Lens/Mirror

[Mark Taylor2]

I'm attaching a photo for this. I changed the tube and checked the alignment at mirrors 1 and 2. I put a bit paper in front of the mirror/lens head and checked that. All were dead center at both upper left corner of the cutting area and lower right corner of the cutting area (near and far). No beam out of the lens for cutting or etching. The head was loose so I re-seated it. Still no beam out. I removed the lens and put a piece of thermal paper on the underside of the top assembly (mirror part) and when I look down, I see that the burn is upper right.

I've tried spacers on the mirror opposite the burn area thinking angle of beam in = angle of beam out but no joy. I've disassembled the lens/mirror head and re-installed it several times checking everything for "square and level". Everything seems to be square and level.

Any ideas on how to fix this to get the beam centered so it will hit the center of the lens? I'm stumped.

Machine is a MicroMark Laserkniife (glorified K40) with an upgraded power supply (Automation Tech), 45W/50W tube (Lightobject) and chiller (Lightobject).


DSCF2857.jpg

[Bill George]

Did it ever work or has something been changed?

[Ron Gosnell]

Theres a couple of good articles on this site if you can find the right search terms. Pretty detailed.

[Matt McCoy]

I don't see the pic -- maybe since I'm on a tablet. If I follow you correctly, you have good alignment all the way to mirror 3, but not through the lens. If that's the case, mirror 3 will need to be adjusted to hit the center of your lens.

[Bill George]

No pictures posted even on a PC laptop seen.



Happy New Year!!

[Mark Taylor2]

Facepalm moment... photo added.

[Matt McCoy]

From the pic, I would guess the path is blocked by the nose cone. Might try a test pulse without it to see if you get a mark. Mirror 3 will need to be adjusted so the beam hits the center of the lens.

[Kev Williams]

for the life of me I can't tell what I'm looking at in that picture--can't tell if the camera is under the lens or above it? I see an oval that may be the mirror, if so, then is this a cellphone pic below the lens?

That all said, if the beam is hitting all the mirrors in the center, then the last mirror- over the lens- needs to be moved laterally (to move the beam left or right in the X axis) and/or the tilt must be adjusted (to make the beam perpendicular from top to bottom).

[Jerome Stanek]

when I got my laser I couldn't figure out why it was cutting on an angle until I checked the last mirror placement. they had the mirror to far back and to get the beam centered it had to hit the lens on an angle not straight down just had to move the mirror forward

[Mark Taylor2]

I'm starting again at the beginning of the mirror alignment. This is most puzzling is why everything lined up and looks good until I get to the final mirror.

I tried shimming the mirror and got the beam centered, then when I put the lens in, the beam shot off at angle. I'm wondering if the lens/mirror (not sure of the right word) "cart" somehow got wacked out of adjustment but I don't have any info on adjusting it nor what screws to turn.

[Kev Williams]

can you show us a few pics of the full laser head assembly?

[Mark Taylor2]

Pics are here. What I've discovered so far is that the tube sank into it's mounts due to the water. There's foam padding. So that's partly fixed it. Everything (beam wise) is where it should be until it hits mirror#3 and goes to hell in a handbasket....

Here's the pictures of the laser head. The mirror/lens is sitting below it.

DSCF2862.jpgDSCF2864.jpg

[Bill George]

Pics are here. What I've discovered so far is that the tube sank into it's mounts due to the water. There's foam padding. So that's partly fixed it. Everything (beam wise) is where it should be until it hits mirror#3 and goes to hell in a handbasket....

Here's the pictures of the laser head. The mirror/lens is sitting below it.

DSCF2862.jpgDSCF2864.jpg

Sank into the water??
The beam needs to be in the center of the mirrors verified by putting masking tape over each and finding the burn mark. The last one is the hole in the laser head on top entering the hole and then hitting the mirror. Is it centered entering the hole? If so the mirror on the back needs to have the burn mark centered and directed down the tube. Start at the tube and work forward to the laser head. Good write ups on here and on Ray Scotts website. You should not need to shim or otherwise adjust that last mirror.So a new tube was installed, is it the same height as the old one if not did you make a adjustment to correct?

[Mark Taylor2]

Not sank into the water.. into the foam mounts. I had checked the alignment when I put in the new tube and then had to wait almost a week to do any testing as I was waiting for the chiller. I got everything reset, re-centered, and the beam is almost dead center on the lens.

[Mark Taylor2]

I do believe I found the problem... the #3 mirror appears to be delaminating. I've ordered a new one. I realized that my results were inconsistent and was struggling to lock down and remove any variables in the aligning and testing. I finally noticed that the mirror front piece and the substrate were not, for a lack of a better word, aligned. If I pressed it on edge, it moved and I could get it re-centered but after handling it and testing, things shifted. I'm not sure what caused this. Heat? Minute scratches on the mirror surface? Age? Who knows.