Results 1 to 3 of 3

Thread: New theta Lens for Fiber Engraver

  1. #1
    Join Date
    Aug 2018
    Location
    Arizona
    Posts
    27

    New theta Lens for Fiber Engraver

    Hello. I am back.

    I purchased a new Theta lens, sized 160MM, stamped on the side, where my engraver came with one stamped with 420mm on the side, but the machine has a label that instructed me what to put into parameters (F3).

    For the new one, I am following instructions from this fine thread:

    https://sawmillcreek.org/showthread....-for-the-fiber

    I take 160MM and divide by the square root of 2, and get 113MM, so that's what I entered into F3 and also workspace. I then drew a square 113 x 113, engraved it, measured and then followed the instructions on how to enter so the square is 113MM (or so) on X and Y when engraved.

    Problem I am having is that the 113mm engraved square "bows" outward between each corner, and not sure how to adjust so it's a true square. I know in F3 one can adjust, but as I fix the X bow, the Y bow gets worse, and vice-versa. I assume this not being square will have an impact on the alignment of engraving.

    Any tips on how to adjust, or if someone who has a 160MM lens can share a screenshot of their f3, that would be great.

    IMG_20200326_164949.jpgs-l1600.jpg

  2. #2
    You need to do a full-blown alignment, below are the F3 menus you need, the main menu, and the 'red light pointer' menu which is within the "other" tab...


    You're on the right track with the bulging, it needs to be adjusted out. First thing to, draw a 3" or 80mm square, dead center it. Get some paper and pencil. Open the main menu. Now add .5 to the to the bulge adjustment on glavo1, then redlight it. Make note on your paper as to what changed, did it bulge inward, or farther out? Now do the same thing with galvo2, make note... The do the same with the angled sides and trapezoid adjustments on both galvos. Now you have a map to show you which way to make adjustments. It will help as it can get confusing. Make some preliminary adjustments until the redlighted square looks pretty good.

    This personal choice, but now is when I line up the red-light to the engraving. You need something to engrave a box on bigger than 3", and tape it down so it won't move. Focus, and engrave a box, using ONLY enough power to barely etch it. Now redlight, and make notes of about how far off the size and location is to the actual engraving, then go to the red light menu. It's pretty straightforward, you can offset the red-light in any direction. If the box isn't the right size, measure the actual engraving, then measure the red-light. From here you make adjustments in the 'size scaleX' and Y boxes, in percent, where 1=100%. Adjust up or down as needed. Within a few minutes, between placement and scale you should be able to line up the red light path dead on to the engraved path. If so, you're DONE aligning the red light

    Back to the main menu, now you want to adjust the main laser output. Simply, you need to adjust out the angles and bulges until the lines are straight and at right angles to each other, to suit you. You can do this with the red light, or engraving scraps which is better. A piece of paper's corner can be used as reference for square. Doesn't have to be exactly square at this point, just straight sides and square corners.

    Now engrave a square, any size okay just close to 4" is good. Measure the square's sides and jot down the results. Now open the main F3 menu, below "Negate" and to the right of the "Scale" box is a button, pressing that will ask you to enter the 'desired size', and the 'actual mark size', do this for both X (galvo 2) and Y (galvo 1) axis's. This will automatically change the the scale adjustments. Engrave the next box, and the measurements should now be REAL close, but probably need a bit of tweaking, which I do manually.

    And that should do it! IF your box is not engraving square to the machine or scanhead or whatever, this can be fixed with the 'angle/degree' adjustment.

    When done, re-check the red light alignment, but it should be fine. You WANT the red-light as close as possible, for basic aligning, and for the occasional 'oops' where you need to engrave again, if you're patient and the red light is accurate, you can re-engrave many times and never miss
    Last edited by Kev Williams; 03-31-2020 at 10:23 PM.
    ========================================
    ELEVEN - rotary cutter tool machines
    FOUR - CO2 lasers
    THREE- make that FOUR now - fiber lasers
    ONE - vinyl cutter
    CASmate, Corel, Gravostyle


  3. #3
    Join Date
    Aug 2018
    Location
    Arizona
    Posts
    27
    Thanks Kev. I think your screen shots will give me a good reference/starting point.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •