3 Bed Scanner Questions

br7408

I am looking into purchasing the bed scanner for use with my new prototype carriage (500x500 bed). I have read that it may have difficulty with the beds with embedded magnets, but should be ok once the build plate is in place. Has anyone tried this yet to confirm?

I cannot use a BL touch because the magnets in my bed are strong enough that it skews the results.

Is there any way to modify the scanning sectors so it avoids going directly over the magnets, or simply exclude the mesh data where the magnets are located?

Also, are there any CAD files of the bed scanner components available?

Thank you for your time.

droftarts

@br7408 the scanning Z probe is not affected by magnets. I’ve asked @T3P3Tony to produce CAD files.

You can specify areas that probing skips, and this will work with BLTouch. See: https://docs.duet3d.com/en/User_manual/Connecting_hardware/Z_probe_mesh_bed#selective-probing

Ian

o_lampe

@droftarts said in 3 Bed Scanner Questions:

the scanning Z probe is not affected by magnets

It's not affected by the magnet field itself, but can you rule out it doesn't react on different permeability of the build plate versus magnet material?
AFAIK, you can get false triggers when you probe near screws, so it's a similar thing...

gloomyandy

@br7408 @droftarts The Klipper Beacon probe (which uses a similar sensor technology) mentions possible problems with powerful magnets in the bed: https://docs.beacon3d.com/faq/ I've not tested it myself with the SZP.

br7408

@droftarts Thank you. I will certainly order one then and try it out.

becky9

I use an MRW magbed with Buildtak flexplates, and the szp definitely shows the magnet positions quite prominently. I did see dc42 posts showing the magnets test on his scan with an MRW bed. I can reduce the the effect by scanning further from the bed but its still an issue. I did expect this so I'm not surprised.

I do know that a lot of spring steel sheets can vary in their magnetic qualities, that some of the previous non branded spring steel sheets that I've used don't hold a candle to the Buildtak ones.... they stick really well. I wonder if lesser plates (magnetically/ferrous wise) would be better. I need to dig out some of my old ones to try.

I also thought about stacking 2 Buildtak on the bed to see what, if any difference that makes. Need to try that too.

I also need to try the manual mesh position file to skip around the magnets (assuming that works with the szp)

x

T3P3Tony

@becky9 thanks for the feedback. The spring steel plates i tested on my toolc hanger (which has a Mandala Roseworks Bed with strong magnets on it) do not show the point magnets through. Once of those is a generic spring steal bed, the other is a Wham Bam one (quite old though, not sure when i first got it)

br7408

@T3P3Tony said in 3 Bed Scanner Questions:

@becky9 thanks for the feedback. The spring steel plates i tested on my toolc hanger (which has a Mandala Roseworks Bed with strong magnets on it) do not show the point magnets through. Once of those is a generic spring steal bed, the other is a Wham Bam one (quite old though, not sure when i first got it)

Thanks for the info. I am using the Mandala Rose Works bed with WhamBam pex sheets. Hopefully I’ll have similar experience.