I’m really starting to lose patience with this printer! - when it works, it works great (I’ve been printing ABS household stuff most of today) but it took about 4 hours of fiddling to get it going after the last power-off, with at least one dismantle of the extruder. But now it’s REALLY annoyed me by damaging the bed - I’d removed the build plate to let a print cool to release, and the printer homed, but somehow had the Z axis a good three or four mm above zero, so it did this to the soft magnet layer on the bed:
I keep thinking I should send it back, but I think I’ve left it too long (and also, I’m a patient person by nature, and don’t want the hassle and confrontation) so I guess I’m stuck with it, so I’ll keep working on trying to make it reliable.
I had the same on my Qidi printer when I accidently presswed home without the print bed inserted.
The homing sensors are looking for the metal on print plate and if you remove the plate it’s using the alu metal below the magnetic rubber surface as a reference!
Yes without the PEI plate it has to find metal somewhere else so gouges the magnet. Put the plate back on after cleaning up the gouge to make it flat and it should be ok again.
I have a Kobra3 sized build plate on order for the Q1Pro, might need some fettling to fit, and a couple for the smaller Enders. They don’t seem to make one big enough for my 3 larger format machines.
I’ve been puzzled by the replies suggesting the bed sensor in the nozzle is detecting metal - I thought it was a strain guage, which simply measures force on the nozzle, from contact with anything solid (metal or otherwise). I was thinking about this when I watched my printer homing just now, with a small length of extruded plastic solidified on the nozzle (about 10mm protruding). When Z homing, the bed raised 'till it just touched the tip of the extruded plastic, then stopped (so the Z level on the bed was 10mm higher than it should have been) so this confirms to me that the Z homing bed detection is definitely strain based, rather than metal detecting. So, our printers should detect the “soft magnetic sticker” on the bed if we mistakenly home Z with the build plate absent (although NOT recommended ) - that layer is very soft (as I discovered) but it should be sufficient to trigger the strain guage on the nozzle, as in my case the pressure needed wasn’t even enough to dislodge a length of oozed extruded plastic.
The range covers strain gages with nominal resistances of 120, 350, 600 and 700 ohms . The strain sensitivity k of a strain gage is the proportionality factor between the relative change of the resistance. Strain sensitivity is a figure without dimension and is generally called gage factor.
Adhesive Selection: The adhesive used to bond the strain gage to the material needs to be suitable for the softness of the substrate. Softer materials may deform more easily, so a flexible adhesive is often necessary.
Gauge Sensitivity: Softer materials typically experience larger deformations compared to harder ones. Therefore, you might need strain gages with higher sensitivity (or a different gage factor) to accurately measure the strain.
Surface Preparation: Proper surface preparation is crucial to ensure the strain gage adheres well and provides accurate measurements. Softer materials can sometimes be more challenging to prep without causing damage.
Measurement Range: Ensure that the strain gage can handle the expected strain levels, as softer materials can undergo greater elongation.
thats wat my ai have found online for this problem. the magnetic sheet deforms and dont push back enough.
Note not all K2 + are exactly the same. Unsure by how much they vary. I’ve seen pictures of extruder gears with green dots on them for visual indication of rotation, but mine doesn’t have those dots. Had to use a marker.
Biqu does not make them for the K2… yet. I have an email into them and response back that the request from this forum for K2 Cryogrip plates is with Biqu marketing. I will post to this forum if and when there is news of availability.
Brutal. If it is any consolation I and many others on seeing this will never leave the build zone unplated. Now I we can all justify getting a spare plate and printing out a quick draw holder for it.
Agreed - I ordered a “spare” build plate with my printer (there was a small discount when including with the initial printer order) as these build plates are only single-sided and it’s easy for a printer to suddenly destroy a PEI layer (as some on this forum have seen )
) - that layer is very soft (as I discovered) but it should be sufficient to trigger the strain guage on the nozzle, as in my case the pressure needed wasn’t even enough to dislodge a length of oozed extruded plastic.
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