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createspacelondon
18-12-2014, 05:26 PM
Over here at Create Space in Wembley we have acquired a lovely 90's CNC mill, manufactured by a now insolvent company called Cybernetic Applications.

Have a look, it really is lovely craftsmen ship.

http://www.mycncuk.com/attachment.php?attachmentid=14119&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14120&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14121&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14122&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14123&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14124&stc=1

We are mainly wondering if any one on the forums recognises the stepper motors and can advise us on the variables for use with mac3?

JohnHaine
18-12-2014, 09:59 PM
They look like rather generic type 23 steppers. Almost certainly 200 steps per rev. How many wires do they have? I have a Denford Novamill of about the same vintage with the original motors and they work just fine with modern bipolar drivers and Mach 3. More important will be whether the drivers and any breakout board are compatible with Mach and a parallel port.

createspacelondon
20-12-2014, 06:02 AM
They look like rather generic type 23 steppers. Almost certainly 200 steps per rev. How many wires do they have? I have a Denford Novamill of about the same vintage with the original motors and they work just fine with modern bipolar drivers and Mach 3. More important will be whether the drivers and any breakout board are compatible with Mach and a parallel port.


thanks for getting back to us. there are 4 wires to each motor. We have gone for these drivers and bresak out board:

http://www.ebay.co.uk/itm/251665586352?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

We think they should work mach3. 200 steps is a good start tho, thanks.

JAZZCNC
20-12-2014, 01:16 PM
Can I just ask why your changing the drivers.?

Those drives you have already are probably better drives than those your buying.! The cheap ebay TB based drives are rubbish and blow up for fun.

Personally if the drives worked then I'd have just used them and connected to breakout board if it used a proprietry board which is often the case.

Regards Mach3 and setting up then you need to know a few details like screw pitch and the amount of micro stepping set on the drives.?

While John mentioned 200 steps think he was mostly meaning the Motors are standard 1.8deg motors which give 200steps per revolution.
In use you rarely run them at 200 micro steps as the motors run quite rough at this setting. Often micro stepping is applied in the region of 400-800 or for smoother running 800-2000. This is a setting on the drives.

Now the down side to higher micro stepping is that it requires more pulses from the parallel port to move the same distance or speed. So going to high isn't recommend with standard parallel port otherwise you risk potential for missed steps. Also on less important scale the max rapid speed you'll achive will be lower.
800Ms is a good balance of smoothness and speed for standard 25Khz parallel port setting.

So to set mach3 up for correct travel distance you need to know one main thing the "steps per unit" for each axis. This could be inch or MM.
You work this out by taking the Micro stepping amount and divide by the screw pitch or how far each axis moves for 1 revolution of the screw. IE: for metric units 800Ms / 5mm pitch = 160 steps perMM

Then it's just case of tuning the motors regards velocity and acceleration. How high or fast you can tune the motors depends on several variables, like Voltage used, Screw pitch, MS amount vs parallel port Frequency etc.
It will be trial and error mostly but the GOLDEN rule is you can't have both high velocity and high acceleration. It's one or the other or a balance of both works best.
If you go to high on either you'll cause the motors to stall. Esp the acceleration so start low and work each one up separately never change at same time. Start at say 1000 on velocity and 300 Accel and take from there.

Other things in Mach3 you'll need to set to get motors working are the ports n pins configuration, IE tell mach which wires to use to speak to which drive or switch etc.! The BOB will have pin numbers for motor outputs and any inputs, ie E-stop,limit swithces etc which you need to enter into machs related ports n pins settings.
Setting these wrong is a common cause for motors not responding or switches not working.

Good luck just ask if you struggle.