjust the caster screw values in cells C15-C16 in the FreeCAD spreadsheet and it should rework things for you.

Parts required

• A NZXT H7 Flow case – and probably others made by this company; this is just the one I have
• Small swivel casters with mounting holes spaced in a square 20mm on a side. Search Amazon for B09Q38VK55 if you want to see what I got, but they're pretty generic. If your casters are larger or smaller, see cell A15 in the FreeCAD spreadsheet.
• Optional: eight (8) m3 x6mm socket head cap screws. Might work with only 4mm; could go as long as 12mm.

Print preparation

Wash off the glue stick if used for adhesion/separation. You should be able to pop out the supports by pushing in a small hex key or screwdriver from the other side. Only the center hole is required; the others are optional…

Optional: I was a little concerned that the locator pins might shear off (force across the printed layers) if it got bumped. If you have 8x m3 socket head hex screws lying around, you can insert them into the holes for extra strength as shown in the second photo. 4mm and 6mm long SHCSs can be screwed in all the way. Longer screws up to 12mm should work, too, just don't screw them in any farther than shown. The should self-tap; pre-tapping them from the bump side will make it easier. If you don't use screws here, you don't need to remove the supports that cover those holes.

Assembly

I carefully laid the case on its large opaque side (right) to do this. Suit yourself. Remove the bottom filters if it's more convenient.

For each foot: 

• Gently pry the rubber pad about halfway off so you can insert a Philips screwdriver at the center and remove the #6-32 screw.
• Remove the original foot and save if you wish to use them in the future.
• Insert the #6-32 screw into the center hole of the printed foot and push it out toward the side with the locator pins. 
• Align the foot to the case so the little slot is inward, toward the filter, and push it onto the case guided by the locator pins. 
• Tighten the #6-32 screw
• Secure a caster to the foot using provided screws no longer than 9/16" (14.3mm) or you'll hit the case

The mounting plates for the casters are a little bit wider than the foot (even without the taper of the original). I tried to align the casters so they were flush to the outside edge of the foot as shown in the third photograph.

Reinstall the filters and set the case right-side up again. (Cover photo)