G29 autolevelling destruction G2S

[darkikal]

hi guys i have something similar finally g29 succes changing parametters on marlin but when i test a print after g 29 and heating the spider goes dow and touches the bed causing an emergency stop the z eight defined all in the guide defined any idea guys????

[Mark]

Try to check your X/Y/Z axis direction, sometimes the wrong direction will cause the problem.

[darkikal]

x y z are good wired cheking manually directions also good

[moriartynz]

I am not sure, but this looks like what I seem to be experiencing, namely that the G29 set of probing data seems to be creating a correction for points that are in error. My limited delve into the Geeetech Marlin firmware code shows me that the firmware uses a different method for calculating positioning after G29 is executed and there is autolevelling data available. My suspicion is that this calculation system for coordinates after auto-levelling is somehow completely wrong.

Regards
Mark

[Mark]

Try to check the probe of your spider.sometimes the probe couldn't go through the hole fluently and would get stuck by the hole, therefore the probe endstop will not trigggered. One of my customer reassembled his spider and probe, and drilled out the hole and make it freely for the probe to pass it and G29 works! Also he replaced the lock ring with a brass one to give the spring a much higher compression so it would work reliably.

[moriartynz]

Thanks Mark,

I have already replaced the lock ring with a brass one as the plastic one I was supplied with by Geeetech would not work (did not tighten). I have checked that the probe moves freely and also sprayed silicon oil through the hole for lubrication. I still have the G29 auto-levelling problem.

[Mark]

What position did you assembled the probe? it should be on the right of the spider, as the pic shows:

[rickr]

I was having this very same problem until I replaced my spider and hotends. In replacing them it cause me to really be careful about reassembly and I even took photos. The key I think was that

• I took a couple of small drill bits and drilled out the probe hole enough to make it move freely,

• then I took the round sanding tool that Geeetech sent with the kit to clean out the top end of the probe holder to ensure that there was no sticking

• and finally replaced the lock ring with a brass fitting, which I believe everyone has had to do to get this to work.

The other think is something that Geeetech support insisted that I needed to get right, otherwise the auto level would never work and that is to make sure that when you assemble the spider and you are looking at the printer front on (the LCD is closed to you, X on your left, Y on your right), the probe must be installed in front and to the right of the nozzles.

The probe MUST be on the right hand side pf the spider assembly, the nozzles will end up behind it.

QQ截图20150820175951.jpg (484.18 KiB) Viewed 15097 times

Below are a series of photos that show the way my G2S spider assembly was assembled to ensure that it worked with the G20 auto level command.

The probe MUST be on the right hand side pf the spider assembly, the nozzles will end up behind it.

QQ截图20150820175951.jpg (484.18 KiB) Viewed 15097 times

The probe MUST be on the right hand side pf the spider assembly, the nozzles will end up behind it.

QQ截图20150820175951.jpg (484.18 KiB) Viewed 15097 times

The probe MUST be on the right hand side pf the spider assembly, the nozzles will end up behind it.

QQ截图20150820175951.jpg (484.18 KiB) Viewed 15097 times

Let us all know how you go. OH Most important!!!!! When you start to set up your printer, the bench or table you set the machine on MUST BE LEVEL then start configuring your printer.

Cheers, Rick

[cmore11]

OK. I'll ask it. Why does the probe have to be mounted on the right? Yes, it has to be mounted opposite the fan, but why does it have to be mounted to the right as you look at it from the LCD?

[moriartynz]

HI Mark and Rick,

Thank you for your input. I did have the spider the wrong way round initially, but Eric (from Geeetech who sometimes posts on this forum) pointed out my error. I have subsequently reassembled the spider as shown in the attached image. The probe is on the right, the X to the left, Z at the back and Y on the right as you recommended Rick. I also widened the hole. I have not drilled it out as recommended by Mark and Rick as yet but with the silicon oil, the probe moves smoothly so I did not believe that friction was the issue.

The probe operates fine. I have a video showing my problem. https://www.youtube.com/watch?v=VMOQMlYJopk The video shows the device before I switched around my spider. The same problem happens after the spider was rotated so I have not updated the video.

Rick, was your device also trying to destroy itself mid-air like mine as shown in the video or was yours doing something different?

Regards
Mark