colorfabb xt fillament issue :layers and threads not bonding

[themba]

I just tried printing with xt fillament for the first time. Of course it failed miserably

threads and layers are not bonding properly. The attached image was made after a few layers on our ultimaker original with heated bed. The threads are not bonding properly. I used the default printer settings with 2 ajustments: nozzle: 250’C print speed: 50mm/s

My best guess is that the nozzle temp should be higher. Can anyone confirm that that might be the cause? Any other suggestions?

[James_2]

worth trying a few things

how hot is your bed and what are you using to hold it down - XT does not particularly like glass - I can only get it to work on blue tape (unheated bed)

do you have a fan on? (I have found XT does not like to be cooled too fast in the first few layers)

XT shrinks - and so works best (for me) at lower layer heights, slooow and without a fan.

James

[themba]

Interestingly enough the adhesion to the bed is fine (see image). It’s the layers on top of that which come loose from the earlier layers. The bed is 70’C (default)

I set to layer height to relatively high(0.25 if I remember correctly, I’ll look it up) because I read somewhere that that works best for xt. What layer high do you recommend? less than the default 0.1mm? less than 0.05?

Given this type of error (see image) which parameter is most likely at fault? nozzle temp? bed temp? layer height?

Thanks for the other hints. They are very likely to be usefull in the near future:)

[MB3D]

I’ve printed multiple kilograms of XT with great success, when using gluestick on glass at 70C you will have an easy adhesion method. Printing at 250-260c gave best results. When you’re using such high layers, you should go with a hotter nozzle, as XT needs some time to heat up properly. 0,25mm is only usefull if you want translucent prints, for normal ones you should go with 0,1-0,15mm at 50mm/s. Use no cooling in the beginning and only a little during the printing (30-50%. Good luck, Marius Breuer

[James_2]

So - go higher temp, no fan for the first 10 layers and then 50% and lower layer height (0.15) as the first things to try. (The photo looked like the item had curled off the bed so I am just seing that wrong.)

James

[atumedida]

Good day.

I don’t think temp is the issue. I have an ultimaker 2, and I print mostly on pla and colorfabb’s XT, and your settings should work correctly.

As a reference, here are my settings for XT:

For transparent XT I use 215º, no fan, and bed temp 70º.

For Colored XT, I print it at 215º, bet temp 70º. Without fans, also.

When printing with transparent XT it’s a good idea to have a higher layer height, as it makes the print clearer (as in more transparent). For colored XT, I’ve printed anywhere between 0,006 and 0,2mm without problems - not 0,25, I might add.

Try printing the same piece with 0,2mm layer height and no fans, that should make the layers bond properly.

[Batuhan]

I used similar settings as you did, it works fine. Sometimes filament batches can be bad. (happens on esun often, havent seen in colorfabb yet, but it is a possibility) Try with the recomemded settings above, if it doesn’t work out, use another xt spool

[hreedijk]

I agree with the settings of Marius Breuer.

XT is the main filament I print with (90%) and I print a lot, I even build my own printer with it.

Does the filament come out of the nozzle nicely just before the print?

My recommendation is not to go higher then 0.21mm layer height, first layer speed 30/40 mm/s, no fan up to the 3th layer.

3DLac also works very well on the HB, the same for kapton tape or gluestick on the glass plate, but looking at your photo that’s not the issue.

[timberman]

I use often XT, and works great! Lower your layer height than it must go right.

Succes.

[themba]

That’s an interesting question. I noticed that the fillament tends to ‘curl up’ onto the nozzle just before starting to print. I didn’t notice any irregularities in the stream and the print seems to start okay. The first layer actually looked pretty neet after printing… Thanks for all the tips. I’ll try again soon.

[James_2]

curling up can be fine, and can also indicate a blockage (less flow) but from the noodle your flow looks ok. Wipe the nozzle when it is hot with a lint free cloth and then the noodle should straighten (sometimes takes a few goes) if the noodle never straightens then their could be a slight blockage and you should to the “atomic” cleaning method. (see UM forums for explanation)

But try a simple wipe and the other stuff first. - your layer height, and speed and temp are just at the absolute top end for how much the UM can heat and squeeze through the nozzle (Again look at UM forums for a calculation on volumes)

[MB3D]

The curling can also happen, when the cooling fan is powered while you’re extruding plastic. Make sure, to have the fan at 0% or hold something in front of it, when you check the extrusion behavior. Also don’t forget to check the filament diameter and tighten the drive gear a little bit. XT is very though and I had no problem with overtightening, ever. The material is somewhat smooth and too less pressure on the drive gear may cause skipping

[designeering]

I’ve had good results with XT on an Ultimaker 2 with the following settings:

1. select UPET preset for the material

2. then use the fine tune menu:

- set build plate to 70 ˚C

- set speed to 70% (for the first layer only)

3. apply glue stick on the glass bed

[KCT]

250 seems a bit to hot…i would sugest 200…225 max

print speed is ok, you could try to increase the extrusion rate by 5 to 10%

heatd platform at 60 degree

[ColorFabb]

For the XT material 230C is really the lowest you could go without sacrificing too much layer adhesion.

[ColorFabb]

Hi @themba, I see a lot of comments already, how’s the 3D printing with XT coming along? The default print settings for the UM2 are probably 0.1mm layerheight, I would start with 0.2mm layerheight.

[LudoFR06]

Totally Agree.

Try to be within 235-240 Deg C range for maximum strenght and layer adhesion.

BR

[themba]

Thank you all very much for the helpful comments!!

I was feeling very brave yesterday and immediately printed the desired object without further tests. Usually these decisions turn against you but yesterday I was lucky for once…

Attached is the new knob to control my oven I accidentally destroyed the original while cleaning and PLA (my usual printing material) was getting wobbly by the heat escaping from the oven…

These were the settings that worked for me might anyone have the same issue:

um original+ with default setings except:

+ nozzle: 255

+ layer height 0.2

+ fan: 0

+ bed: 60

+ print speed: 40