My turn for help with Pulse multiplier for test rig.

[EddyCurrent]

This does not directly answer Dean's request but . . .
If I was building cnc machines I would have as a minimum a box with a bob, power supply, 2 x stepper drivers, vfd, all wiring to a bank of terminals to allow easy connection of limits etc.
This would be connected to a PC with a parallel port running Mach3, there would be two sockets mounted on the outside of the box so that by using a flying lead, individual stepper motors could be connected or if the machine used two steppers on X this could also be accomodated.
This system would allow use of a remote pendant or you could use the Mach3 interface to directly enter G0 codes for moving the axes around, the bob would allow connection of limits and home switches for test purposes.

I believe this would cover all the requirements specified by Dean in the most productive and hassle free manner and from what I've read he probably has all the required parts already, unless of course he has some other, not yet revealed, idea for using the minimalistic approach.

[JAZZCNC]

I believe this would cover all the requirements specified by Dean in the most productive and hassle free manner and from what I've read he probably has all the required parts already, unless of course he has some other, not yet revealed, idea for using the minimalistic approach.

Yes I do this already eddy, I have a test rig setup with BOB, SS and 4 drives VFD etc so can test a machine is fully working while on the bench but some times I need to move an axis SINGLE axis away from the bench or before all wiring is done IE short stepper wires so I want simple portable unit to do this. Also some times I have more than one machine on the go and at differant stages of build so Don't want to have to lug PC and all the stuff to machine if it's not on the main bench.

[irving2008]

Hi Dean,

You wanted a learning experience so I deliberately left some info off the diagram. :)

These chips come in various package formats, the suffix identifies which so decide how you're going to build it and get the appropriate version. If you're breadboard it you need the PDIP package.

I don't foresee any major changes and these chips are only 30p or so so get them. Maybe even a couple of each just in case :)

I do need to consider Jonathan's valid suggestion re direction so there will be a v0.2 shortly.

[JAZZCNC]

Hi Dean,

You wanted a learning experience so I deliberately left some info off the diagram. :)

Good man I like a challenge. . Lol

These chips come in various package formats, the suffix identifies which so decide how you're going to build it and get the appropriate version. If you're breadboard it you need the PDIP package.

Yes BB at first then will probably make a better job with a board.

I don't foresee any major changes and these chips are only 30p or so so get them. Maybe even a couple of each just in case :)

I do need to consider Jonathan's valid suggestion re direction so there will be a v0.2 shortly.

Ok there's no rush so I'll wait until everything settles down then just buy a load of bits at same time and I'm sure there'll be plenty of Magic smoke in the air so I'll get spares. . Lol

Not being savy with these electronictrickery gismo's then it's probably technical chip stuff why it's a problem but Won't the drive take care of the Direction just with 5V on the Dir pin.?

[Jonathan]

Post #48-49: Looks like that was meant as a serious comment - sorry I didn't realise.

Not being savy with these electronictrickery gismo's then it's probably technical chip stuff why it's a problem but Won't the drive take care of the Direction just with 5V on the Dir pin.?

If you apply 5V across the DIR pins the motor will spin one way, apply 0V (or leave disconnected) and it will spin the other way. You could could do that simply with a switch if you're happy for the machine to go in the direction set by the switch, not follow the direction in which the MPG is spun.

[JAZZCNC]

If you apply 5V across the DIR pins the motor will spin one way, apply 0V (or leave disconnected) and it will spin the other way. You could could do that simply with a switch if you're happy for the machine to go in the direction set by the switch, not follow the direction in which the MPG is spun.

Obviously I know this and thats what I've been doing just with MPG. This is what I've been saying I just want it simple so flicking switch is fine and spinning mpg just for movement. Just I need faster than the single pulse the MPG spins at but still want the abilty to single step when needed.

555 + MPG would work and would probably be simplist but I don't mind playing and want to learn something in the process and so long as Irving or some other kind sole doesn't mind giving directions then I'll wait and see all the options.!

[EddyCurrent]

Here's another idea.
I used to work on plant where Selsyn Motors were used for synchronisation purposes and remote indication. It occurred to me that stepper motors were very similar so a quick search found this;
Fun with Stepper Motors - Synchronous Operation without Power - YouTube
No external electrical power required just a crank handle on a spare stepper motor.

[JAZZCNC]

Here's another idea.
I used to work on plant where Selsyn Motors were used for synchronisation purposes and remote indication. It occurred to me that stepper motors were very similar so a quick search found this;
Fun with Stepper Motors - Synchronous Operation without Power - YouTube
No external electrical power required just a crank handle on a spare stepper motor.

Ye played with this before and while it will turn another motor on the bench there's no torque obvioulsy due to low current/volts.

[irving2008]

if you're ok with a switch for Dir then there won't be a v2 at the mo.

Suggest, if not done already, you download & print off datasheets for chips and get a handle on what each does.

[JAZZCNC]

if you're ok with a switch for Dir then there won't be a v2 at the mo.

Suggest, if not done already, you download & print off datasheets for chips and get a handle on what each does.

Yes that's fine Irving and yes data sheets already downloaded but not looked at yet.