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phill05
03-02-2014, 10:17 PM
Would it be possible to manually control the movement of a stepper motor with a simple forward / reverse trigger switch off a pistol drill and what else would be needed to set it up.

What I am thinking is the operator is manually moving a workhead left to right at the end of the run press a button or trigger switch to move the workhead down ie: put a cut on, move right to left all without taking his hands off the workhead, at the end of the job move to park area, press button / trigger switch up till it touches a limit switch and finish ready for loading next work piece.
If operator takes his hands off the workhead whilst moving the machine stops.

Phill

EddyCurrent
04-02-2014, 10:30 AM
Unless I misunderstand you, is this any use ?

CNC Wireless MPG MACH3 Remote Controller WHB04-L 40M w/ Electronic Handwheel l | eBay (http://www.ebay.co.uk/itm/CNC-Wireless-MPG-MACH3-Remote-Controller-WHB04-L-40M-w-Electronic-Handwheel-l-/300948825903?pt=UK_Sound_Vision_Other&hash=item4611f2a72f)

People use X Box controlers and all kinds of other things too.

phill05
04-02-2014, 11:33 AM
Hi Eddy
sorry no it's not what I was thinking,

think of a standalone stepper motor not connected to a computer all I want to do is make it turn ccw & cw with say a trigger switch from a hand drill or two buttons is it possible to do, and if so what else would I need to make it work.

Phill

routercnc
04-02-2014, 12:33 PM
If you really want to move the CNC machine independant of a PC then you can in theory connect a function generator to one of the step/pulse inputs to a BOB. It would move the motor at the speed set by the function generator. Select square wave, ~5v output, frequency set to give the required speed. For direction you need to supply 0v or 5v to the direction pin.

If you do this you probably need to isolate the PC parallel port temporarily to avoid putting 5v into an output.

I believe this is essentially what the MPG does but it goes through the software to retain position.

If you go direct you are bypassing Mach/Linux so I think it would completely loose position.

Perhaps a macro would be a better option assigned to a spare button on an MPG.

EddyCurrent
04-02-2014, 12:46 PM
If you search for, PIC chip, Arduino, Raspberry Pi, in the context of cnc controller you are sure to find what you need.

This might be one ?
http://www.mycncuk.com/forums/motor-drivers-controllers/6677-stepper-controller-manually-input-specific-degree.html

phill05
04-02-2014, 12:48 PM
Thanks Routercnc,
It's not what I am looking for, forget the machine, no cnc, no computer, loose stepper motor is sat on a bench is it possible to power it to turn CCW & CW with a trigger switch off a pistol drill or 2 buttons and what other components would I need to make it work.

Phill

Gary
04-02-2014, 01:04 PM
This can easily be done with the uim2430.
Search - Zapp Automation Ltd (http://www.zappautomation.co.uk/en/search?orderby=position&orderway=desc&search_query=uim243&submit_search=Search)

phill05
04-02-2014, 01:06 PM
I'll try to explain a little better, this is not a cnc machine, but it has an X axis left to right, the guy holds 2 handles 1 in each hand when he has moved to the right he has to manually move the head down IE: put on a cut but when he take 1 hand off the handle does not matter which handle the spindle stops rotating. the machine only rotates when the guy has both hands on.
What I want to do is put a stepper motor and control it with either a trigger switch or two buttons for the guy to power the head up & down without him taking either hand off the handles and the spindle keeps revolving.

Phill

phill05
04-02-2014, 01:10 PM
This can easily be done with the uim2430.
Search - Zapp Automation Ltd (http://www.zappautomation.co.uk/en/search?orderby=position&orderway=desc&search_query=uim243&submit_search=Search)

Gary your great this is what I am after away to place and order now.

many thanks

Phill

Jonathan
04-02-2014, 01:30 PM
It's a pretty trivial thing to program on to a PIC, or an Arduino if you're so inclined. That's unless you've never done any programming.

If you've not got a PIC programmer, or don't know someone who has, then using an arduino is probably the cheaper option. Something like this:
e.g.
Official Arduino UNO Rev3 R3 328 ATMEGA328P Board with Free USB Cable | eBay (http://www.ebay.co.uk/itm/Official-Arduino-UNO-Rev3-R3-328-ATMEGA328P-Board-with-Free-USB-Cable-/390566102831?pt=UK_Computing_Other_Computing_Netwo rking&hash=item5aef8dc72f)

Gary
04-02-2014, 01:47 PM
If you have just placed an order, I think you have ordered the wrong product. The uim24004 is a normal stepper driver. You need look at the uim243 range. These have the pulse generator built in.

irving2008
05-02-2014, 03:27 PM
Gary, does the uim243 have an inhibit/limit input? if not then wont do what OP needs as he wants a parking feature too.

I'd use an Arduino with a stepper driver shield, its quick, cheap and easily adaptable.

Phill05 - pm me if you want some help on this.

Gary
06-02-2014, 11:06 AM
Gary, does the uim243 have an inhibit/limit input? if not then wont do what OP needs as he wants a parking feature too.

I'd use an Arduino with a stepper driver shield, its quick, cheap and easily adaptable.

Phill05 - pm me if you want some help on this.

This UIM243 is a very simply and easy to use product.
It is a stepper driver that has a pulse generator built in and can either have an external 0-5V speed reference or use an inbuilt in pot for the speed.

It has an enable and run input.
you can use the run or the enable in conjunction with limits, but a park feature would need a bit more logic behind it.

Robin Hewitt
06-02-2014, 01:18 PM
You'd need four switches.

2 DPCO to control the current direction in 2 coils

2 SP to decide which coil(s) gets energised.

As soon as you add a stepper controller you need to debounce the switches.