Not sure where I'm messing up

After a long, but good day in the shop getting some work done I decided to play around some more with the Shapeoko. I have been trying to get the machine dialed in, and decided it was time to put in a little work to do so. Using some scrap MDF, I Started out by cutting a 4.0 inch square and taking some measurements. The Top of the Y axis comes out as 3.9435, while the bottom of the Y axis comes out at 3.9390. The left of the X axis is 3.9625, while the right is at 3.9610. Close to where I want to be, but not quite there yet. So I set up four slots in CC. I set them up to be 1 inch apart and 1 inch long. One set for Y axis, and one set for X axis. The Y axis slots measured out as 1.2395 at the top, and 1.2340 at the bottom. The distance between them came out at 0.7190 top, and 0.7195 at the bottom. I forgot to account for the #201 mill in my settings so I figure those not being a full inch apart shouldn’t be surprising. The X axis slots measured out at 1.2435 for the left and 1.2410 for the right. The distance between them for the left side was 0.7520, and the right was 0.7405. I have no idea if I should be looking at trying to re-square the entire machine again, or concentrate on only a certain area? Should I be looking at my belts/ V wheels? To be completely honest I have no idea what I have done or not done, only that I’ve done it, to be getting these results. Lol. I have been reading though the forum, but not sure what I should be looking for. Any help and advice would be greatly appreciated. If I need to post any photos of the machine I will be happy to do so. Thanks.

Start from the larger parts, working on square, then work down to the smaller parts.

For some reason, the instructions for squaring the machine were left out of the XL assembly instructions (but for some reason, these aren’t linked from the main site). They are repeated at:

Once the machine is square (or as square as one cares to make it — there is a point of diminishing returns, and it will run true to itself), then one can determine the belt calibration — this is best done by cutting small pockets and measuring pairs of them edge-to-edge as noted in:

Once that is dialed in, then one can determine effective endmill diameter (which is actual endmill diameter plus runout x2) — cut some slots as you noted and calculate the diameter as an average, or cut the diamond-circle-square test as noted at:

(measuring the steps in that will also allow one to dial in the Z-axis)

Should the belt stretch calibration instructions maybe be added to the wiki calibration page? Then the necessary steps are all in one place. (Full disclosure: I don’t have a Shapeoko – got a Nomad – but am thinking about getting one. )

Please see:

I think I will start with looking at the squaring of the machince just to double check, as well as making sure again that everything is tight. Then I will start looking at belt-stretch. Thanks!
I dont know if this has anything to do with calibration, and I know about the stutter when jogging a long ways. When I am setting up work piece zero for what ever I am playing with, I fast jog to get to the general area, then slow things down. This is were things get intresting. Lets say I set movement to 1.0mm and using the mouse move the X axis three times. Two of them will be fine, but the third is like I clicked the button 2 or 3 times. Z axis does the same, havent really paid notice to the Y axis. Not sure if its the cheap mouse I am using or what. There are no problems or stuttering, at least that I notice, when running a job or homing. Just something that I found intresting. I thought about hooking up a dial indicator, but thought I should proabaly work my way though the other steps first and figuer out what I should be looking for, if anything.

If you can get a repeatable problem, please write it up and send it in to along w/ all of your machine particulars. We’ll look into it.

I get that with Carbide Motion 3. I think its a combination of mouse or finger action. TBH Its not something I worry about - I either click again or go back if I’ve over done it. The advice from WillAdams re setting up/calibrating seems to me to be a good thing to follow.