lamp bracket undermount

The clamp for my swing-arm lamp broke. I found this thing and made it:
https://www.thingiverse.com/thing:21479

but it's only the top. so i made the bottom myself. This one is much beefier than the original. Designed in blender.

Mine was printed out of black ABS. i had some warping on the bottom, so i sanded it flat with 80 grit sandpaper after. I did an acetone vapour bath after to clean up the lines. Both pieces actually got the same treatment (top and bottom). I still had the metal bolt