Big Thunder not cutting


I am cutting large sheets of 1/8 in acrylic, 48" wide. The Thunder is cutting beautifully until it gets to the bottom right corner. From reading previous talk discussions, this is possibly due to mirrors needing cleaned/adjusted. Is there anyone around that would be able to do this for me so I can continue with my cuts?


Is it not cutting at all or just not cutting all the way through?
Edit: in the corner specifically

all the way through.

I tried to refocus incase the level of the bed was slightly different, however it is now not letting me focus due to a hard stop so on the bottom right, the focus is off.

Are you using the Z axis to adjust focus?

We’d prefer adjusting the lens tube to get it closer and avoid the possibility of crashing the head into your work. It will also give you some focus adjustment even if the table is all the way up.

We’ll level the bed on the laser soon.

Because the mirrors are so far apart and the laser beam can spread more you may just not be getting the same amount of power focused into a point like you do elsewhere.

You might try isolating some of the paths in that corner to a different layer and having them run at 80% of your current power level but running twice.

Just an add on - I was cutting some 1/16" plywood Friday night on big thunder. I usually use 70%/30% with no problem. This time it was taking two passes. Location was on the LEFT side of the bed. I moved to the middle and it worked much better at cutting in one pass but it began cutting less the more to the right I moved. So mostly working well in the center. I do not use auto focus. I used the puck to manually set for vector cutting.

I’ve done approximately 6 passes in the same cut and am still not getting all the way through. I have refocused using the puck. I started using 20 speed, 65 power and am now at 10 speed 65 power.

Bottom always cuts less than top, right less than left, so bottom right cuts the least. Even if the table is perfectly level, the beam travels further between mirrors to get to bottom right, thus disperses more.

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Well the optics are clean and in alignment. It looks like someone replaced the last mirror recently, so that could’ve been the problem. We’ll level the bed soon, that should fix up the last of the issues.