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frederiekpascal

Any tips for avoiding these ugly strings on the wings? :)

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Hellow all,

I tried to print this model : http://www.thingiverse.com/thing:246198 in PLA (210°/60°)

But as you can see on the pics below, the result is not what I expected. Ugly strings on the wings :p

These were my settings :

layer height 0,06

shell thickness 1,2

retraction : yes

retraction settings :

- minimum travel : 1mm

- enable combing : all

- minimal extrusion : 0,01

- Z hop when retracting (mm): 0,0

bottom/top thickness: 0,6

fill density: 15%

print speed: 25 mm/s

support type: none

platform adhesion type: brim (30 lines)

initial layer thickness: 0,3

travel speed 200mm/s

bottom layer speed 15mm/s

all the other speeds are on 0 so they have the travel speed indicated on top = 25 mm/s

is there a way to export these settings without the need of typing them all? :D

Yes, I've read http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide but I couldn't find what I did wrong... :s

Any tips to help me out?

Photos :

Gcp7Jp9.jpg

H3f7Ukq.jpg

ZTJGrij.jpg

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Usually as a rule of thumb I use these ratios for PLA (different brands may vary)

0.1 | 25mm/s | 195ºC

0.1 | 50mm/s | 210ºC

0.1 | 80mm/s | 235ºC

If you see some of this stringing occur during the print, in the tune menu you can tweak the settings (increase or decrease temperature) until it disappears.

Eventually you'll develop a pretty good feel for this right away :)

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Did you change anything in the retraction settings on the printer?

 

Hey Didier,

I made some small changes to the retraction settings.

The default settings are :

Minimum travel : 1.5mm

Enable Combing : all

Minimal extrusion before extracting : 0.02mm

Z hop when extracting : 0mm

These are my settings :

Minimum travel : 1mm

Enable combing : all

Minimal extrusion : 0,01

Z hop when retracting (mm): 0,0

I made these small changes after reading this article : http://www.extrudable.me/2013/12/17/highqualityultimaker2/ (check his pics, he made some really nice prints...)

Any good changes or should I go back to the default settings?

I'll change my travel speed to 250mm/s and I already got rid of the blue tape. ;)

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Usually as a rule of thumb I use these ratios for PLA (different brands may vary)

0.1 | 25mm/s | 195ºC

0.1 | 50mm/s | 210ºC

0.1 | 80mm/s | 235ºC

If you see some of this stringing occur during the print, in the tune menu you can tweak the settings (increase or decrease temperature) until it disappears.

Eventually you'll develop a pretty good feel for this right away :)

 

Ow that I didn't knew... I never changed the temperature for my PLA, I always sticked to the 210°/60° default settings... When I use 0.06 and 25mm/s should I go lower than the 195°C you're indicating?

Should I save my slicing in reprap or Gcode? Cause when I use Gcode then I have to make the temperature changes on the ultimaker itself and not in Cura?

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For the um2 family you normally use the defailt ultigcode and set temp on the printer... but some people don't like that...

I don't think youll ever go below 195. I find that already rather low. For good quality I usually use 205 c at 35mm/s but you just need to try and play around.

 

and good quality is 0.1mm for you or do you go any lower with those settings? (205°/35mm) And do you also have your travel speed that high? 250mm/s?

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In general yes I consider 0.1 good , but it really depends on what your making, I don't make tiny scuptures and stuff, mostly mechanical / functional stuff, often 0.15 or 0.2 is ok too. If your model must have a nice looking slope it makes more sense to go lower (on a slope you'll see the layers more as stairs), if it only has straight walls it makes less sense...

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As others said, if you slow it down (35-40 mm/sec) you will see good results

Depending on your filament requirements, as well.

I find 208-210 to be the sweet spot for my Ultimaker Original using ColorFabb PLA/PHA

I do start the print at 220 to get a good flow going, then tick it down after the first few layers are down.

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Is this after clean up?

It looks much better already.

And like stated before, you do need to play around with it a little bit.

It also depends a bit on a potential draft, ambient temperature, colour of filament.

So really interpreted it as a rule of thumb, and not absolute knowledge.

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You could print 2 towers 50mm apart or so for testing purposes.

You can check things like making sure the bowden tube doest move while its retracting at either end.

You can adjust temps while its printing the towers every 10mm or so to see at what point it improves.

you can do the same test and increase the retraction distance .5mm every 10mm

As sander points out, there are multable factors that can have an effect and what might be perfect for me maybe 5 of 10 deg out or .5mm retract distance for someone else.

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I don't feel any smarter but ever since I got the new 2go everything just seems to print so well, doesn't matter what I throw at it. ( apart from that crappy silver roll I got )

Now my other UM2 feels neglected. :) ,It definitely needs a few trials done on that as I have had it apart so many times the setup is allover the place. :(

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From the start should be fine. if you lower it during the print it will drop passed your set point 5 or so deg until it comes back and stabilizes. you can risk under-extrusion if done that way.

 

That I didn't know, thanks a lot for the great tip! Cause I was playing around with the temps like this :

layer 1 : 210°

from layer 10 : 205°

from layer 20 : 200°

from layer 30 : 195°

and I was seeing ugly results on the bottom layers.... printing Colorfabb PLA again now on 30mm/s with 195° from the start :)

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