waves only in black ABS -- Solved --

So I noticed that anything I print in black that has any large flat areas and is printed solid has these waves. The waves start on the first layer and transfer to all other layers. If there is say 50% or less infill then it goes away and the surface if perfect. At first I thought it was my ABS slurry on the PET tape being uneven from other prints so I even changed the film and printed fresh with same results.

The photo attached was taken while printing first layer (a bit blurry due to movement) but you can clearly see the start of the wave like surface. If I print with any other color I don't seem to have this issue. The black is from Ultimachine and other than this wavy issue it's a perfect filament.

Just wondering if anybody knows why?
Or has had the same issue? or what?

If I print items with less that 100% infill it's fine but I print a lot of thin (2-3mm) flat items.

Just curious.

Edited 1 time(s). Last edit at 08/11/2013 04:56AM by tmorris9.

A little more info. I used my 50x USB microscope to check on the backside (touching glass). Attached the images of the back where the top is clean and flat and where it shows the waves.

Did you calibrate the extrusion temperature for this particular filament?

I was not aware that it might take a different temperature. I print all my ABS at 240c but I think my thermistor reads a bit high so it's likely 230c - 235c in reality.

Black ABS tends to need a higher temperature. You can try bumping the temperature up ~10 degrees to start but if your extruder has PTFE liner that might be the maximum temperature before the PTFE starts to melt.

poor adhesion from feedstock slipping (uneven layer of abs). have first layer at half current speed. what happens when first layer filament extrudes unevenly, there is pulling of surrounding layers.


there also is a lot more back pressure on first layer, this makes feedstock harder to push thru.

others may have different advice.

OK tried a bunch of things, higher temp, lower temp, lower nozzle (to press the filament into the glass more) higher nozzle, nothing helps. So I started playing with extrusion multiplier and found that setting it to .7 the first layer prints flawlessly but the other layers are not getting enough plastic as there are slight empty lines between each line of print. hope I am conveying this right. layers 2+ are not getting smashed (<- technical term) together. at a setting that helps the first layer.

I have printed all the way down to .4 extrusion multiplier and the first layer is OK but at that low the rest of the layers look more like sand paper as it's not getting enough plastic and just making dotted lines.

So it would seem that the first layer is getting too much ABS only with black.

I wonder if changing the nozzle size (in slic3r settings) would be the same basic thing as extrusion multiplier? I.E. I think if I told it I have a .4mm nozzle instead of the actual .35mm nozzle then the software may lay down less plastic?

I think if there were a 1st layer setting for multiplier I could fix this easy.

An update with more photos with the extrusion multiplier set to .7. You can see the bottom looks ver good but on the top there is space between the lines. you can even see down a few layers.

reducing extrusion multiplier slows down extruder. possibly within range for it not to slip as bad.

Wow, OK so I started looking at other settings in Slic3r and found a option I am sure I never even went into "Printer settings / Advanced" and found "first layer width" set to 200%. Changed it to 0 (default) and set everything else back to my normal parameters and it printed perfect. I am sure I never changed that as I don't even think I ever went into "Advanced" before.

Not sure why this did not affect other colors, or maybe it's just more visible in black. Anyway I am happy to say a long standing problem is fixed.

Thanks for the ideas.

Just a thought, but did you try this setting also with other colours?

Maybe setting it from 200% to 0 will work for black, but im not sure if it has the same effect in other colours.

In my Slic3r, 200% was the default setting. Maybe there is still something else wrong and this is only a fix for the effect and not the cause?

I get this problem with silver PLA which looks similar to TMorris's problem. I think James is on the right track 'cos I can see the current track being printed pulling on the adjacent track. Dunno why it happens though?

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Waitaki 3D Printer

I think it's an issue with black. Just looked at some other colored prints I did with the old setting (silver and natural) and close up they look perfect.

I had a black from another distributor (3D Ink) that I could not get to print at all, it just sporadically extruded and the final surface looked like someone hit it hard with a wire wheel, chunks all over, gaps, little pills...

So it could be that black is just touchy by nature and I am fine with this one using -0- in that field. The 2 test prints I did with that setting and black came out flawless, good looking, great layer adhesion, great strength, flexible in thin layers.

So unless some other cause or solution is found, I will just remember to print black at 0 (default) first layer width.

I had a look at my "Advanced". "First layer width" in slic3r and it was set to 100% - I also changed it to 0 and the silver PLA printed good. Bloody mystery

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Waitaki 3D Printer