Lets address one at a time.
Noisy steppers: What are you using to get signals from the computer to the controller?
Bare-bones WinXP built-in PC that came with the mill. There's a proprietary BOB & manual controller board that hands off control to the PC/Mach3 when you put it in CNC mode. Manual mode permits spindle operation and MPG operation, but no native Gcode input. Connected via parallel port, no hardware motion controller (ESS or USBSS)
I'm guessing that you are running a metal working mill. Correct me if I am wrong.
Correct. 9x16 ish travels, linear rails, 5k RPM BLDC spindle. Pretty rigid frame for this size. R8 collet, using Royal QC system that came with it. No ATC. 4th axis is a stepper 90:1 rotary table, 10RPM max. This is the now-defunct predecessor to the biggest SkyFire mill.
You need a feeds and speeds calculator. There is subscription software available called GWizard Calculator. I use it regularly to avoid rubbing and maximize my cutting speeds.
Agree. Trialed GW and am trialing FSW. One or the other will get some money from me shortly. CNCCookbook is a daily stopping point for me. I should give him some money just for squatting on his site so frequently
Accuracy: This depends on mechanical backlash mostly. As long as steppers are not overloaded they will not skip steps. My overloads are almost always operator error. Trying to plow through 3/4 plywood full depth at 650ipm will definitely overload the steppers but the racket will give the operator a clue. Hybrid steppers will stop when they skip. Servos will try to keep up but cost is more. Your choice. My system is straight stepper but I built a homebrew with hybrids. My feeling was that I wasted money on the hybrids once I sized my steppers properly. Note that a lot of microstepping will rob lots of power. If you can tune the mechanicals for zero microstepping you will have a stronger system. Actually servo feedback goes to the servo driver in most cases. The Hind controller does have a provision for reading feedback from your spindle drive.
All commercial metal mills/lathes I've come across use servos, and I do intend to machine tough, expensive materials. If I do upgrade the axis motors and/or drives, I'll likely get some Nema34 750w DMM servos - bolt-on X/Y with a coupling change and some surgery on the Z-axis
Servos vs Steppers. Servos work a bit differently. The controller tells it where to go and the motor/driver moves until the feedback tells it that it has arrived. They hunt a little. Steppers are positive motion. When you tell them to move 1400 steps they move exactly 1400 steps (unless you overload them). For precision I would recommend steppers. Hybrids if you are running expensive materials and want to stop the machine on overload.
Again, any axis upgrade or replacement due to dead components will include feedback/encoders. I don't see the point of saving a hundred or two per axis when closed-loop is not extraordinarily expensive these days. The question in my mind is whether it's worth the headache and/or cost to select a controller that uses the axis feedback for motion control adjustment. I suspect not.
Hind is working hard to get full features available. They just added a biggie for me - probing. As yet they do not have the macro screen running so I will write a g-code routine to probe for z-zero and keep it on my stick.
4th and 5th axis as well as axis slaving I am told is coming very soon.
The Hind manual has a wiring diagram for MPG. You may be able to use your current one. I use a wireless keyboard and the JOG function. Check the online manual. Arturo has a link on his product page.
Keep in mind that the Hind Gen-II has only been available in the USA for a couple of weeks. The concept is better than anything I have seen and I am sure that they will be fully functional very shortly.
If you want touch screen it may work. They have tried it at Hind. As long as there is a USB interface. I'm kind of old school. I prefer a keyboard and plain screen. I can't see $400 for a touch screen and putting it out in my shop.
Already have a USB touchscreen, so no extra cost there. Good to know about the other features, and of course Hind & CNC4PC have been pretty informative with my various inquiries. It looks like a killer setup.
Bob