Currently on the “squaring” step on building my MPCNC. First, I am very confused on why it is necessary to square the trucks (step 4, tops) on the gantry rails when the next step states to take the gantry rails back off. If the gantry rails come off, then the trucks will no longer be aligned with each other.
Second, under “Step 7- Squaring”, what effect does tightening the core clamps have on the overall machine? Wouldn’t it be more effective to square by loosening the truck clamps, making sure the trucks on x or y axis are parallel, then tightening the truck clamps back down?
Just need help understanding this further as squaring has been really confusing to me.
I think the squaring step that you’re referring to makes sure that there’s equivalent force from the bearings on opposing trucks ensuring even parallel motion with minimal drag difference. That way, the x and y axes will travel at the same rate on both truck side without coming out of square. Sure, the belts will both be pulling the opposing trucks at the same rate, but I really don’t think you want any asymmetrical friction or drag on the system if you’re looking for accuracy in your cuts.
As that calibration isn’t impacted by the removal or reinstallation of the gantry rails, you’re just installing them temporarily as a guide for the calibration but need to be removed again to install the core and once the belts are installed, you can’t perform this calibration step as the trucks won’t move freely.
You don’t have to nail this completely. The motors and dual endstops will make things square enough for the cut. These steps just make sure the plastic isn’t fighting the motors while staying square.