Z Axis Artifacts - Known Issues and Fixes

Thats what I thought. Guess I'll be contacting the supplier.

 

I've contacted the supplier so hopefully I hear back soon. I could spend hours trying to correct the bow and get no where or make it worse. They weren't too expensive but they should have been straight. I'll wait to see what they say. I'm looking forward to doing the upgrade so it's annoying. Thanks Z.

 

Ziggy, thanks for your effort and very systematic approach to addressing this issue and helping us all improve our print quality.

 

Hey tess Can you help me hunt down that coupler on the internet? i slightly bent mine and the ribbing is back

 

So if overheating is the only reason to adjust the board, can i just leave it as is since i have a cooling fan blowing at it all day ?

 

Hi
first thanks to ziggy for his great work

While replacing my rods i realized that even M8 rods don't fit into the coupler (or at least mine )
M8 x 1.25 have a diameter from 7.760 to 7.972
M8 x 1 have a diameter from 7.794 to 7.974 (so this should be a bit better)
But a bit of Sellotape or Scotch tape(I guess that's the name in english) solved the problem.

The main thing i wanted to point out is that the problem is not so much the teflon tape, but the little screw that pushes against the rod. On mine this was tightened (needed to because otherwise it wouldn't fit) so i tightened this one too. But then the rod was really misaligned. (The rod itself is perfectly straight)
Now with the Sellotape / scotch tape only its almost perfect (3mm at 300mm lengths, an I thing i bended the coupler because at first i thought this was the problem)

Maybe a solution could be to print a small tube with a split, with outer diameter of 8mm and inner of 6mm (or 5.5 and then drill it properly) and use M6 threaded rods, one advantage only 1mm per turn.
Maybe i try this once.

 

So I have done a few of the list of upgrades to remove the ribbing + some others

Fix 2 - Making sure the threaded rod/nut stiction and friction is as low as possible. clean everything and use moly grease (would probably be better with a dry lube but did not have any, on my list to do)

Fix 3 - Setting the motor shaft in the coupler so it does not slip

Fix 4 - Stopping height variation due to the coupler geometry - essential. Added a bearing in each coupler

Fix 5 - Seating the threaded rod properly centered in the coupler + replaced stock with M8 rods
I also did a bed upgrade at the same time.
A significant improvement to print quality as shown in the attached photo, latest print on the left.

To do;
install some Z-rod sstabilizers
Fix 1 - Firmware Z Disable configuration change

Ziggy thanks for the detailed post and information

 

That site sucks. Cant see anything without registration.
Plus, who needs to read entire poem when all it takes is replace the rods with metric once.

Nice dog by the way.