Help with Z axis and THC upgrade

[finyuk2005]

Hi there
Im in need of some help! i think i have done too much reading and am now going round in circles trying to work out what direction to take!
I have been retrofitting an old plasma table with a new csmio ip/a motion controller, X and Y axis are both working great now, but the Y axis was controlled by a separate standalone unit, called an Innerlogic rsvp 401hd, it was Y axis hight, auto voltage control and servo driver all in one box,
I cant get the voltage control to work at all, and am struggling to get everything to be timed correctly with mach 3, I would also like to have control of the Z axis with mach 3, and plan to do a rotary axis at some point so Z axis control would be handy!

As far as i can figure out so far, i could either; use something like a gecko G320 driver to power the original dc servo motor, but i would need to change the encoder as currently it is a 24v one, and the gecko needs a 5v encoder, and also i am not 100% sure the csmio IP/A controller can give step/dir signals as it is a -10v/+10v controller.

So it might be easier to just buy a new stepper motor and driver, something like this,
https://www.cnc4you.co.uk/Stepper-Motor ... o_Kit_4NmB

Or i have even seen whole new Z axis kits for not that much money, would be a shame not to use the perfectly good original one though, it already has limit switches etc installed

Initial torch hight was done with Ohmic sensing and i think by monitoring the current from the servo motor, would something similar be possible? i have seen you can get modules to do the ohmic sensing, not sure about the motor current thing though.

As for torch hight controller, i think i have decided on the proma thc150, seems like it would do the job and be reliable, any others to consider?

sorry for the billion boring questions, but any input is gratefully received!!
cheers

[robertspark]

https://www.westermans.com/downloads/in ... ev%202.pdf

You can probably more than likley reuse the z axis.

If it were me I would try to work out the bolt spacings and the shaft size to see if I could find a nema17,23,24,34 to fit in the gap.

photos would be helpful showing the wiring arrangements to try to help.

I would not recommend a proma 150.... but each to their own (been there done that!)

the cismo is a nice drive, I did consider it many years ago.... but it was rather expensive and did not offer anything over anything else. It does have a plasma cutter THC option within it if you can get an analog voltage signal into it.

https://en.cs-lab.eu/product/6-axis-cnc ... -software/

CS-labs also do their own cnc software now (was not an option when I was shopping for a Mach3 replacement).

https://en.cs-lab.eu/product/presale-si ... re-cs-lab/

https://en.cs-lab.eu/connection-of-thc- ... c-digital/

[robertspark]

.. i am not 100% sure the csmio IP/A controller can give step/dir signals as it is a -10v/+10v controller...

The CSMIO IP/A is for ANALOG drives not for step & direction stepper motors . (as you've identified it outputs -10V / +10V)

Sorry never used an analog drive so cannot advise on that one.

[robertspark]

you may be able to remove the motor and use an adapter plate to change it to another more conventional drive like a nema 23 say

if you use something like a 2mm thick adapter plate with studs welded on both sides, if you can get nuts in position.... or something like a 4mm plate using countersunk screws and studs for the replacement stepper motor...

photos?

2022-05-30 15_07_32-innerlogicrsvp-401 hd 115v system manual-rev 2.pdf.png

[finyuk2005]

Thanks for the replies!
Yeah doing more reading it does seem I am limited to drives that would accept the +-10v analog inputs which makes things a bit harder, bound to be some drives out! been reading up on AC servo motors, a slightly more modern equivalent of my dc servos i think.

Any reason you didnt get on well with the proma THC? and what did you end up using instead?
http://www.razordance.co.uk/THC.htm
I did see someone recommend this one, which would be handy for me being in the UK

cheers

[finyuk2005]

Is the robot3t THC3T-02 any good do you know? as i was looking at their ohmic sensor box anyway

[robertspark]

i am in the uk too nr liverpool.
ill respond later regarding options as you have a few

[finyuk2005]

That would be amazing thanks!

I have been trying to look for servo drives that accept +-10v, seems it would be worthwhile to go for AC servos, see if i can find a kit mayby.

cheers!

[finyuk2005]

Took a few pictures of the Z axis, had a look under her skirt
Quite interesting to see the three magnetic (i think) limit switches, and also what im fairly sure is a wee magnetic brake on the bottom of the screw,
will try and upload some pictures

[finyuk2005]

a few more

[robertspark]

Options for THC are:
http://www.razordance.co.uk/THC.htm
This is a bit of an intelegent THC in that you can pass it the setpoint and it will track that setpoint. It is MAch3 compatible but I don't think it is Mach4, or anything else directly compatible.
It was designed and is sold but a guy that used to frequent the Mach Forum (went by the handle stirling)

There is a note on the website:
These days, any decent external controller should fully support THC. Examples, reported by users include the ESS (Ethernet SmoothStepper), The UC100 and UC300ETH range and CSMIO. However note that user supplied 24V to 5V level shifting is required to interface the CSMIO.

MiniTHC
https://minithc.com/
This one is going to be a difficult one.... given it's made in Russia.... and will no doubt be in short supply or on the slow boat from wherever to get around restrictions. I have one (they work well). But I'm not using it at present.
It just provides simple up and down control but it is possible to pass a value across to it as a setpoint


Price AHVC
https://xtremeplasma.ecwid.com/Pricecnc ... p236772120
Seem to be in short supply at present.
It just provides simple up and down control.
Lots of guys used to like these, they were sold {as a business} to xtremeplasma a while ago but have been on and off on supply I think since then.

You are really in a difficult position having gone down the CSMIO route..... I understand why as I expect that your servos are looking for analog input control..... problem is there are not many controllers about that can do that.

As far as I am aware the only others that can do that are:
LinuxCNC......
And I don't want to give you the hard sell.... but that has integrated THC.

But you have a sunk cost and I'm not sure if you want to consider another route.

[finyuk2005]

I had been leaning towards the razordance as an alternative to the proma, the price AHVC does look quite good, but as you say, out of stock like a lot of things on the xtremeplasma page.

I going to have to email a few websites possibly to make sure i get something thats going to work with the analog csmio IP/A
I does seem to limit me quite a bit, but the servo motors on the X and Y are proper old school quality beasts are working great with the IP/A so far, so i still think it was worth going that route... i think! ha ha!

Thanks for the help with THC's, there are so many out there its hard to decide!

[finyuk2005]

I have been looking at this driver;
http://www.adtechcnc.co.uk/qs7aa020m-servo-driver/
looks like it should work, just need to find the correct motor now
my hied is scrambled with all the different types of motors and drivers ha ha!

[finyuk2005]

Still trying to get my head round what motor to buy for the z axis, how do i equate the old dc servo at 48v and max 3.1amps to an AC servo?
Been reading lots of threads that talk about steppers of 270oz/in for z axis, but again, not sure how that equates to servos?
What kinda wattage should i be looking at for a z axis?

Decided on the razordance thc now at least!

cheers

[finyuk2005]

Bit of an update,
went with a dyn4 ac servo drive and motor setup for the Z axis, and a razordance THC,

I am getting really close now, but am struggling with P.I.D tuning, auto tune just doesn't seem to work, and often manages to blast past the limit switches which is annoying, will have a go at manual tuning after my dinner!
The dyn software setup tuned the drive perfectly and it hold position perfectly, so i think it is just in the csmio pluggin for mach 3 that i need to get tuned correctly

[weldguy]

Man that's a tough one, wish I could help. Sounds like your well on your way. Best of luck.