Low profile caster adapter for vintage drafting tables

I use vintage US made drafting tables here in my sop for workbenches, cutting tables, and general product assembly. I like them because they are all real wood and thick steel, and the 4 examples I have were made in Michigan, USA. Not wanting to drill and modify the legs to add an easier way to move them around our shop floor for cleaning or adding space, I made up these adapters to fit some low profile casters from Amazon (affiliate link here).

V1 fits well on my newer tables with solid tubular legs, V2 is for the older tables with folded steel legs. (2.45" inner vs 2.38 with a larger corner fold)

Print with 6 walls and at least 25% infill, as the walls will support the weight of the table. The hex pockets are made to fit an M6 nut.  I used some paint on support around the bolt holes and one down the center, as the Core One does a decent job at bridging and the recess for the caster didnt need to look perfect. 

Depending on the table, you might need to add some thin shim material to the sides of the top area to get a tight fit. These fit perfect on my Staedtler tables from the 1950s. 

There is also an included model for wheel adapters, since the wheels I bought were supposed to have roller bearings, and worked poorly on our shop floor, so I printed those (100% concentric infill) to fit some 133x74x27 bearings I had laying round from other printing projects. I did mine from petg, nylon or PC might be a better bet, but with our rubber flooring, these work fine. 

(yes, my files are in inches. scale appropriately)