Giganto CNC printer documentation

So, here begins the journey of cleaning up the giganto CNC and breathing some new life into it. (Wiki is broke so this will be the makeshift info page)

General information

  • Signal voltages

  • Step + direction signals: These originate from the parallel port breakout board, and require level shifting to 24V (HTL) for the LUST motor drivers. (other option RS422, chose HTL due to simplicity)

  • Enable signal: Each of the motor drivers have an enable pin, 24V active high (internal power supply). These will be run to a 3 pole relay in the control cabinet, triggered by the parallel port board (enable signal enables all drives). Unless a 5V coil relay is found this will also require level shifting. VFD may or may not be connected here too. This may end up being permanently pulled high, as there is also a start input required (may be automatic, turns on the drives power stage) and an emergency stop input to engage the brakes/decelerate the motors.

  • VFD speed control will be a 0-10V signal from the parallel breakout board.

  • Mains voltages:

  • 240V: Due to the wiring available at our 3Ø outlets, there is currently no 240V available in the control cabinet (no neutral). To remedy this a 240V inlet socket will be installed, to separately power any 240V gear (computer, power supply etc). This is undesirable as if it’s unplugged when in use, bad things will happen. A contactor may be installed to ensure both supplies are present when in use.

  • Power supply

  • The original LAMBDA supply had some weird enable interface that was becoming a problem. Instead a Boneyard supply has been used, with 5, 12 and 24V rails. These have an unknown current limit however it should suffice.

  • This will power a majority of the control gear: parallel interface board, level shifter, control relays, motor brakes (through LUST drives)


  • Far too much. That is all.
  • Troubleshoot interface/settings of LUST drivers
  • Determine inputs for LUST drivers, enable, start and emergency stop? (see enable signal under general information)
  • Terminate the endstops to a terminal strip for further use.



  • X axis: Transtechnik SM 100-50-030-P0-45-R1-B1
  • Y axis: Transtechnik SM 100-40-050-P0-45-R1-B1
  • Z axis: Transtechnik SM 100-50-030-P0-45-R1-B1
  • Spindle: Perske VS 50.09-2


  • 2x LUST CDD.34.003.C2.0
  • 2x LUST CDD.34.005.C2.0 (1 spare)
  • Telemecanique Altivar 31 VFD (spindle control)

Power supply
- LAMBDA Vega 650

  • Unlabeled boneyard supply. 5, 12 and 24V out.

Proposed components


Wiring diagrams

  • Pinout/wiring for motor to driver. This isn’t an ideal setup, but it works so I’ll let the sleeping dog lie.

  • Potential mains wiring diagram. Relay to disconnect 3Ø supply if 240V supply is interrupted. This might be a bad idea, possibly better to tap into e-stop signal to LUST drives - active low, so run off 240V/24V PSU? Circuit breakers for VFD, LUST drives, 240V outlets, control gear (PSU) and welder/plasma cutter. If adding capacity for plasma cutter, 240V may have to come from a higher current 3Ø (16A) outlet, if a neutral is present at said outlet. Probably going to overload a typical mains outlet with it.

Build log & thoughts


Will attempt to drive the servocontrollers with some manner of external multivibrator. The operation manual mentions the time response of enable inputs which may have to be considered, however the start control isn’t being used implying that’s not very important. Also worth putting a LED on the reference reached output pin to see if it thinks it’s done. (4-36 application manual)


  • The level shifter was constructed and connected. However, due to the nature of this circuit a voltage divider is created with the 1/1.2K pullup resistor (turns out these get a bit warm, dropping 24V) and the 3K pulldown in the LUST drivers. At present I’m not sure if this is a problem, but the drives specify a control input voltage of <5V for low and >18V for high. The voltage divider created hits ~18V, however the drives to seem to recognise this when checking the input states of the pins.

  • The kiosk has been reformatted with Windows 7 and had Mach 3 installed. Currently this appears to be producing the output signals required, and the drives have responded to the direction signal (using step/direction), however the step signal was largely disregarded. At present I am under the impression this is just a setting that’s wrong in the drive. It is also possible the step pulse isn’t enough to get over the 18V threshold, however toggling the pins on the parallel port manually had the same lack of effect. Next step will probably be hooking the function generator back up to the driver to get a nice clean 24V squarewave for step input and fiddling around with the settings from there.

