Taz 6 Ringing/Resonance/Ghosting along the Z-axis

Greetings Tim,

Extruder’s e-steps were previously adjusted to compensate overextrusion. Currently it’s actually underextruding 5mm, see attached.
All the prints have default print settings with heated bed either at 0 or at it’s defaults. They were set to standard quick print settings with Village Plastic presset (Nozel: 240, Bed: 110). Also tried to print one benchy with IC3D Profile which has adjusted temps (Nozel: 235, Bed: 85). It printed better, yet with same artifact. Attaching image of the lead screw with printed models.

Your time is highly appreciated!



Hmm, it does line up pretty close. Take a look at your Z rods and their bearings and see if it looks like there are any gaps in the contact pattern between the inner bearing slide surface and the rods. If there is, consider popping the bearings out of the sockets, wrapping a bit of scotch tape around the body then reinserting them, being careful not to create too much pressure. It may also be that the motor allignment on the Z motor couplings or the motors themselves is slightly off. after taking a picture to record the origional position, try loosening the Z motor mount bolts on both sides, then run the z axis up and back down slowly, then re tighten the mount bolts. This can remove excess side load on the leadscrew. you can also try re adjusting the leadscrew couplings. If they are off even a few degrees, it can create excess force on the side of the leadscrew.

One thing you can also try to see if the leadscrews are indeed the cause, is to temporarily remove the upper leadscrew mount bearings and then try a print. If that noticeably improves the surface down near the bed and to the middle of the print, you may be dealing with a leadscrew that isn’t straight. I do not recommend running in that configuration permanently as there are some potential wear and deflection side effects, but it’s a good way to see if thats what is going on. You may also want to try lubricating the leadscrews with white lithium grease, as that can tend to moderate the effects somewhat.

Good evening Tim,

Attached are the photos of leadscrew bearings. They seem not to have any gap and I checked to see if there is any play, they are fine.

Could you describe in detail how to troubleshoot the leadscrew? Leadscrew mount is the one that has two bolts on each side and two bearings from each side on the z rods? Should I take out the bearings that are in attached images?

Had exact same thing going on with the first unit. Diagnosis received from support were saying faulty toolhead. Yet it clearly has pattern of these leadscrews in every print. Some prints shows it pronounced, some some not, depending on the topology of the mesh that’s being printed.

Kindly explain step by step guide on how to solely troubleshoot the threaded rods.

Thanks!
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Troubleshooting leadscrew issues is one of the most difficult aspects of tuning a 3d printer. There are a few ways you can go about it. If you have access to a granite flatness slab you can pull the leadscrew and roll it on the slab to check for bowing or warps. If that isn’t an option you can try removing the top 60877 round metal bearings to remove that constraint, or the z motor adjustments I described in the previous post. You can also try loosening the z nut mounts slightly. Another option that sometimes works is deliberately turning one of the leadscrew manually 1 half turn to try and get the threads out of phase with eachother.

Basically what you may be dealing with is a slightly bent leadscrew. Or one out of tolerance. It’s possibly moving the x axis out of true by exerting more force than the bearing Rod is exerting to keep in position. The way I fix that on a 5 series is to fit an anti wobble device. There aren’t any that fit a 6 series yet though. It could also be a leadscrew that is fine, but is being pulled out of true by a motor or a coupling, or something out if alignment on the frame.

Produced another Z resonance tower with z motors slightly loose and it amplifies the result. There is something in leadscrews structure that is causing this binding. How likely after disassembly and trouleshoot of the threaded rods, there might arrise more issues?

Thank you!

After going through Standard Warranty polices, on the 4th paragraph it indicates that disassembly or attempts to repair the product potentially voids the warranty.

Was there any resolution or improvement on this?

Follow the threads in below order:
https://forum.lulzbot.com/t/taz-6-specific-openbuilds-x-axis/3787/1
https://forum.lulzbot.com/t/adding-an-openbuilds-openrail-y-axis-to-a-taz-3-4-5/2019/1
https://forum.lulzbot.com/t/taz-6-anti-wobble-z-nut-mount/5235/1
https://forum.lulzbot.com/t/the-backbrace-project/5269/1