Centroid Community CNC Support Forum

]I am in the process of converting my DYI plasma cutter to an Acorn controller and plasma controller and I have a question about homing switches.

In all the drawing I see the all the homing switches are connected in series (see attached image). This doesn't make sense to me. Shouldn't each be connected to it's own input so the controller can stop the affected motor? I guess the same might be true for limit switches as well.

Any help in understanding would be appreciated.

Tom

CNC12 only moves one axis at a time to the home position. Once homeall is triggered it assumes the axis it was moving is the switch that hit. It then backs off the switch to clear and sets that axix to zero. Then it moves on to the next axis. Hope that helps.

Mark

Thanks for the reply Mark,

That makes sense but raises another question.

If the system has software controlled paired axis and 2 home switches how does the controller know which motor has actuated it's particular switch?

Also, as far as limit switches. Does the system ever activate 2 axis at once to go to a given position (as my machine currently does) or is it a single motor at a time? If it's a single motor at a time then I can understand it but if it's more than one at a time it must mean you are not alerted to which axis has hit it's limit switch.

Again, thanks for the help.

Tom

Follow this document closely. https://www.centroidcnc.com/centroid_di ... _guide.pdf

I'm going through the same thing but a little ahead of you. When you have paired axis, 2 and 4 in my case, the slave axis home will be on a different input. The others will be wired in series like you have now. Pages 7 - 11, 16, and 21 of the document above gives you all the details.

Agreed, follow that manual to the letter and it'll work perfect every time. No need for limit switches, just use the soft limits, they simply work. Wire three home switches to input 1 (if possible) and the slave axis home switch into input 2. Make sure you have the Y home switches off set as the slave has to trip first. Again, this is all in the axis pairing and auto squaring manual.

That said I'm not sure you even need to worry about auto squaring with such a narrow X axis. Does the frame really twist? I have auto squaring on a router gantry that is nearly 7 feet wide and it's needed. My cnc plasma table is 5x10 and I dont use auto squaring on it and never had any issues. Just food for thought, you may be over thinking this and only need 3 home switches with simple homing.

Thanks everyone,

That answers my questions and I'm ready to proceed.

Is it to hopeful that I'll be able to do it without ever coming here with another question? Time will tell.

Thanks again,

Tom

How about turning this into a build thread and post some progress pictures?

TAS99 wrote: ↑Fri Jul 22, 2022 6:21 pm Thanks everyone,

That answers my questions and I'm ready to proceed.

Is it to hopeful that I'll be able to do it without ever coming here with another question? Time will tell.

Thanks again,

Tom

Dont be silly Tom, there's always gonna another question.

The auto squaring can be tricky if not set up properly but once it is is just works. And yes, do post more pics as you proceed.