Ripples on straight walls

[I_am_me]

Hi everyone,

I have a Prusa i3 clone that I managed to get working quite right but there is one problem that I can’t fix : On any straight walls I print I get weird vertical ripples

1. Things I know

• It is not due to infill poking through as it happens even on hollow prints
• I have no problem what so ever with organic shapes
• My X axis belt might not be the tightest of all be it’s pretty good and my Y axis belt is perfectly tight yet I have this problem on both axes
• This happens even on straight walls at a 45° angle from the axes

2. Things I have tried

• Lowering the acceleration (from 1000mm/s^2 to 200mm/s^2)
• Lowering the jerk setting to 1/5 of the print speed (was at 20 before that)
• Augmenting the print speed as I thought it might be due to the way the extruder deposits the plastic (drops - moves - drops - moves - drops - …)

All of the things I tried changed nothing to my problem, the only thing that changed was the pattern of the vertical lines.

So, if any of you have a clue on what could be causing this issue I would be more than happy if you cloud post a comment.

Thanks

[Morten]

It could be excentricity of, or a burr or some debris sitting on one of the teeth of the timing wheels of you x- or y-axis; I suppose the ripples arise only along one of the directions?

[Georgi_Krastev]

My toughts exactly, someting wrong withe the pulleys or their bearings.

[I_am_me]

By eccentricity do you mean having the axes not perfectly aligned ?

I’m going to check if the belts or pulleys have any debris hindering them.

The thing is ripples do happen in both directions.

[Morten]

It is eccentric if the shape of the teeth of the timing pulley is not circular, or if it’s outer perimeter is not concetric with the axle-hole. By both directions, do you mean in the y- and x-directions or do you mean both forward and backwards in the, say, x-direction? If it is both in the x- and y-directions, I would say that you should check all timing belt pulleys and idlers.

[I_am_me]

Ok, then it is not eccentric. By both directions I mean X and Y (going forward or backwards does nothing different for this problem), I checked my pulleys and belts and there is nothing blocking them. As I said in the description my X axis belt is not the tightest so it could be one of the causes but my Y axis belt is perfectly tight yet I have ripples on both axes.

[Morten]

Except for eccentricity or debris, I find it hard to come up with another explanation. There could be the effect of ripples after a corner when you run with very low acceleration or jerk, while also running with high speeds. Then you would see ripples wearing off further from the corner, whereas your images indicate constant ripples along the vertical faces. That suggests that they are cause by some geometric/mechanical, rather than some dynamics. However, try go at low speed with high acceleration and high jerk, and see if that changes anything; increasing or decreasing the ripples you observe.

[Raymond_Barrett]

Hi, It will not be the belts, unless they are too tight. Look on ‘youtube’ for hints on how to calibrate Extruder properly, make sure everything is square and level. It will be Temperature, Inconsistent extrusion or Mechanical problems. Go to ‘Simplify3D’ website and look for the “print Quality trouble shooting guide” lots of help here for many common faults. I bought a HicTop i3 just under a year ago, quality was ok but not perfect. with a bit of updating, converting to auto levelling and changing slicer software to Simplify3d my prints now are perfect. Can’t say its been easy, but enjoyable, and at 68 I have learned a lot. Biggest problem now is remembering it all (ha ha).

[broncosis]

I have had this same issue I would look for a set of z axis wobble isolators on thingiverse They completely solved this for me What’s probably happening is your z threaded rod is not perfectly straight and its pushing your carriage one way or the other every layer

[Morten]

Seeing broncosis comment made me think again. The first thought I had was that this was a z-axis wobble. I have had severe z-axis wobble on my old Orca v0.3. However, I locked in on the pictures included with the original post, thinking that the objects are oriented on the print plate as on the pictures. Is this not so?

In the OP’s description, it says “vertical” ripple. Is that one where the wave-vector is vertical, which would be consistent with a z-axis wobble, or where the wave-fronts are vertically aligned, which would be consistent with x- and y-axes wobbles?

[I_am_me]

The prints are indeed oriented as they were on the build plate.

It is the wave fronts who are vertically aligned. I don’t think it is Z-wobble because I have multiple wave “points” on every layer, which together make a vertical line, Z-wobble would be happening at layer changes, not multiple times in a layer.

[I_am_me]

The thing is that I have multiple wave “points” on every layer which together make a vertical line.

[dimitriz]

Hi! i’m having exactly same problem, did you solved this?

[I_am_me]

Sadly, I did not

After looking around a bit more I have heard that putting the printer on a hard surface such has a concrete block could help but it didn’t work for me. I could also be caused by flow control issues but again, didn’t work for me.

After looking a close look at the machine during printing I’m almost certain this is caused by vibrations, either through ghosting or plain old resonance of the printer but I did not find a way to fix it.

I hope this helps you, if you find a solution that works for your problem I’d be really happy if you could let me know

[dimitriz]

Hi, thanks for the answer

i’m attaching a picture of mine, it appears to be exactly same problem…

i will make more tests, if i discover something, i report here.

thanks again

[TehEmoGurl]

I’m rather late to the party, looking up an issue im having myself and came across this. Just incase your sitll having this issue i think i know the solution. Atleast to @dimitriz anyway. I think @I_am_me 's issue could possibly be the same depending on your infill settings.

It looks to me like the infill layers are showing through at the edge where there is slightly more plastic inside so the layer lines push out the outer shell causing slight ridges. First test: Hole the part up to a strong light and see if the ripples align with the infill lines. If they do, just increase your shell thickness in your slicer. I had this issue at 2 shell layers so i increased it to 4 and my surfaces no longer get this.

Hope this helps someone!

[I_am_me]

As I said in my first post, it’s not a problem with infill. It happens even on 0% infill or vase mode.
But you’re right, for most people this kind of ‘symptoms’ are because of infill poking through.

[steveprinters29]

If you are experiencing ripples etc. in your 3D printed object, you can try out the following:

• Reduce the 3D printer vibrations by placing it on a solid surface
• Check the bearings to be smooth
• Make sure all the bolts of the equipment are tight
• Add oil to the rods of the 3D printer
• Adjust the acceleration of the firmware.

[wirlybird]

What is the print speed? What slicer?
This really looks like a mechanical issue. If it were acceleration or something like that (Ringing) it would fade quickly along the face and definitely would be very unlikely to do it on a 45 degree pass in relation to the X and Y. The first clue is the “rhythm” of the waves, they are persistent across the face.