Gate / Bridgeport Interract / Project

[Neale]

Bit radical, but....

Why not get a cheap MPG? Plugs straight into PC/Mach3, gives you ability to "wind" table, and you can set up buttons to do things like start/stop spindle while you are doing "manual" machining. My own (smaller) CNC mill has pop-out handles for manual operation but as soon as you disable servos you have lost DRO function, and you need to rehome before any CNC operations. I use the MPG a lot for manual positioning, even if I enter a line of gcode to do a controlled cut in place of twiddling the MPG knob at a steady speed. MPG can move table faster than I can wind the table handwheel as well!

[kingcreaky]

Bit radical, but....

Why not get a cheap MPG? Plugs straight into PC/Mach3, gives you ability to "wind" table, and you can set up buttons to do things like start/stop spindle while you are doing "manual" machining. My own (smaller) CNC mill has pop-out handles for manual operation but as soon as you disable servos you have lost DRO function, and you need to rehome before any CNC operations. I use the MPG a lot for manual positioning, even if I enter a line of gcode to do a controlled cut in place of twiddling the MPG knob at a steady speed. MPG can move table faster than I can wind the table handwheel as well!

Hi Neale, thanks for thre reply.
Sorry, i didnt say, The machine has a pendant with a jog wheel,

http://www.vistacnc.com/manual_downl..._P4-S_v4.0.pdf

and it IS useful, I take onboard the advantages you mention. they are the reason I bought it!. I find it too clumsy, maybe im using it wrong...
Lets say you have Carbide cutter in the collet, thats just cost you 70 notes, and your trying to manually set the home point by nudging the side of it up to a piece of steel plate, you have a rizzla in one hand your using as a feeler guage, and then trying to approach slowly enough with the pendant.. as you have no feedback in the jog wheel, lets just say ive had some accidents.
By emplying oldshool handles, its increased the functionality of the machine, even if its just for homing

[Muzzer]

Jog the tool to around 8mm from the work, then slowly jog it away until the shaft of a 10mm end mill will just slide between the tool and the work. Then you know you are at the 10mm position. This avoids chipping or breaking the tools and works for both mills and lathes.

But the correct way to look at this is that you need to buy an electronic probe, as it will transform your work accuracy. It's just the excuse you needed!

I never use the handles on my mills or lathe now. The MPGs give much more flexibility and control. I used to have handles on the Bridgeport and Bantam conversions, thinking it would be useful for manual operation but ended up removing them, as it improves the response of the servos.

[Neale]

I had a very quick flick through the manual and it seems to have similar controls to mine. I use a WHB04 (I think, from memory) which seems to be available from a whole bunch of different online sources. It works slightly differently depending on the system you use it with - I have used the same device with Mach3 (which I used with an Ethernet Smooth Stepper as well), UCCNC, and MyCNC. They all provide a continuous or step mode, though. In continuous, you select the axis and the speed range, and the axis moves while the wheel is turning. Good for rapid positioning. In step mode, you choose the step size and each click of the wheel moves that amount. Typically, I use 1mm steps for initial positioning, then 0.1 or 0.01 steps for fine adjustment. That works with the fag paper method pretty well! It has the advantage that because my machine has ballscrews and Hiwin rails anyway, the table moves very easily and there is very little feel on the handwheel. "one click at a time" is actually more precise once you are down to the 0.01mm setting. My MPG also has a couple of rotary switches for axis selection and step size selection so I can pretty much use it without looking at the panel while watching the work and tool. I'm surprised that you say that there is no feedback through the handwheel - I can be confident that an axis will move by a very precise amount for each click of the wheel.

But different people have different ways of working and all our machines are different. I just find it so much easier and just as accurate and sensitive to stay in the "software in control" mode but then, I had been using my home-built CNC router before this where I had absolutely no manual control of axis movement except via the keyboard or MPG, so I just had to get used to it.

I'm sure that this is the kind of thing that brings out strong feelings in people - be interested to hear other views. For me - big tick in the box for MPG!

[JAZZCNC]

Hey, look who's back, nice to see you here again Matt.

If you want to knock out the servos just fit a switch to the servo ON signal, but knowing you I bet you're not using it..

But that said I'm with the others and would use a Pendant, also the handles will affect servo tuning.