My PlasmaC Journey

[raumindustries]

I think Rod's table and his help have been limitless sources of info for myself and others here on the forum. I can't quite possibly understand why it's a bad thing to have a product take years to develop. We are all busy, no one is doing this for pay, and the collective hive mind is a very powerful tool.

Hey, "thefabricator", I'm glad you got your stuff working using Plasmac. This is a testament to how this project was intended to work - a product that works so well it can be used day in and day out by a commercial shop.

[Rodw]

Hi Rod,
I found nobody selling ohmic sensor for linux cnc ? If available on mesa, then will be easy. Everything from 1 source who know well about this linux. THCAD is out of stock, it looks like everybody move to linuxcnc plasma.

I hope thefabricator does not mind a small hijack.
For ohmic sensing, most people now seem to be using a circuit I developed in conjunction with Mesa which uses a THCAD-5, a $20 Meanwell HDR-15-24 isolated power supply, a couple of resistors and a software component I wrote which is found on the Linuxcnc forum (ohmic3.comp). I need to get that incorporated into Linuxcnc master branch! There is an earlier component of mine (ohmic.comp) as part of the Linuxcnc distribution but ohmic3.comp has some enhancements to better cope with water tables and water shorts inside the torch tip.

To use this, revised firmware is required from Mesa (available on the product pages at Mesa). This cleverly maps two extra Encoder A inputs on other encoder inputs on a mesa 7i76e or 7i96 so up to 3 THCADs can be used.

Mesa appears to have stock of the THCAD cards..... If in Europe, I would contact eusurplus to see what they have.

[Rodw]

I think Rod's table and his help have been limitless sources of info for myself and others here on the forum. I can't quite possibly understand why it's a bad thing to have a product take years to develop. We are all busy, no one is doing this for pay, and the collective hive mind is a very powerful tool.

Raumindustries, thanks for your support. I'm not sure if you know but the spaceship now runs stepper motors chosen from an amazing proprietary engineering model I was given access to. The motors are driven by Italian made stepper drivers suggested by Tommy in Kosovo. He's really the McGyver of plasma cutting building commercial machines from what was available in a war torn country. These drivers feed the motors 90 volts and with another linuxcnc component I wrote, run at 50% current while at rest or at constant velocity. This allows the spaceship to smash out 0.5G acceleration without motors overheating. (after I backed off the X axis from a neck snapping 0.8G). The model says I can reduce the current a lot further so I've been meaning to try reducing it to 30%. Unfortunately, the gantry ends were never designed for these sort of forces but eventually I will implement an improved design. But for now they serve their purpose. That was really my laser cutter's fault back when I built it as he could not bend 10mm aluminium without it cracking so I went with 6mm knowing I might run into troubles... My torture nest (Or is that test?) has pushed everything to the limits during my testing and I have overheated the plasma cutter, the motors and also the stepper drives themselves. Now they let Linuxcnc know before they miss steps so things stop more gracefully. I think I've solved all of those issues now after a lot of steel went into the skip!

Hey, "thefabricator", I'm glad you got your stuff working using Plasmac. This is a testament to how this project was intended to work - a product that works so well it can be used day in and day out by a commercial shop.

Yes I agree, there are commercial shops all around the world using Spaceship inspired Linuxcnc technology but few smash out so many heavy parts all day every day as thefabricator does. To his credit, he was the testbed for RS485 control using Linuxcnc. The original code was contributed by a Linuxcnc user in Mexico who does commercial retrofits and now with thefabricator's support, its embedded into Plasmac and included in the Linuxcnc distribution for everybody to use for free!

I've thought about keeping some of the IP I have developed to myself but I just can't bring myself to do it. As you say the collective mind of the open source movement is very powerful and to do so would betray those contributiors who have been part of the journey and stunt further development.

[thefabricator]

Hey, "thefabricator", I'm glad you got your stuff working using Plasmac. This is a testament to how this project was intended to work - a product that works so well it can be used day in and day out by a commercial shop.

Yeah that is my whole point of this thread, to show that a DIY built machine can be capable of running all day everyday and cut large amounts of parts.

The other thing is the reliability of the software. When your cutting a 3000x1500x25mm sheet of plate, the material cost is very expensive. If the software crashes while your in the middle of cutting and you screw up the sheet your out of pocket substantially. I cut 25mm plate every week with no issues. Words cannot express how happy I am with my machine!

[TJS]

That video is restricted. It won't play.

[thefabricator]

That video is restricted. It won't play.

This one?

[TJS]

That video is restricted. It won't play.

