buckles on the surface

[GeorgB 0]

In the last week my printings have always those "buckles" on the surface.

It looks like the perimeters change slightly positions from slice to slice.

I have printed the parts weeks ago (all is fine) but now it has this unnice buckles.

I am not aware of changes on the settings.

Is that problem of the hardware? Any help is welcome!

[tommyph1208 55]

It looks a bit like the patterns you would see with underextrusion:

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#underextrusion

Are the walls solid enough and bonded tightly? (hard to tell from the picture)

Edited September 29, 2015 by Guest

[GeorgB 0]

Hello, thanks for your reply.!

Underextrusion might be a possible issue, because the toplayers could be tighter - but I did not find a solution for it.

The walls are 3 perimeters thick - that is normally quite ok.

[gr5 2,265]

Try slowing it down maybe? Try 35mm/sec. Make sure all your printing speeds (shell, infill, inner shell) are at the same speed.

It's hard to tell because it's black but it doesn't look like underextrusion to me. But hard to tell.

I would expleriment as it's printing. After you see the pattern, try slowing speed to 50% to see if it goes away. If not then try changing the temperature and let it do a few more layers and see what happens. Usually for best quality you want 20-35mm/sec and 190C to 200C.

[Labern 775]

In the picture it looks a little warped. Maybe just the angle of the picture though. Is it flat?

[GeorgB 0]

Sorry for my limited info...

I am printing with ABS (heated plate 90°,ABS 250°,2.85mm), speed 50 mm/s

the part is 80x40x15mm. I am using slic3r for slicing.

One side has more buckles than the other side.

I tried now also with 35mm/s but it made more or less no difference.

I made the parts some weeks ago with good surface (i think(?) I made no changes in settings). Tat leads me to think it has something to do with the hardware....

[shurik 87]

@GeorgB - I had something similar when Cura was directing the printer to make infill before the outer shell for each layer. In the later versions of Cura, the setting "Print infill atfer perimeters" solved the problem.

Alternatively, you might try to print colder, at 240C and slower, at 30mm/sec to see if that helps.

[tommyph1208 55]

When one side is worse than the other, it usually means that it is related to cooling...

You have a fan on one side of the printhead yes?

Is it running when you print ABS?

At what % speed?

[GeorgB 0]

@tommyph: I print without cooling. (UM2).

@shurik: In slic3r you have the option "Infill before perimeters", which is off. So the outer shell is made first..

I reduced from 50 to 35 mm/s which made no difference.

What do you think about the top level. Is it underextruded? In my opinion the top layer could be more covered. I tested some options, but was not really successful to have more material on the top level. (right now 3 solid top layer, and the top layer solid infill runs with 50% of the normal speed of 50 mm/s)

[gr5 2,265]

It's definitely a slicer issue because it's fine on the layer with the hole through it. Notice that? Those layers are perfect! then when the hole is done it starts doing it again. I don't know what the issue is. Try Cura maybe? did you try the lower temp? 240C works okay for me as long as there is zero fan! And layers not too thin else they won't melt the layer below. .2mm is good.

[gr5 2,265]

Oh - and these pictures are much better. that does *not* look like underextrusion. I don't know what that is.

[Labern 775]

It looks similar to the zebra stripe issue but to the extreme.

The 45 angle area where the part folks out on one of the photos looks good.

Have you tried printing the item on a 45 deg angle on the bed?

Wont explain the clean part where the hole is that Gr5 is talking about though.

[yellowshark 153]

Although I use Cura these days I used slic3r for some time and have never seen your problem. I would slice with Cura 15.04 and see what happens. Alternatively try it in PLA if you use that too.

If you want to post your stl file I would be happy to try it (no doubt others would too).

[GeorgB 0]

Silly question - how can I post an stl-file?

[ultiarjan 1,223]

Silly question - how can I post an stl-file?

 

just use a service like dropbox and post the link.

[GeorgB 0]

I tried the same part with Cura - it looks quite different.the stripes change postion with the speed.

Anonther issue: if you move the nozzle (UM2, of course power off) do you feel any resistances? If I move the nozle, I feel not the same resistance over the movement. In some position it goes harder compared to others...

(sorry I send this message first to the wrong entry..)

the stl file is here:

https://dl.dropboxusercontent.com/u/2958151/Bike-Flex.stl

Edited October 5, 2015 by Guest

[Labern 775]

I have noticed there are a few issues related to the small holes that run out from the center hole in layer view. I wasn't able to get it to slice them properly. I wonder if those loops are related to that.

[GeorgB 0]

I have added this to the model to increase strength in that area.

I don't think that there is a relation, because I have the same issues also on other parts.

What slicer do you use? (I could slice it in Cura and Slic3r without problems!)

[gr5 2,265]

On the center picture above - that red circle is showing "ringing". Which printer do you have? Please note this in your profile settings.

Ringing happens because the printer is moving right-to-left in that part of the photo. When the printer hits that corner hard as the print head moves in the new direction, the old direction has stopped suddenly and it vibrates. The bumps get farther apart as the head speeds up.

The best fix for this is usually to change filaments, change temperature or if you are patient, lower the acceleration to 1000 mm/sec/sec and that will go away. But you might then get other quality issues - especially at corners. 3000 mm/sec/sec might be good enough for you.

If you print this part with a matte surface instead of glossy you won't be able to see any of these "ringing" issues or other "buckle" issues. Unfortunately there are not many companies who sell matt finish filaments. Woodfill and stonefill are two that come to mind.

[GeorgB 0]

printer: UM2

in CURA speed 50 mm/s (acceleration cannot be set in CURA, or did I miss that point?)

I have ordered now different ABS-filaments to check if that has an influence...

[gr5 2,265]

Acceleration is in the menu under motion settings I believe. They will not get saved the next time you power cycle unless you specifically save them to eeprom. The menu's are different depending on the firmware version and I don't know what has what. You can also modify acceleration settings with gcodes.

Note that color is more important than brand - crazy as that sounds. For example white PLA from at least 3 different manufactures seems to be more melty at 210C than most and it tends to string more and slightly more difficult to use for most projects. It must have to do with the most commonly used dyes? Matte finishes look - so much better.

[yellowshark 153]

FWIW I printed your model and had none of your problems. PLA at 30 or 40mm/s

[GeorgB 0]

That is the point: I have printed maybe a month ago the same part, same filament, same acceleration, same speed with no problems at all.

That brings me to the point that it is a hardware problem, nothing to do with software.

My suspicion is that the bearing bushes do not glide easy - when I move the nozzle with the bearing bushes without power I can feel different resistances on the way. So maybe there is a slip stick which generates a kind of vibration?!

When you move the nozzle without power, is the resistance always the same? or do have stronger and easier points?

[yellowshark 153]

My personal experience is that it is always the same

[neotko 1,417]

Just wondering, did you refresh the machine with sewing machine oil so the shafts (except z shafts ofc) move like new?