Adjusting laser tube alignment

[calley]

I've been having some trouble with alignment after replacing my tube. It cuts great in the upper left hand corner, but I can't seem to adjust the mirrors right to get a good cut across the whole work area.

It sounds like I need to adjust my tube as well as my mirrors. (according to this thread: viewtopic.php?f=70&t=2696)

But this being a k40 variant, there isn't any adjustment mechanism... there were just rubber shims under the mounts and it looks like I'm just supposed to add or subtract from those.

Anyone have a good recommendation for how to adjust the mounts? Suggestions on what material to use, etc...

[Tech_Marco]

See my post and it may help

viewtopic.php?f=47&t=2834

Marco

[calley]

Thanks Marco, very good info to have. After reading your guide and going through the process of all this tuning, I have a few things to add to that that may also be of help to others.

First... you mentioned it somewhere, but it should be at the top... use aluminum foil and masking tape for target practice. That keeps the mirrors from getting gunked up with smokey glue resin.

The biggest issue I had was adjusting the laser tube itself. I could get things tuned great with the mirrors, but because my tube was skewed, it was making all the adjustments skewed from one side of the gantry to the other. so comparing from top-left to top-right there was quite a bit of variance I couldn’t work out with the mirrors.

The k40 doesn't offer much for adjusting the tube it self… looks like a rubber pad was added to raise the tune a little from their original design. Otherwise the mount had no adjustment to it at all. That and my new replacement tube seemed to be slightly smaller than the original.

So I made a quick adjustment mechanism that I could cut in the small area I had tuned in. It raised the tube a few mm and allows me to move the front and back of the tube independently.

The vertical adjustment was my first idea and the easiest to implement. Its just a crescent ring you turn to raise or lower the tube. Not very precise, but easy to make and install. If you only have issues with the vertical tune of your laser, start with these... just loosen the mounts first.

The horizontal adjustment was much more complex, but I needed some way make it stay after I adjusted it.

I'll post some pictures for now... if anyone is interested, let me know and I'll post the dwg files too.

[Tech_Marco]

I don't recommend to use any aluminum foil because there is a lot of reflection from the aluminum which is worst for CO2 laser to be aborted. That's why we have hard time to cut aluminum. I used masking tape or Post-it to do the job

Marco

[Armoth1]

Hi Calley,

I seem to have the same problem that you had, great results close to starting point which diminishes the further I go... Cant seem to get the alignment right, each time I do the smaller adjustments for further out from X,Y its completely out when going back to "0"

Can you post the dwg files for your tube adjustment modifications please?