This one?

I got it to work. Seen it before. Thanks.

[raumindustries]

Raumindustries, thanks for your support. I'm not sure if you know but the spaceship now runs stepper motors chosen from an amazing proprietary engineering model I was given access to. The motors are driven by Italian made stepper drivers suggested by Tommy in Kosovo. He's really the McGyver of plasma cutting building commercial machines from what was available in a war torn country. These drivers feed the motors 90 volts and with another linuxcnc component I wrote, run at 50% current while at rest or at constant velocity. This allows the spaceship to smash out 0.5G acceleration without motors overheating. (after I backed off the X axis from a neck snapping 0.8G). The model says I can reduce the current a lot further so I've been meaning to try reducing it to 30%. Unfortunately, the gantry ends were never designed for these sort of forces but eventually I will implement an improved design. But for now they serve their purpose. That was really my laser cutter's fault back when I built it as he could not bend 10mm aluminium without it cracking so I went with 6mm knowing I might run into troubles... My torture nest (Or is that test?) has pushed everything to the limits during my testing and I have overheated the plasma cutter, the motors and also the stepper drives themselves. Now they let Linuxcnc know before they miss steps so things stop more gracefully. I think I've solved all of those issues now after a lot of steel went into the skip!


I've thought about keeping some of the IP I have developed to myself but I just can't bring myself to do it. As you say the collective mind of the open source movement is very powerful and to do so would betray those contributiors who have been part of the journey and stunt further development.

0.8G is pretty good! I'd love to get my hands on that motor sizing model!!!

What's very interesting is the lack of innovation I've seen in the commercial plasma market surrounding everything that's not "high def". This really means hobby and light commercial machines, usually up to 120 amps. If I correctly understand the technology, other than advanced plasma creation and attenuation, most of the upgrades are software related. I think the largest leap has come with cheap and efficient nesting softwares - now available built in with Fusion360 - although still a bit clunky there.

By my estimation plasma needs a few things to be competitive with Chinese import fiber lasers:

1) Cost effective - got to be able to get a machine installed for around half the price of comparable laser;
2) Small diameter:plate thickness holes must come out well - important for drawings that spec "no flame cut holes" as shops like "thefabricator" cant be using mag drills for all those knife plates;
3) the ability to add rotary (with or without bar feed) for tube processing;
4) speed - the table has to be fast to really keep the inherit weaknesses of plasma at bay;
5)perfect THC - seems this has been resolved;
6) reliable - these machines really should use off-the-shelf components that the average fabricator can repair on their own. I struggle to see why a guy in Australia must send a box back to the US to get fixed. Sure, things are proprietary here and there but I think there's a better way and to have more pieces be open-source. The open-source model can work well especially if driven by a few guys using it in a commercial application. Say a Z axis kit, or a sensor kit, or even a complete motion control kit up to a full table build. If a group is making money, then it's easier to provide support.

Rod, we thank you for your legwork flying solo all those years developing this stuff. We stand on the shoulders of giants now.

[cutnweld]

To The Fabricator,Is this something that the average mechanic could put together? I have a table and am very interested in doing what you did for various reasons. Like if I was to purchase control hardware would there be a lot of code needing to be written or is it available somewhere? Sorry if I'm not making sense but Im not up to speed on all electronics. Like I'm wondering if it is really as simple as you make it sound

[thefabricator]

To The Fabricator,Is this something that the average mechanic could put together? I have a table and am very interested in doing what you did for various reasons. Like if I was to purchase control hardware would there be a lot of code needing to be written or is it available somewhere? Sorry if I'm not making sense but Im not up to speed on all electronics. Like I'm wondering if it is really as simple as you make it sound

Hi cutnweld. I would say it is do able for the average guy to set up his machine with PlasmaC. I would recommend the Mesa hardware as it is very easy to setup, well I found it easy.

Have a read through some of these links on this thread, https://forum.linuxcnc.org/plasma-laser ... -one-place also the PlasmaC user guide, http://linuxcnc.org/docs/devel/html/pla ... guide.html

The user guide will instruct you on how to install LinuxCNC ISO with PlasmaC and how to set it up. With the Mesa hardware, I would recommend the Ethernet based cards as the step generation is done within the card and does not rely much on the latency of the PC. You will need a PC with OK latency but most old computers are capable of running the software.

