Regular X and Y layer shift on my (very) cheap Anet clone printer

[ge_rik]

I've had my (very) cheap Anet A8 clone for about 18 months now and upgraded almost every part of it. I've also strengthened and reinforced the structure to try and overcome a consistent problem I've had since I first got it - I get regular corrugations every 1mm or so on both the X and Y axes.

I've always assumed it was because the plywood structure is a bit rickety but I'm having doubts that it is the cause:

• I've done my utmost to eliminate movement in the structure and it has made absolutely no difference
• The corrugations seem too uniform at every 1mm or so which means the structure would have to flex one way and then the other after every 10 layers
• The corrugations seem uniform on both X and Y axes

So, do you think there's some sort of bug in the firmware or am I barking up the wrong tree?

Rik
PS - I've fought shy of updating the firmware because my Z screws are actually M8 threaded rod rather than the posh stuff (I told you it was a cheap clone)

 

[PhilP]

If your lead-screws are, presumably, a coarser pitch, might there be more play in the system, causing the patterning?

Did you have to calibrate the X and Y axes, at all?

 

[ge_rik]

If your lead-screws are, presumably, a coarser pitch, might there be more play in the system, causing the patterning?

Did you have to calibrate the X and Y axes, at all?

That's a thought. I'll check to see if the corrugations coincide with one full rotation of the Z screws.

No, the printer came already calibrated.

Rik

 

[3 minutes of fame]

Agreed that the threaded rod is the most likely culprit. As it rotates, it's probably introducing a small amount of lateral movement.

If you have ever run a nut up and down some threaded bar, you may have noticed a little slack - which only disappears when you tighten the nut up against something. Lead screws are a different profile to reduce back lash and therefore there's much less slack in the system.

 

[JimmyB]

If you have ever run a nut up and down some threaded bar, you may have noticed a little slack - which only disappears when you tighten the nut up against something. Lead screws are a different profile to reduce back lash and therefore there's much less slack in the system.

Most lead screws are either square or acme form, and are of very tight tolerance.