# Mach3 Help-loading gcode wrong (picture doesnt match drawing)



## jimmyferg (Apr 10, 2020)

I am currently building a plasma table and I can run the pre-loaded .tap files and they look correct. If I draw one and run it through lazycam to convert, and I load it on mach3, it is just a bunch of squiggly lines. I am sure I am  missing a step, but i cant figure it out.

Thanks.


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## macardoso (Apr 10, 2020)

I've had an issue where my CAM program uses absolute ARC commands and Mach 3 was set to incremental (this is standard). I think that setting is under the general settings. Try it


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## jimmyferg (Apr 10, 2020)

macardoso--that was it thanks a lot. I may pick your brain on some other mach3 if possible.

Thanks again


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## macardoso (Apr 10, 2020)

Yup! I'm a long time Mach 3/4 user. Done a lot of Brains/VBA/LUA custom coding too. More than happy to answer any questions you might have.

If you needed to switch it over to "Absolute" to get it to work, you might want to check your CAM settings. The gold standard for G-Code interpretation is FANUC and their standard is "Incremental". That's why Mach 3 defaults to it. This may be an option to change in your CAM or post processor.


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## jimmyferg (Apr 10, 2020)

Thanks for the info. What is the best way to set up the motors? I have some "chatter" when they are running.


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## macardoso (Apr 10, 2020)

Very open ended question. Let’s start with your system.

What is the machine? Size and Weight? What motion controller are you using? How about what motor and drive?


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## jimmyferg (Apr 10, 2020)

The machine is of my design. cutting plane would be 5' x 10'. Weight, no clue what is the weight of which part you need? see attached page from where I ordered the kit. I didn't use the pulleys, I went direct drive. Let me know what else you may need, and thanks again.

Be safe out there.


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## jimmyferg (Apr 13, 2020)

Ive got the motors running pretty good. I actually dry ran a program today. What kind of relay do I need to have the computer control to turn on the plasma machine to cut?


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## macardoso (Apr 14, 2020)

Sorry I didn't get back to you. Totally missed the notification from your first reply.

Was trying to understand if you were building a 5 ton monster or a table top sized machine. Changes my advice

Looks like a solid design with Nema 23 425oz-in stepper motors and single axis microstepping drives. These shouldn't really chatter other than the hum of the drive's voltage chopping at the motor. If you hear chatter, groaning, or anything like that when it is stopped, then I'd be concerned you have noise problems.

Design for noise immunity is super important on a plasma CNC or the EMI emitted by the arc can cause real problems with your controls. You should definitely be using shielded cabled for any low voltage signals (limits, ESTOP, etc) and probably for the motor cabling as well. Make sure you have good grounding in your enclosure (including the enclosure itself.

I'm a mill and lathe guy, so a bit less experience with plasma, however I think you would be connecting to whatever port allows remote operation of the plasma unit (maybe the footswitch port?). You'd probably want a general purpose control relay. 



			https://www.automationdirect.com/adc/shopping/catalog/relays_-z-_timers/electro-mechanical_relays/square_-z-_cube_relays,_plug-in,_3a_-_15a_(78x-z-_qxx-z-h78x_series)
		


Here is one option. I'd get probably a 5 or 10A contact rating. Make sure to get the mating socket if you go with one of these. Industry uses 24V for control pretty exclusively, so you are going to have a hard time finding a 5V relay. If you need one, Amazon and the arduino community might be your answer.






						Amazon.com: JBtek 8 Channel DC 5V Relay Module for Arduino Raspberry Pi DSP AVR PIC ARM: Computers & Accessories
					

Buy JBtek 8 Channel DC 5V Relay Module for Arduino Raspberry Pi DSP AVR PIC ARM: Computer Components - Amazon.com ✓ FREE DELIVERY possible on eligible purchases



					www.amazon.com


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## jimmyferg (Apr 14, 2020)

I have a video of a dry run I would like to send to you, didn't want to post it public just yet.


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