Advised nozzle z-calibration

[robv]

Hi,

The buildtak FAQ states the following:

For setting the nozzle height (i.e. the distance between your nozzle and the BuildTak sheet) we recommend using the thickness of a standard piece of office paper (or about .1mm) for ABS and a piece of card stock (or about .2mm) for PLA. with just a little bit of friction.

While the Vertex Manual talks about different specs:

I am surprise by the (almost 2x) difference between the two settings, and my print results improved greatly when going from 0.35mm to 0.2mm when printing PLA. I am using a standard feeler gauge instead of a sheet of paper:

Any thoughts?

[raby]

0.35 mm is obviously wrong as it’s the thickness of the extruded filament ans it wouldn’t be squeezed on the bed.
0.2mm is the right height. I’m using feeler gauges too but a sheet of paper folded in 2 does the job too.
With 0.1mm on the Buildtak for ABS it sticks too much.

[biscuitlad]

0.35 was fine at the beginning, when the buildTak was fearsomely tacky! But after many prints, the buildTak is much less sticky, and I’ve had to re-calibrate to double thickness standard printer paper. Even at this, around the edges I still sometimes get poor adhesion on long / big prints. Going much closer is difficult, as the print bed itself isn’t flat, it seems to have a slight but noticeable hump in the middle which is clearly visible on the first layer.