Warped / shifting layers

[vachonworks]

Hi there, this may have been covered before
But I'm getting a warped diagonal  shift in my prints 
These sometimes happen 10mm into a print or higher 
I've had this problem on all prints 

Sometimes it's a shift horizontal or staggered shift 

I have ordered now film too

No amount of angle change helps 

My suspicion is a faulty z axis screw or moving screen?

im going to take the thing apart tongith and investigate

[cliffyk]

What resin are you using?

What exposure and other settings?

What is the ambient temperature in your workspace?

[vachonworks]

I have fixed the issue, 

It was the tension of the z axis rail.

I removed the screw rod and the z axis on the rails was so tight it was binding causing the motor to skip a few micro steps 

This has been like it from factory setup.

Pretty shocked to find how badly these are assembled.

The tension design for the roller needs a design improvement which I will do next week

The bearing centre bushing needs to bolt directly to the off centre piece not to the main bracket piece.

This causes setup rather difficult compare to how it could be done

Because it was happening at regular intervals I thought it may have been a mechanical issue not a print setting issues.

Z axis now glides up and down with no xy wobble or binding issues. 



Thanks for your replys

[cliffyk]

I will have to disassemble mine to check this. I have no printing issues--however these units are made to meet a price point and like most contemporary manufactured goods the customer is the final Q.C.

[vachonworks]

I will have to disassemble mine to check this. I have no printing issues--however these units are made to meet a price point and like most contemporary manufactured goods the customer is the final Q.C.

so when i checked the trave, it was difficult to move, ive built a few cnc machines and instantly knew this was wrong.

removing the unit was difficult, soon as i got it past half way of the rail it popped off due to the pressure.

attached is a pic of the part that has an off centre thread for the bearing bolt.

there is a small grub screw to help fix the peice in place.

use hot air on all sides to undo the bearing bolt as it is has some sort of glue on the thread, its not thread lock, probably cheep glue.

once undone,

add thread lock to the bolt after cleaning, tighten the bolt back in but not too tight as the off centre peice will not turn properly,
slide the piece back on the rails
using long nose plyers turn the piece till it is a goo fit but slides nicely up and down the rails.
tighter the grub screw but make sure the off centre piece does not turn.
then remove the whole thing,
tighten the bearing bolt up
re-attatch to the x axis arm
then slide back on

rather backwards way of doing things because of the design.
ideally the bearing needs to attach directly to the off centre peice with clearance from the other piece.

[cliffyk]

This fellow from the UK has made available a completely redesign Z-axis tower for the Mars and some other printers.

It look quite nicely done, and reasonably priced at £87.50 (111.35 US$) for my "Silver" Mars (serial # M20Silver20200401), plus £26.00 shipping for £113.5 ($144.43 US$) total--nice design, just now ordered one.









He also offers a 250 mm version (increases Z-Axis travel to 250 mm) for £105. This requires modification of the Z-Axis lead screw so as to install a new longer screw. I have yet to utilixe the 170 mm capacity of my Mars and did not feel the added £17.5 (22.27 US$) was worth it to me--its going to be difficult enough to explain $144.43 tp SWMBO.

I feel for those poor UK an EU blokes, having to add 20% VAT...