Welcome! Log In Create A New Profile

Advanced

Calibration Offset

Posted by Bony 
Calibration Offset
July 18, 2017 06:38PM
Hello Guys,
I have a problem with my 3D Printer BQ Hephestos 2.

I adjust the offset normaly always i have done, with a piece of paper, i´m going down until there is friction, and everything ok, the problem is when the printer start print and the offset sometimes is to hight (2/3mm) or to low (touch the base), even after i adjust the offset.
I try with the warm bed, with the cold bed, I made several hard resets and it's always the same problem, or to hight or to low.

I make a video, showing the problem...
the adjust of the offset is normal and ok, but when start priting the offset stay sometimes to high or two low (touch the base) not igual when was calibrated before.

[www.youtube.com]

Thanks.
Re: Calibration Offset
July 19, 2017 09:23AM
If it's too low or too high, so inconsistent, then it must be mechanical, something loose or slipping.


Simon.

[www.precisionpiezo.co.uk] Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters. PT1000 cartridge sensors plug straight into duet boards and others.
Published:Inventions
Re: Calibration Offset
July 19, 2017 09:24PM
Nop, i verify everything, and everything is ok.

I cant find the problem...is very boring !

i adjust the offset but when start print never is equal when adjusted.

i forgot to say i put a new inductive sensor.
Re: Calibration Offset
July 20, 2017 01:55AM
Then I'd say probably a faulty or perhaps just inaccurate inductive sensor. Try doing 30-50 probes with G30 at bed centre and recording the readings. Is the sensor inconsistent?


Simon.

[www.precisionpiezo.co.uk] Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters. PT1000 cartridge sensors plug straight into duet boards and others.
Published:Inventions
Re: Calibration Offset
July 20, 2017 08:01AM
Forgive me if this is completely wrong. I have no experience of this process. But I was confused by the video.

You seemed to home using the sensor then set the bed to nozzle gap and call this the offset. Is that the correct sequence? Offset is usually the difference between the nozzle and the sensor switching height. So it would be the distance you lower the nozzle to touch the paper + the paper thickness. I didn't see a save step either but may not be required.
Also need to check there is nothing in the start code that conflicts with these actions I.E resetting z = zero.
Seems to me you are creating a 0.2mm offset from the bed by adjusting to the paper thickness.
Sorry, only registered users may post in this forum.

Click here to login