  • Lastly, the power supply was swapped to a boneyard find as the initial LAMBDA supply was giving @Hally and I some grief with finding the enable input. No specs/model on this new supply but it seems to do the job so far.

16/1/15 18:26

  • Hobbytronics design seems best. Will make our own version with 6 channels, along with two relay driver channels (enable and a spare).

14/1/15 19:20

  • Will use the parallel port driver thing. Gotta find something to do 5 to 24V level shifting. Might have to rig up some boards with MOSFETs and resistors and magic.

This will be edited to update content.


ooo documentation :heart_eyes:

Great work @Thermoelectric

Nice work. Looks great! Keep it up. +1

For those interested (and didn’t see last night), we got it to move along the bed. Hopefully once the shaft joining the two sides is completed it will magically become more rigid!


That shaft won’t take much to finish off now. It’ll be solid as in no time.

Glad to see someone taking over this and progressing nicely.

I can see why those motors were giving you grief, they’re wired very oddly.

So the level shifter and parallel port breakout board have been made/connected. So far the drives appear to see the step and direction coming in but are not paying much attention. More poking around is required.

did you leave the handbreak on?

enable/break commands?

Did you get the OS installed on the kiosk PC? If not, I’ll bring something in tomorrow night and do it. Any preference for flavour? XP/Win7?

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@sirhc I’m not sure what he likes. But make sure it’s 32 bit. 64 bit is a bit of a pain with serial ports.

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Linux would be preferable, for many obvious reasons.

What flavour of linux?

cookies and cream.

um, it honestly doesnt matter, I think most people like ubuntu? its @Thermoelectric’s call in the end though since he probably knows what his software reqs are.

I’m really not too fussed as to what goes on there. I installed Win 7 as Win XP is a little outdated, and Mach 3 probably doesn’t run on linux (Sven?).

As for the issue I’m having, it seems to be downline of the computer. The drivers seem to pick up the signals being there (when manually setting the parallel port pins high/low) however don’t seem to step with it. They were responding to direction at one stage however.

@Hally, nothing that easy unfortunately. Brakes were off and drives were enabled.


@Thermoelectric @devians

As much as I love my Linux, Mach 3 just doesn’t run on it.

The motor wiring doesn’t seem at all right compared to the documentation - the motors have resolvers (not encoders) that need to be connected to X6 on the drivers, and the holding brake needs to go to pins 18-20 on X2. That’ll probably cause a bunch of issues getting the motors to run.

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Apparently I didn’t update this much. Encoders vs resolvers - I wasn’t really sure what the difference was so I was using these terms interchangeably. As for the connection, I remember they went to the front of the drive and they were wired hella weird but the drives would run the motors fine, so whatever the wiring was on them it seemed to work.

Holding brake wise, I think I didn’t bother running these through the drives at the point I was at, as it was just one extra thing to mske my life hard. Powered them directly from the PSU and all was good.

The problems I was running into near the end was just getting the resolution out of the motors/figuring out the best way to control them. I was treating them as stepper motors so they weren’t performing as I was expecting. Probably just needs some better control method in there, just didn’t get that far.

One major hurdle that is still requiring attention is driver to controller interfacing. I tried HTL signalling and it was insanely noisy once the drive power stage came on. Could have been a number of things but shielded rs422 is looking like a better option. How we’ll get this out of a Smoothie or gecko board is still being thought out. Probably some ttl->485 modules from eBay. (Note: the expensive ones. I’m willing to bet the $1 modules will have a reliability similar to that of the cheap rs232->ttl converters used with the netrols, being horrendous.)

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I’m about to do a mass ordering of boards and electronic bits.
If you think it would be easier with a custom board, more than willing to help out and add it to the order.

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That’d probably be very handy. I’ll have to have a proper look later but we’ll need 2 RS
422 channels per drive so… 6 all up? A couple of transistors for driving relays would also be super handy if that could go on the same board.