So i have been getting used to the MPCNC for a couple weeks. Found the software I like and feel like I have a good handle on that. My question is on when i go to cut something, how do i determine where on the cnc that it will print. I built the cnc 24x24 and trying to figure out where to place the material to be cut on the cnc and that it lines up correctly. I have watched youtube, but still unsure.
You adjust the CNC coordinates so that the home point is where you need it on your material.
If you use the machine home point as 0,0 remember that you cannot cut to 0 then, because the machine will need to move into negative space by 1/2 of your tool kerf to do so. (More if you use a finishing pass.)
Depending on your choice of control board, there are different ways to specify the origin.
Most will use G92 X0Y0 to specify that the current machine position should be treated as the XY origin after you use jog commands to move the machine. I recommend that this at least one tool width away from where your homing switches trigger.
Thanks Dan. So basically, I can put the material anywhere I want as long as I define home point at the bottom left for example. I move the cnc to the bottom left of my material and start from there?
Yes. Estlcam, for example typically sets up the 0,0,0 position as the closer left top of the object to be cut. You can move this, but that is the default.
Thank you. Another question I had was, since I built it for a 24x24 to cut, i should in theory be able to cut that size material? Reason for asking, is on the left side of the machine the distance is closer to the edge than the right side. Is that expected?
Yes. The tool does not reach all 4 edges equally.
In the calculator, you input the motion limits of the machine, so if you enter 24", it means that the core can move 24" from edge to edge. The actual cutting limit will be 2Ă— the tool kerf less than that, so if you use a 1/8" tool, you will be able to cut 23 3/4" width. Again, you have to add any allowance for a finishing pass to that as well.
got it, thanks Dan
When we had that question before we settled on the saying:
Home is where your part is. 
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I have been doing a big run of plywood circles for crafting I have stops setup it only took me a few resets to write down the coordinates of the center of the work. Now when I start a batch I home xy to square the gantry then jog to 311,283.5 find the top of the material and G92 xyz raise up the bit start the router and press go. I only have another 50 (at least) to go.
“Home is where your part is” is getting filed that’s awsome
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