Any questions reach out on the PlasmaC forum, https://forum.linuxcnc.org/plasmac

[manac]

I’m working on a cnc sharpie marker machine. (Will switch over to my 45xp when up and running)

I need 5 skill sets:
Learn/Design it all up. (In process)
Setup a Linux computer and install/configure Linuxcnc. (H2+ up and running Linuxcnc, no configuration yet)
Build table and axis. (Table built, 130 tapped holes for linear rails and racks)
Wire it all up. (Not Started)
Get it working.

It’s all out there, this forum and Linuxcnc are a great resource.

Having fun!

[thefabricator]

Setup a Linux computer and install/configure Linuxcnc. (H2+ up and running Linuxcnc, no configuration yet)

Once you get over the learning curve of setting up Linux and LinuxCNC, the Hal and INI files, the possibilities of what you can do with it are vast. It really is a great platform for CNC machines.

[cutnweld]

Hey thanks for your info and time, I think it is incredible how much power is out there to make and improve when all chip in. Would I be able to retain my original servos from Cand or would I need to start right from scratch again?

[Rodw]

Would I be able to retain my original servos from Cand or would I need to start right from scratch again?

Yes, there should be a solution to use your servos and servo drives with Linuxcnc. You would need to provide details of the servo drives used currently. It would be best to ask on the Linuxcnc Forum to gain a better audience once you have that info.

If you were using something like a Gecko G320X drive, the encoder input is connected to the drive, so you just need a step and direction board. If you are using a Gecko G251X or similar that would imply the encoders are terminated elsewhere so you'd probably need to add a Mesa 7i85 daughter card to close the encoder feedback loop.

[cutnweld]

Christmas! I ordered 3 clearpath CPM-SDSK-3421S-RLN 1094 oz in and 1 CPM-SDSK-2310S-RQN for the Z. Servo Power supply and Onlogic Ryzen industrial fanless PC, and Mesa 7I76E and THCAD-10. Now to see if we can get it to turn I know I will be told there's cheaper servo options but I've heard a lot of good about these and want to give them a try. My goal is 1000 ipm with at least .001 resolution, and I cant wait to benefit from the quick linux touchoff. Mach is pretty slow at that. Many thanks to the fabricator for stepping out with a commercial build, and to Rod for all the time and effort in linux programming. Sorry if I'm straying this post to many miles off track. Happy new year to all

[thefabricator]

Christmas! I ordered 3 clearpath CPM-SDSK-3421S-RLN 1094 oz in and 1 CPM-SDSK-2310S-RQN for the Z. Servo Power supply and Onlogic Ryzen industrial fanless PC, and Mesa 7I76E and THCAD-10. Now to see if we can get it to turn I know I will be told there's cheaper servo options but I've heard a lot of good about these and want to give them a try. My goal is 1000 ipm with at least .001 resolution, and I cant wait to benefit from the quick linux touchoff. Mach is pretty slow at that. Many thanks to the fabricator for stepping out with a commercial build, and to Rod for all the time and effort in linux programming. Sorry if I'm straying this post to many miles off track. Happy new year to all

Thats great to hear, I cant wait to see it cutting parts!

[asuratman]

and Mesa 7I76E and THCAD-10.

It is better to use THCAD-10 or THCAD-5 ? Since we can adjust from software/firmware ...

[Rodw]

If you can set the divider to 20:1 which most hypertherms allow, the THCAD-10 is a perfect choice. That gives a 200v full scale which is all we care about and you have good resolution. If you can only do 50:1, the THCAD-5 is best.

Some of us are using a second THCAD-5 for ohmic sensing with a Meanwell HDR-15-24 isolated power supply.

[asuratman]

I have downloaded linuxcnc-2.7.14-wheezy by both normal and zsync, but I got both in .rar. When I extracted file, I did not find linuxcnc-2.7.14-wheezy.iso file. So that I could not make bootable usb. What should I do ?

[asuratman]

I ran UUI and I found that rar is iso file ... txs

[robertspark]

all Isos here....

http://linuxcnc.org/downloads/

why 2.7

[asuratman]

I will upgrade to 2.9 afterward, that is only way I know ... I just follow utube ...

[Rodw]

I will upgrade to 2.9 afterward, that is only way I know ... I just follow utube ...

Please start with 2.8 the release version. 2.7 is too far out of date and does not support all the new features plasmac requires...

[asuratman]

Hi Rodw,
Is there any different if upgrading from 2.7 to 2.9 and 2.8 to 2.9. They are all become 2.9., its all the same ?

[Rodw]

Its a bit like installing Windows XP. Very old, The Linux OS version is past end of life, lack of hardware support for a lot of stuff and may not run the latest Linuxcnc software. I have never used it and started with 2.8 when it was the development version