1. Solidworks for shape cutting is way too much tool for a simple job
2. Steppers work fine for plasma and oxy and have fewer moving parts. Servos are faster with more torque but make sure they have differential drives for noise reduction on the encoders. Work with a vendoe that will give you a choice of either and tell you the pro's and con's of each.
3. Avoid ballscrew in plasma. Way too dirty an environment and lead whip on 8 ft ballscrews will limit rapids to well below the 300 IPM target speeds.
4. THC is essential for production cutting. You are skimming above the surface at 100+ IPM with a gap of .060 or less. Metal warps up and down while being cut. Let the tip touch the metal and your consummable life drops drastically. Consummables account for a major part of the cutting cost.
5. Try to pick a system that lets you pick and choose the three basic parts of CNC: CAD, CAM, Control. If you get boxed into a solution that makes you use their entire system (aka PlasmaCAM) or uses special hardware you cannot source or replace yourself then your flexibility and options are limited.
Look past next week and into the future and determine if your needs change you won't get stuck with a machine you can't upgrade or get parts for.
One thing that gets glossed over is the control electronics and the quality of the power controller, interfaces and wiring. One vendor (already mentioned by Eric B) builds a controller that resembles an IED. Case is cut on plasma, bent up and wires are all wrapped and soldered in a giant tangled bundle. What you can't see CAN hurt you!
Nesting is over hyped. Most programs nest the drawing (DXF) and make the CAM process more involved. Some do a fair job but unless this is something you do on a daily basis the increased cost and manual cleanup aren't worth it. Most of the programs get you close but you still have to check them and make edits. Really good prograrms are really expensive.
Check SheetCAM for plasma and shape cutting.
www.sheetcam.com. It does not have auto nesting but does support part duplications, Arrays, and on-screen placement.
tomCAUDLE
www.CandCNC.com
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