For quite some time I have been cutting boards no bigger than 10 x 14 inches. Now I have a warped piece of MDF that about 36 x 36 inches and I’m not sure my machine can cut all of that. What I’d like to know is if the following method is correct to determine the max distances: rapid position to the south west, manually move the router further as far to the west it will go, place a point on the wood, rapid position to the south east, place a point on the wood, measure the distance between the two points to find out the maximum X distance. Rapid position to the north west, manually move the router as far to the north as it will go, place a point of the wood, rapid position to the south west, place a point, measure the distance between the two points to find the maximum Y distance. Correct?
The maximum working area for an XXL machine is specified at 33" x 33" for an SO4/Pro.
That’s an estimate, and depending on what you are trying to do, and the size of the tool in question that can be larger or smaller.
Along the Y-axis one can increase this by tiling (but note that the working area includes the overhang cutting area at the front of the machine), but the 36" along the X-axis will fit w/in the 38" or so the MDF filler strips support, but you won’t be able to cut across all of it.
My inclination would be to drop the MDF on the machine and jog around and mark in pencil to get an idea of whether or no this will work for your needs.
To verify you can cut all 33 inches jog to the far left side and set X to zero. Then jog all the way to the left and see the distance. Also jog to the extreme front and set Y to zero and jog to the back and verify your distance. The newer machines do not cut as far off the front of the machine as the SO3 did.
So if you cannot get the 33 x 33 you can change the configuration and increase the distance. Just dont increase it so much that you hit the mechanical stops.
If you can cut 33 x 33 then mark the back limit and set your material on that mark. If you set the piece up too close to the front or one side you will get missed steps when the machine hits the mechanical limits.
There is a new tiling feature I have not tried yet. However today I cut a piece of lumber that was 3.5" by 48 with a vcarve of some text. I made two jobs. One 3.5 X 28" and measured 28 inches from the end of the board and put a piece of painters tape. Then after the first job cut I moved the piece and used the edge of the tape to set X and Y zero. I did not have to reset Z zero because it was the same board. So maybe you could cut the piece in two jobs that slightly overlap or try the new tiling feature.
The job as the first half toolpath disabled. The first tool path job set up was 3.5" x 28" and the second job was 3.5" x 20". I did not bother to save the first job and just modified the first job and saved it. This job will not be repeated.
This is just the second half of the job but the first half was done the same way. My board was sticking out the back of the machine on the first half.
The machine already sets the right & back physical limits to 0,0
Just click on the word “Position” and the readout displays machine coordinates
It should say -0.197 (-5mm). That’s the backoff from the hard 0,0
Now rapid to SW until the axes physical limits. Look at the readout. Ignore the negative signs & that’s your size.
Without a tool in the spindle rapid Z down until it stops. Now the readout is your whole cutting envelope
I wrote those numbers on the front of my enclosure with a sharpie for reference
To expand on that, it moves to that position as determined by homing switch location/sensing distance, then it moves in by the pull-off distance set as a parameter in Grbl — you can slightly increase your cutting area by reducing this parameter.
I haven’t had to adjust the backoff. It backs off to -0.197 in all 3 axes, but I can still cut to 0.0, although I usually keep it at 0.010 or more to avoid the limit switches
I’d like to follow up by asking where the beginning of those 33 inches is. Is it at the south west rapid position point or as far to the left as the machine will go. Similarly, how do I map out the North South constraints?
Will: Regarding surfacing, I can see that the low point in my wood is at the center of my wood and that the high point at the south west. If I take a Z reading at each of those two points can those readings be converted to distances so that I can figure out how much material needs to be removed?