[NuB_CNC]

This is a super newbie question and I apologize if I missed something somewhere. I've tried to search the internet and am not really finding what I'm wondering. My question has to do with how a work piece is positioned and how the CNC knows to follow an edge.

Example: Say I want to do an engraving or v-carve on a cabinet door. What keeps it so that the v-carving is straight and not going at some weird angle? Does the operator have to square the work piece to the gantry with every setup? My initial thinking was so, but then I got wondering if it was more of a function of homing.... After you set your X0Y0, do you then go to the limit of your work piece and set an X max and then a Y max?

I went to the production floor at work and watched our CNC's operate, but they simply use a system of pins to locate the part in the same orientation and position every time.

[Biggs427]

There are various ways to do it.

When I need to place a part I fix a MDF part that I machine square.

Then I make certain that the X0Y0 of the working coordinates is the inside corner of the jig.

[ynnek]

Well, how I simplified this, to standardize my stock size in my cam software. I use Turbocad, Fusion 360, & sometimes AlibreCAM. This works for me in all programs. I mostly work with 48 x 48 sheets, 1/2 sheets, of 3/4" HDPE. Mt platform is 48 x 48. So my CAM template shows this. Regardless if I choose to put on a smaller piece, or a scrap piece with an area I can work in, my CAD/CAM shows my working material boundaries as 48 x 48, with 0, 0, 0 being in the southwest corner.

[ger21]

Does the operator have to square the work piece to the gantry with every setup?

The simple answer is yes, you need to place the work so that it is square to the machine, if the part is already cut to size.

I'm used to working with machines with pop up pins, so I work in a similar fashion. I have a permanent X and Y fence on my machine, that is machined after homing the machine. So all I do is turn on the machine, home it, and place the part in the corner against the fence, and it's ready to go. Similar to what Biggs does.

[NuB_CNC]

The simple answer is yes, you need to place the work so that it is square to the machine, if the part is already cut to size.

I'm used to working with machines with pop up pins, so I work in a similar fashion. I have a permanent X and Y fence on my machine, that is machined after homing the machine. So all I do is turn on the machine, home it, and place the part in the corner against the fence, and it's ready to go. Similar to what Biggs does.

Excellent, thanks for the replies and pictures guys! I figured it must be one of those two things, but the YouTube videos I've watched never seem to show that or really go through projects where the piece is already cut to size. I'm very familiar with nesting functions with lasers and plasma cutters, but have never really been involved in setting up the machines.