Raise Z start - K8800

I want to raise Z direction a few layers from the calibrated zero point, for all printouts. How to do that?

I’m not sure if this helps with the first-layer-being-too-thin issue, would be good to know if that’s possible/recommended!

This seems to be the cause of a lot of people’s issues - even when prints are successful, this is a cause of destroying the BuildTak surface

Can we get some support here please @Support_Team? Thanks!

Follow the callibration procedure in the manual.

If the potentiometer of the sensors under the glass plate is set to be not sensitive the heigth of the startpoint is low. If the potentiometer of the sensors is set to be more sensitive the heigth shall be higher.

A good callibration and maintenance of the vertex (oil the rods, clean the buildtak and lubricate with PTFE the magnets) is key to deliver constant good quality prints.

Again, thank you for yout input @Franklin, but I have taken all of these steps and understand your points. I’m beginning to think my unit is faulty - print head crashes always on the lower-left side, and the first-layer-too-thin-issue is also always on the lower left

Hello Wamwam,

May problem with the Piezo’s.

  • Test the piezo sensors separately. Remove the print bed (glass) from the sensors. Place the trim potentiometer “sensitivity setting piezo” in the middle position. Then tap onto the black pad of the piezo sensors with two fingers. Once soft, and twice a little bit harder. Check whether the red LED lights up each time. Do this for every piezo. If the LED does not light up or is irregular with respect to the other piezo sensors, something is wrong with the piezo sensor(s). If so, it must be replaced (or more).
    spare piezo’s: PIEZO SENSOR SPARE PART SET FOR VERTEX DELTA 3D PRINTER - 3 pcs - Whadda

Check also these things step by step. 2. 3D Print(er) problems (whadda.com)

  • Do not use too much oil on the rods for the copper bushings. Too many results also into problems. 2 drops oil is sufficient. if necessary, first clean the rods thoroughly with a little bit acetone.
  • Check the vertical sleds for their width: The sleds => the gray parts that are clamped onto the copper bushings. Normally this part must have a width of 72mm. “At the 1st production this part was 71 mm, which is not correct (removed from the mold too early => too much shrinkage on the part).”
    If they are 71 mm or smaller, they must be replaced with new ones. You can request this as a spare part via our ticket system => [https://customercare.velleman.eu/
    Also make sure that the zip-ties are very very tight!

image

  • Check whether the edge of the “Buildtak” sticker (that is glued to the printbed glass) is cut off. This excess edge must be cut off!

  • Make sure the bed is not pinched by the 3 grey alignment studs. It should fit with a bit of clearance so the calibration routine can nudge the bed slightly. If however (due to manufacturing tolerances) the bed is pinched tightly between these studs, scrape a small amount of plastic from 1 of these studs until the bed fits loosely.

  • Check if the belt tension is not too loose. It must be the same for every axis (X, Y & Z). Tighten it as tightly as possible.

image

  • Check whether the end stops are mounted at the correct distance from the roller bearings. The distance is 0.5 cm. Check out the picture below for clarity.

  • Check whether the bolts (magnetic cups) at the end of the diagonal rods are screwed tightly. This MUST be very tight.
    It often happens that bolts (magnetic cups) are too loose on the end of the rods. Or not tightened enough. Check if the 2 bolts at the end of the 6 x DIAGONAL RODS are tight enough. If this is not the case, use 2 Allen keys to tighten these bolts (magnetic cups).

  • Every time the printer is moved or the printhead is manipulated (printhead reconnect) => Calibrate the 3D printer again! Even if the printer does not calibrate correctly: (crashing in print bed, 1st layer not correct during printing, faltering noise during calibration or bed leveling). Check the above tips and adjust where necessary until ok. + recalibrate after each change. Correct calibration method see below.

Go to menu, Vertex Calibration:

  1. AUTO HOME (home all axes - end stop determination).
  2. CALIBRATE HEIGHT (height determination)
  3. AUTO CALIBRATE

If the display shows ok, the printer will be out of the Calibration menu.

  1. Then go to SETTINGS to tap STORE SETTINGS.
    Press the button for 2 seconds, you will hear feedback of the buzzer several times. => Settings has been saved in the EEPROM memory.

Best Regards,
Velleman Support

  • Test the piezo sensors :white_check_mark:
  • Do not use too much oil on the rods for the copper bushings :white_check_mark:
  • Check the vertical sleds for their width, make sure that the zip-ties are very very tight :white_check_mark:
  • Check whether the edge of the “Buildtak” sticker (that is glued to the printbed glass) is cut off. :white_check_mark:
  • Make sure the bed is not pinched by the 3 grey alignment studs✅
  • Check if the belt tension is not too loose. Tighten it as tightly as possible.:white_check_mark:
  • Check whether the end stops are mounted at the correct distance from the roller bearings✅
  • Check whether the bolts (magnetic cups) at the end of the diagonal rods are screwed tightly✅
  • Check if the 2 bolts at the end of the 6 x DIAGONAL RODS are tight enough✅
  1. AUTO HOME (home all axes - end stop determination).:white_check_mark:
  2. CALIBRATE HEIGHT (height determination):white_check_mark:
  3. AUTO CALIBRATE :x: Print head crashed into bed

@VEL450 Thanks, but I’m still having trouble after all of this. What else can I try?

I’m going to try and upgrade the firmware as a last resort

Turns out my issues were nothing to do with calibration/mechanics of the printer, and all to do with the firmware version. See my post about this here!

@Support_Team, you might like to know about this