The issue with 3d printing is that nothing is normal Printer to Printer. While @NotFastEnuf has done some incredible modeling work, he will have also made considerations in the design to compensate for the shortcomings of the machine he is working with.
My 3d printer is a CTC Bizer Frankenstein, I cannot believe what its capable of when its dialed in. I get some epic prints. However when I design something in 3d there are a bunch of factors that effect dimensions which are directly related to the limitations of the machine style (Replicator), the nozzle I have installed(.4mm), and the filament that will be used(how steep a slope you can reliably deposite).
IRL, I work with lasers cutting metal. In CNC tools that remove material there is a term ‘kerf’ which is width of the material removed with one pass of the tool from the work piece. You can measure the kerf, of a blade through wood, or a 3kw fiber laser through 3/4" mild steel, and on their respective controllers adjust the “kerf offset” to ensure you are creating a properly dimensioned and Toleranced part. In 3d Printing, which is usually deposition, there is no kerf. Which results in the need to design to the tolerances of your printer.
My bet is that whatever machine the local shop is running is nothing like a home brew 3d printer(or off the shelf FDM).
I recently Had some Experimental pro prints done from our sister company Radical Parts(Thanks Y’all). They turned out beautifully, but the material composition leaves the frame more brittle than a PLA print. What kind of material did the local shop set you up with? Screw holes in FDM 3D prints are not really toleranced. You might ask if the shop is willing to work with you and get you a 100.5% sized print(or calculate difference of the hole and see how much
it is off, they may have a tolerance gurantee)? Slightly larger Might make it less of a hassle to get motors mounted and your mount hole spacing will not be affected much.
Pro prints of the boss 8.5 qx70 V1:
Attempted flexing the frame across the motor axis and the material popped, a piece shattered off of a “duct fin,” I don’t know what to call that as a feature.
They sure are smooth though, and heavy. Compared to nylon at 4.4grams, these fattys weigh 7g even
The Printer that produced these is best described as a big 4 jet ink printer. It uses wiper to even each layer, and a UV Bulb to solidify each layer. Subesquently, infill is always 100%.