LaserUser.com Forum (formerly RDWorksLab)

Couple of days ago i successfully aligned the mirrors from scratch, or so i thought. Russ's methods were used.

Went to cut something big today (900x600 bed) and noticed bad cuts in one corner.

Recheck:
Mirror 1 to 2 beam is dead center and parallel with Y motion.
Mirror 2 to 3 beam is also dead center and parallel to X motion on far end.
However, if i move Y all the way back my beam is HIGH ? How ?

If i turn mirror down where its high, its going to be low on near end.

Doing my head in.

Y rails not parallel to each other ? Spot on on near end, low on far end ?

Am i making sense ?

Just to clarify, a diagram of my tape pulses:

Is the bed level with the gantry? Set focus on one corner and then test the other corners.

The most likely suspect based on your results is the right side Y gantry is low at the back causing the spot to be high. Unless you have some really good straight edges and verniers then you will find it fairly hard to determine if the left side and right sides are level with each other in particular it is difficult because of the other 'junk' in the way.

Depending on how yours is made it should be fairly easy to fix. If it is built like mine as rollers on a bit of Aluminium angle then you may need to slot the rear fixing holes slightly to lift it or there may already be sufficient slop in the holes to tweak the rail up at the back and down at the front. If it is a linear bearing on a rod then use the same sort of approach to raise the rear mounting for the rod.

Is your unit level with the floor? The gantry's level could be influenced by the machine's degree of level.