Square X/Y granty problem

[jeffeb3]

@Tigertom

The dimensions in the diagonals are 101,6cm and 101,7cm (measured at the upper housing corner, near to the tubes), so only 1mm difference that means lower than 0,1%, for my opinion is this really good.

The 101.6cm and 101.7cm are the diagonals of the outside frame, right?

Are the lengths of the two X sides and the two Y sides the same? The two X sides of the outside frame are both 800mm?

@Tigertom

The squaring-error is approxomately 5mm between Y0 and Y1, and 10mm between X0 and X1 (hope you understand what I mean, X=930mm, Y=800mm). This is an other world when I see the difference in the diagonals.

I don’t understand, but you haven’t wired up the motors, so I wouldn’t be too concerned yet. When you get the motors wired up, use them to draw a big rectangle, and use the measurements from that to decide how to fix it. The motors will move in lockstep (X and X2 move exactly the same distance) so you just have to start the gantry square and it will stay that way.

@Tigertom

My plan was to use only 3 stepperdrivers TB6600, and the two X- and Y-motors are in a row.

Make sure you wire them in serial and not parallel.

@Tigertom

I prepared the double-endstop-solution (mechanic, switch, cable), but I don’t like to force the mechanic over this way.

1. Moving a few mm over a 1m tube will not hurt anything. Don’t worry too much about it.
2. You can use blocks or hard stops to move the gantry square while you enable the motors. Then you only need 3 drivers.
3. You can’t auto square your frame without providing each motor it’s own driver. If it were me, I would ignore the endstops and just wire the double axis in serial. Put some clamps on each pipe so you can snug the gantry up against them when enabling the motors. You can easily get within a few mm with the clamps and over a 1m span, that is good enough for almost any job.