Hello Jack

If I understand correctly, you have a project that you are now ready to commercialise. This will require manufacturing of plastic electronics housings and mounting brackets, for which you are considering cnc milling as the manufacturing method.

I would just suggest at this point that this possibly not commercially sound, and that you should consider vacuum forming, injection molding (or other plastic molding process), or closed mold GRP, etc. You may also consider purchasing an existing enclosure from one of a multitude of manufacturers/supplier of cheap enclosures.

CNC milled plastic may be commercially viable for simple flat profiles, or if only small quantities are required, but for example, an electronics enclosure (even a small one) milled from thick stock material has a high degree of material wastage.

Having said that, you may still need a CNC router for assisting to make your prototype vacuum forming molds and/or composites molds, which would typically be made in wood or aluminium. Another option, using your 3D printer, is that you could 3D print molds/patterns for brackets/boxes/etc then take composites molds from the printed models. You can also send 3D printed models of molds to an investment casting foundry and receive back an accurate aluminium or steel casting ready for prep/use as your plastics/composites mold.

I would recommend looking at vacuum forming, as it is quite simple, especially for small parts.

Regards, Jono