I've got a taig. I don't think .0005 is quite accurate. Mine works well to about .001. Twice as much. I could tighten the nut down more, but you get to the point where the included steppers either can't run the machine or you tear things up because the motors are working harder. Because all of the Taig's adjustments increase friction of sorts (the ways have a tapered piece that tightens or loosens and the leadscrew nut has a brass screw that opens and closes) you run into issues as you try to go faster and with higher accuracy. I find that I can get 15 IPM on all axis with repeatability of about .001. If you were to go with a ballscrew you could be significantly faster with the right motor.
I would buy Taig's CNC ready machine and add your own motors and drivers. You will be ahead in the long run. Taig's motors are unipolar, and the included drivers are phase drive, not step/direction, which limits your driver software options.
I would buy Geckodrives and bigger unipolar steppers.
The only other beef with the Taig is proprietary collets. They limit you to a 5/16 tool diameter, which means you can't use 3/8 tooling which is VERY standard. You can work around this, but you need a lathe. Buy a bunch of taig's spindle blanks and you can bore tool holders to whatever size you want. I have a fly cutter with a 1/2" shaft in one and it works great.
The spindle motor as supplied is on the weak side. (1/10 HP) The speed drive is adjustable by pulleys and my motor won't start the spindle every time at the fastest setting. Once it is moving it isn't a problem. For the slow spindle speed you would want it isn't a problem.
The taig will cut steel without any problems. Just go slow. You will probably also need a reflow coolant system to do that.
I wouldn't hesitate to buy another one if I had a need. It is a sturdy machine, and I haven't had any problems with the actual operation. I would build my own control system around their CNC ready mill if I could do it again.  |