K40 Mirror Aligment problems

Lasers
1

Hello everyone,
Probably for a week I can’t properly align my K40 mirrors.
I used youtube guide Proper K40 Mirror Alignment Strategy - YouTube it looked promising at first :slight_smile:
I will try to explain the steps I took.

  1. I noticed that beam from the tube hits the first mirror quite high, so to not mess up with the tube I raised the mirror 1 about 4mm, now it’s dead center.

    IMG_20210323_102433
    IMG_20210323_1024331824×4000 1.98 MB
    IMG_20210323_102355
    IMG_20210323_1023554000×1824 1.72 MB

  2. the main thing from the youtube guide was when align mirror 1 to mirror 2 first align horizontal and vertical to gantry axel witch I did. Moving mirror 2 to top and back to bottom, both test shots were dead center. And also I raised mirror 2 because I raised mirror 1.

    IMG_20210323_102556
    IMG_20210323_1025564000×1824 1.99 MB

  3. Then it was the turn of mirror 3. I adjusted mirror 2 so it goes parallel with the bottom x-axis and both left test shot meets right test shot dead center than I moved to the top right and top left. The top left was in the same spot as the bottom left and right, but the top right was 2 millimeters too high.

IMG_20210323_102749 (2)
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I found that I can lift the gantry top right corner with few metal washers which I did but it didn’t make any difference.

The main problem is that beam from mirror 3 to the lens is hitting in a corner.
This image shows the laser head raised and regular height shots of the focus lens burn from the bottom of laser head.
not raised laser heads lens shot look better, but mirror3 shots are too high.

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Sorry for my English. I hope everyone will unstrand my frustration :slight_smile:

2

This is what I used with great success.
Mask M2
M2 close to user.
Fire on low power.
Adjust M1 to get the burn in center of M2
Move M2 close to M1.
Fire again.
If second burn is higher that means M2 is TOO LOW and you need RAISE M2.
Then do the left and right.

3

Your suggested guide is from the same person I used it’s just a shorter version.
And like I mentioned before M2 at both positions is dead center.

IMG_20210323_102556
IMG_20210323_1025564000×1824 1.99 MB

1 Like
4

So when firing on M2 you get a perfectly centered dot close to you and close to mirror one?
And when you move mirror 3 close/away to/from mirror 2 and fire its the diagram you made?
Another one that was great IMO.

5

Yes M2 is dead center in both positions.
M3 all test shots are in the photo below.

IMG_20210323_102749 (2)
IMG_20210323_102749 (2)1273×1258 205 KB