1 Topic by Double A

  • Double A
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Topic: How to get proper Z-offset?

Hey all,

I have been trying to get a more accurate Z-offset on my printer but Im having a difficult time.
By default, how thick should the first layer be?
Printing the first layer, the extruder seems too low, squeezing out material around the extruder and causing it to build up.  After the first layer, this issue self-corrects.  The first layer measures .24-.26mm.

I started using XYZware Open mod in an attempt to gain more control with the offset.  Line 29 says G1  Z0.350  F2700.00.
Does this mean the first layer is set to print at .35mm?  The rest of the print is set to .3mm.
I set the Z-offset in the manual control window to Z+0.3mm, did print test and did not find any change in the first layer's thickness.

The only way I could properly compensate was to manually lower the print bed with the screws.  I tried the paper technique at first, using 3 stacked pieces of paper, measuring .35mm.  I had to do some small bed adjustments during another test print, but was able to lower the bed enough so it does not plow material.  However, now my prints do not look as clean and crisp. (see attached images)

I tried bumping the extruder temperature in XYZware Open from 215 to 220, but I got similar results, and now the first layer is .2mm.
Is the bed too high, or too low or do I have the temperature set incorrectly?  Can I compensate for this in the XYZware?
Any tips would be greatly appreciated.

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2 Reply by heidkampn1

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Re: How to get proper Z-offset?

It all depends on the position of your leveling screws. What I did, was started a print, with the nozzle starting too high (rather than too low, scratching the bed or ruining the stepper motors) than I lower the offset in very small increments. The only way to actually test the offset is to start a print, you can't just home the z and test it like that. The z will move to your offsetted position after the bed and nozzle heat up. It's a process, but it is worth it to have a little more control over your printer. My offset is set to -.28 (I think) which is only helpful for my particular printer

3 Reply by heidkampn1

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Re: How to get proper Z-offset?

I'm using repetier, not xyz.. Sorry, shoulda read that more carefully

4 Reply by Double A

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Re: How to get proper Z-offset?

heidkampn1 wrote:

It all depends on the position of your leveling screws. What I did, was started a print, with the nozzle starting too high (rather than too low, scratching the bed or ruining the stepper motors) than I lower the offset in very small increments. The only way to actually test the offset is to start a print, you can't just home the z and test it like that. The z will move to your offsetted position after the bed and nozzle heat up. It's a process, but it is worth it to have a little more control over your printer. My offset is set to -.28 (I think) which is only helpful for my particular printer

As you were printing, did you make those adjustments to the bed leveling screws or with the Z-offset in the software?

I was adjusting the screws while it was on the first layer of a test print.  If I lower the bed to get the proper filament thickness, there is separation between the print beads, if I raise the bed, it tightens the gaps but becomes thinner consequently.
I was thinking increasing the extrude rate would help, so in the manual control window of XYZware Open, I set the extruder's extrude setting from 10 to 15mm, but I cant see any night and day difference.

5 Reply by heidkampn1

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Re: How to get proper Z-offset?

I don't know how open mod works, but  the first thing you want to calibrate is extrusion rate. You can find out how to do that on YouTube or Google. (Search extrusion calibration , it's too long to type out on my phone). Then i make sure the bed is level by doing the paper test. After that, if the bed is too low or high on the first layer of the print, adjust the z offset . You don't wana touch the screws because the bed itself is already level.

6 Reply by heidkampn1

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Re: How to get proper Z-offset?

You shouldn't have to adjust the extrusion rate if the extruder steps per mm is correctly calibrated. Once you do all of that, you should get a beautifully even infill

7 Reply by Double A

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Re: How to get proper Z-offset?

Thanks, I know where to start now.  I watched a quick video, and they edit the EEPROM settings, which are grayed-out for me, so I will have to tinkering to do.

8 Reply by heidkampn1

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Re: How to get proper Z-offset?

Make sure the printer is connected to the software. That might fix your greyed out issue

9 Reply by Double A

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Re: How to get proper Z-offset?

Trial and error update;
I tried reverting to the original XYZware, then reinstalling XYZware Open mod to try to clear the settings so I could edit the EEPROM, but it is still grayed out.  When I go to the manual control tab and connect the printer, both Printer Settings and EEPROM settings become grayed out.
So I think my options at this point are to sacrifice total control and go back to the stock software, or try out other 3rd party programs like slic3r.