Hi everyone,

We are having some tests with our new Ultimaker 3.

Unfortunately we realized some problems concerning the print quality (see picture enclosed).

We used PLA to print several objects like keychains, buildings, boxes.

The problem is, that we see some bubble-like overflows. These overflows occur only at some points of the object (for example the upper part of the keychain), other layers are really good concerning the print quality. Do you have an idea in which way we have to change our print settings in order to get a better print quality?

So far we used the following settings in Cura:

Layer height: 0,06mm

Infill density: 50%

Printing temperature: 195°C

Build plate temperature: 65°C

Print speed: 30mm/s

Diameter: 2,85mm

Flow: 100%

Thank you very much in advance for your comments!

Hi,

does it happen with the built-in default profiles in Cura 2.5 too?

can you try using the default settings?

infill should be 20 percent by default, print speed should be 60 , build oplate should be 70 and the printing temp should be 200… (starting at 200, then back to 195, cooling down to 180 for final…

what happens with the default settings?

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Where is the pla coming from, and is it a large spool ?

I had the same problems, when using colorfabb large spools …

Maybee you can solve it with “experimental”-“coasting”. It stops the materialflow just before chancing layer.

You can also lower your temperature to 190. It is a small object and you are printing a little slow so your filament becomes quite liquid.

It seems that you filament temperature is too high, although with 195 degrees should not be a problem. Which retraction settings are you using? And which version of Cura?

you could have a look at the minimal layer time, forcing a wipe and prime tower would also work.

basically it looks like the layers you are printing on top of don’t get enough time to cool down, before another layer is printed on top.

though I thought there was something in the default profiles that takes care of this better, maybe it it turned off when you tuned the temperature, etc, yourself?

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Hi

Is that the firmware of the machine has been updated?

I advise a temperature of 200 see 205 ° CIs that the firmware of the machine has been updated

Hi!

The layers don’t have enough thine too cool down. The fan speed should be at the max, And the minimum layer time set to 2sec with option which enables print head to move away from the model until it cools down sufficiently before adding another one (cool head

move or something like that).

Temperature of 180 will be enough and print speed of 50-60mm/sec. Otherwise the hot print head stays on top of the model for

two long and melts the deposited layers

all the best

crash

Thank you very much for all your comments so far!

We have already tried the Cura standard settings and had the same problems. We started with a printing speed of 55mm/s and then lowered it to 30mm/s, but still we had the same problems…

We use Cura Version 2.5.0.

Our filament is original Ultimaker-PLA comping from a large spool.

According to your comments we will now try with a lower print temperature.

Further settings according to your questions:

Minimum layer time is 5s.

Fan speed is 100%.

Retraction speed: 25mm/s

Retraction distance: 6,5mm

Retraction extra prime amount: 0 mm3

Retraction minimum travel: 0,7mm

Are any of these settings problematic in your point of view?

Thank you very much in advance for your help!

I agree that layers aren’t cooling down enough at the top as each layer prints too quickly to give it time to cool. There are many solutions but the best is to print something else next to this part so that print head can go over there and print that. Ideally in a location where the side fans still help cool Marvin. In fact I would print 2 Marvins. I have an STL file that is a cube and sometimes just palce that on the bed and rescale it to be a little taller than the print (Marvin in this case) and maybe 10mm on a side.

As @gr5org suggested, the usual trick with Marvin is to print more than one at a time (or print something else the same height, as suggested, like a 10mm “tower”). Have you tried this?

I haven’t read the other comments yet, so I’m not sure if this is mentioned. Your layer height is very low. A nozzle diameter of 0.2 or 0.15 mm is necessary for this layer height.

Believe it or not the UM2 and UM3 can do .06mm layer heights with a .4mm nozzle. I recommend people go a bit thicker. I’ve never had the patience for a 50 hour print. But you can do it. You can’t really go much thinner with a .4mm nozzle though because… well I’m not sure why. I think the quality starts to get worse again thinner than .06.

I don’t have an UM2 or 3 but with other 0.4mm nozzles when I pushed the layer height too low, I started getting very rough surface texture and seemingly over extrusion. The nozzle could heat up the previous layer since the distance is only 0.06 mm.

Hi everyone,

thank you again for all your comments. The quality of our print definitely improved!

But we still have some problems with the quality of the keychain’s ring as you can see in the picture enclosed.

We printed 4 Marvins at the same time and used the following settings:

Layer height: 0,06mm

Infill density: 50%

Printing temperature: 195°C

Print speed: 30mm/s

Diameter: 2,85mm

Flow: 100%

Do you have any additional ideas?

Thank you very much in advance!

I would experiment with only 2 marvins (to speed up the experiments) and go a little thicker layer and go a little slower print speed: 25mm/sec. Overall it should be faster with the thicker layers even though the head moves slower. Those overhangs are tricky. You can also go even lower in temperature.

Are you using cura 2.X to slice? Your entire remaining issue might be that the infill speed is too fast. When you have a fast infill speed and then switch to the outer layer the pressure is a bit too high and it overextrudes sometimes for a bit.

You can also print just the top half of a marvin to help concentrate on the spots you care about so you can do more experiments in less time (testing .06 versus .08 versus .1 layer height - testing 195 versus 190 versus 185 verus 180C - testing 30mm/sec versus 25mm/sec). Printing smaller prints means you can do more experiments in the same amount of time which means you learn more faster.