MYCNC setup for parallel gap battery spot welder

Hi Guys and Gals,

I am interesting it setting up an air actuated parallel gap spot welder head on a CNC system so I can automatically weld the cell connecting nickel strips or plates to 18650 eBike battery packs.

I know I need the hardware and the electronics, but what I am wondering is what software and I going to use to 1. create a map of where I want the weld head to stop, 2. what software will tell the weld head when it is stopped to do a weld, etc.

Attached is a battery pack that is in the processed of being hand welded. Also attached is an sample of a popular parallel gap spot weld head that is air actuated.

SMS Text 519-636-6636


hardware part of the task depends on how heavy is that device and how much force it should apply to the point when it welds
as example more then 2kg tool is too heavy for mpcnc and probably lowrider should be used.

software part has a lot of variants. 2 examples:

  • you may write a script which will have array of points and generates gcode. it could be JavaScript, Lua, Python, whatever you like.
  • you may use Fusion 360 to design a sketch with points. then use drill cycle in cam module to handle you points. in a post processor (it’s JavaScript) you can customize onCyclePoint handler to output gcode you need for a welding point.
    for control use device (turn on/turn off) you can use “M42 P{pin} S{pwm}” command or any way that people use to connect a laser head.
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Ok, let me process this information and do some more research and I will get back to your. Thank you very much for your time and your response.


It’s a pretty simple 2D design, so use a drawing program like Inkscape to place the spots in the appropriate grid, then convert that to gcode with EstlCAM. Fusion 360 is a lot more complex than you need.

I can’t agree. He need gcode which will move tool to each point, then move down, then somehow make welding, then move up and so on. I have no idea how estlcam could help here

It’s a spot welder, easy peasy. Put the welder on a spring, like the plasma table guys are doing. At the top of the spring stop, but a pressure switch. So the welder moved down, makes contact, the gantry continues to move down a touch, and triggers the welder, pop! Welded tab.

So you want say that from cnc side for this device only movements required. The device makes impulse of current itself, after you push it enough? No need to explicitly press a button (switch relay, etc)?

Hmm. May be you know better. But anyway it depends on a device. Whenever you will need a custom action at the bottom of “hole” that a device could do itself you will need custom gcode and as result you need additional support from cam side.

Hi! Did you ever figure it out? Im trying to build something similar, with gcode and opensource CNC frame. My spot welder supports automatic welding on contact so the welding part would be easy.

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