Gantry oxyfuel / plasma type machine from scratch

Ok, I got this searching the forums and internet. So would be needed to test it to see eventually how that latency would be affecting it. Another question is if there is an better suitable industrial PC to buy ?

I mean do you have any recommendations on what motherboard and chipset is preferable for use with LinuxCNC ? I understand that this would be any motherboard
that Debian or linux kernel supports, but is there a some preferred hardware list or suggestions for a good LinuxCNC industrial PC ?

tommylight wrote:

That would be redundant as LinuxCNC is the motion controller.
In short:
-buy a Mesa 7i96S and a THCAD

I was wondering if I should buy direclty the 7i95T as it has all needed i/o and encoder feedbacks for up to 6 axis.
What you suggest ?

I plan to set up a separate head in the future for plasma and who knows maybe even a spindle for drilling.

For such a large machine upgrading from the 7i96s would be a smart move as io is limited (but you can add extra boards). eg. Depending on your needs 7i76eu, 7i95t, 7i97t.

Note that if you do fall back to ethercat, with beckhoff, you just need to add an extra input or output module at any time as required at a cost of about $50 for another 8 ports.

Don't forget LinuxCNC can handle about 8 spindles so the drill could get a free ride on another Z axis stage if you are creative.

Does your table have downdraft zones?

rodw wrote:

For such a large machine upgrading from the 7i96s would be a smart move as io is limited (but you can add extra boards). eg. Depending on your needs 7i76eu, 7i95t, 7i97t.

Ok, I was just thinking that buying it once for the complete machine would be easier and more clean instead of adding the various boards per needs. Also because time sometimes makes obsolete something and its difficult to
find later.

rodw wrote:

Note that if you do fall back to ethercat, with beckhoff, you just need to add an extra input or output module at any time as required at a cost of about $50 for another 8 ports.

In fact the initial idea of going with EtherCAT was exactly to prevent not having the possibility to add later
some functionalities. To me seems that more and more industrial stuff is going EtherCAT direction.

rodw wrote:

Don't forget LinuxCNC can handle about 8 spindles so the drill could get a free ride on another Z axis stage if you are creative.

ok thanks for that info. I will have to struggle a lot with it, I know

rodw wrote:

Does your table have downdraft zones?

What you exactly mean by "downdraft zones" ? I have not yet build the table where the workpiece will sit on.
But the gantry is already existing and here are some pictures of when I received it. brastrak.com.br/files/cnc/

tommylight wrote:

saxa wrote:

I was wondering if I should buy direclty the 7i95T as it has all needed i/o and encoder feedbacks for up to 6 axis.
What you suggest ?


Yes, that would be better, but finding it sometimes not easy,
With Mesa, you can add inputs and outputs and PWM and encoder feedback as you see fit:
-more IO = 7i84 or 7i70 or 7i71 or 7i72
-more encoders = 7i85 or 7i85S (not the same, only half the same)
-more PWm for +-10V servos = 7i83

Many thanks, will take a closer look to those.

saxa wrote:

What you exactly mean by "downdraft zones" ? I have not yet build the table where the workpiece will sit on.
But the gantry is already existing and here are some pictures of when I received it.


 

Some large commercial tables have a central exhaust duct down the side or up the centre and as the torch passes into a zone, a gate opens and the others close (usually by pneumatics) so the draft is centralised in that particular cutting zone. It is possible to track the torch position and activate the relevant zone with LinuxCNC. The dust is usually filtered and the exchaust ducted outside of the building. I did write a component that did this for another user which triggered a bank of air solenoids.

rodw wrote:

Some large commercial tables have a central exhaust duct down the side or up the centre and as the torch passes into a zone, a gate opens and the others close (usually by pneumatics) so the draft is centralised in that particular cutting zone. It is possible to track the torch position and activate the relevant zone with LinuxCNC. The dust is usually filtered and the exchaust ducted outside of the building. I did write a component that did this for another user which triggered a bank of air solenoids.

Rod, you catched me, thanks for this heads up. I have not even thought about that problem of exhaust gases and
pollution stuff. I was thinking to make a water based table under the torch, but this solves just partly this
problem of gases. We have a luck of being in a country where its hot the whole year so everything is open and ventilated, but that does not mean I dont need it.