3D Model CNC Machining STL
Many shops are reluctant to machine parts using STL CAD models. Shops that embrace STL have an advantage over those that don't.
I recently surveyed a number of contract manufacturers with CNC machining capabilities. Only one shop responded positively. And they didn't say that they could or did machine from STL, but that they thought they could. I provided them with an STL file of part of an avocado to see if they could tool path it. They sent me a picture of the partial avocado machined from foam. I thought that was a pretty impressive response given that all the other shops either just said "no" or didn't respond.
Why is it important to be able to machine using STL files?
Most additive type rapid prototyping methods (SLA, SLS, FDM, EBM, 3DP, etc.) rely on CAD models in STL format. When going from prototype to production, I think there's an advantage to using the same file for both.
Many 3D laser scanners and X-ray CT scanners output STL files. If the purpose of scanning is to be able to machine a replacement part for a +20 year old aircraft, legacy tooling, patterns, etc, why add the burden of creating solid models from the STL output by the scanners? Why not just machine the STL? The concept is already established in rapid prototyping as "scan to print". If modifications are needed, software like Rapidform's XOR Redesign have tools for modeling with STL.
For more advantages to STL, see Tom Beard's Modern Machine Shop article.
