Calibration


Projector (XY) Calibration

  1. Download the calibration grid

    1. http://b9creator.com/downloads/CalibrateGrid.pdf
    2. Print it! Make sure to disable "Fit to Page".
    3. Measure your print to make sure it is correct.
    4. Cut out the correct size (50, 75 or 100u are the current options).  Leave a little border around the outside grid lines.  Tip:  Leave enough to on one side to create a "tab" you can bend up 90 degrees to hold on to. This is where you choose which resolution to print at; 50 is the smallest grid, with the finest resolution, 100 makes the largest prints, but with coarser resolution. The maximum part sizes at these three resolutions are as follows;
    5.  - 50 micron XY (recommended for jewelry, small parts) 51.2mm x 38.4mm x ~200mm- 75 micron XY (recommended for small parts) 76.8mm x 57.6mm x ~200mm- 100 micron XY (for larger, lower res. parts) 102.4mm x 76.8 mm x ~200mm 
    6. Place the appropriate grid print-side-up on the bottom (floor) of the basement (vat, PDMS) on the right (shallow) side

  2. Adjust the projector distance and focus

    1. Remove the translucent plastic lens cap from the projector lens.
    2. 1.Open the cover of the B9Creator.
      1. Launch B9Creator, wait for Connected. (If you don't see this, make sure the USB cable is connected to a working USB port as well as the B9Creator, and the power cord is plugged into the side of the B9Creator.)
      2. Under File menu select Terminal utility.
      3. Select 'Find Home' to get the build table into its home (closed) position.
      4. Then (after it stops moving) Select pixel size (100, 75 or 50)
      5. Click the projector power button on the Terminal Utility screen (which says OFF, but clicking it will turn it on).
      6. THEN WAIT. Projector goes thru warmup, screens may do funny things (goes to one screen on my Mac). After warmup, it goes back to 2 screen operation with calibration grid shown.
      7. Click the "Open Shutter" button on the Terminal Utility screen to move the vat to the left, allowing the red projected grid to shine through the bottom of the vat's shallow side. You can also do this by activating one of the toggle switches on the front of the machine to your left, which are visible when the cover is opened (the other one, on the right, raises or lowers the Z axis build platform).
      8. Loosen the screws holding the projector to the back of the machine, using a large Philips-head screwdriver. Turn the knob underneath, attached to the vertical screw, to raise or lower the projector until the red projected grid is about the same size as the printed grid. The 50u grid will focus with the projector close to the top of its travel; the 100u grid will only come into focus with the projector near the bottom, while the 75u grid will come into focus somewhere in the middle.
    3. Align the paper guide and the projected grid, moving the paper as necessary. Use the two focusing rings on the projector to get the image sized correctly and in focus. If you do all this correctly, the red projected lines disappear right at the printed hardcopy grid.
    4. Re-tighten the screws on the back and turn off the projector (Current state will say ON, clicking turns it off)
    5. remove the paper(!)

 

Build-Table (Z) Calibration

How to calibrate Z without messing up your PDMS! This is where we make sure that the build table is positioned exactly right in relation to the vat's delicate PDMS rubber surface.

   Open the cover of the B9Creator.

  1. Install the build table on the arm extending from the Z axis, and loosen all 4 build table screws with a 7/64" allen wrench. 
  2. Open the Terminal Utility, in the file menu of the main B9Creator.exe software.
  3. Select "Find Home"; this will move the build table to its home position hovering over the vat, and close the window by moving the vat to your right.
  4. Using the toggle switch on the left side of the machine, move the vat all the way to your left, so that the build table is over the shallow portion of the vat and the window is open.
  5. Tell the printer to move the build table down into contact with the bottom of the vat by typing the command “g” in the "Send" window in the Terminal Utility. Press Enter.
  6. Adjust the build table to be flush with the vat's exposure side by putting light pressure downward, then tighten all 4 screws with a 7/64" allen wrench.
  7. Important! Undo the main thumb screw to detach the build table. (so we don't ruin the vat coating when we remove it)
  8. Raise the build table arm clear of the build table using the toggle switch on the right side of the machine.
  9. Reset the printer with the "Find Home" command, which moves the build table arm to  57mm or so and shoves the vat to the right.
  10. Carefully remove the build table from the vat surface and reattach it to the arm using the thumb screw.

 

Notes:

Don't fill the vat with resin while calibrating the platform, if there's resin there it won't be zeroed to the PDMS level. Also, without resin there there wouldn't be any suction.

 

Also, in the cycle settings when you're getting ready to print, set the Find Zero setting to 0 on both values, if you've calibrated your build table then it's not necessary to use the Find Zero setting.

 

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