Ultimaker 2: Nozzle dragging through prints and squahing models.

[MGFRD 0]

We have had various successful prints using our printer, but now we are having issues with the nozzle dragging through printed material and squashing prints. Weve adjusted the build plate height and levelled it several times, but we are still encountering problems.

Any suggestions would be massively appreciated?

[gr5 963]

A photo or video would be helpful. There are 3 possible issues you are describing each totally different.

First realize that leveling only affects the first layer. by the time you get to the 3rd layer all leveling has been self repaired by the fact that each layer sits on the previous and eventually they get to the right position. This is easier to show in pictures than words.

Is your problem top and bottom layers only? If so try turning off the "combing" feature - that will make a huge difference. And make sure retractions are enabled. Please post picture.

[MGFRD 0]

Please see the attached photo.

This model was the 1st of an array of bad prints and seemed that the nozzle was dragging through previous layers which caused the model to spread out.

Now it seems that that no were near enough material is being extruded through the nozzle for it to print at all, potentially a feeder issue?

[Labern 718]

I guessing this is quite small. Nothing to compare the size to.

But what you are experiencing is the print is getting to hot.

When you have a large print, as the nozzle moves around the fans blow on the whole print and it take quite a while to the hot nozzle to reach an area where is has previously been. This allows the plastic to cool and go hard enough to not be effected by more hot plastic being up on top.

Small objects don't get this chance to cool and end up getting hotter and hotter till you have a blobby mess.

To fix this try printing 2 at once. this means as one is printing the other is cooling and if you have them side by side the fans with blow on one while printing the other.

[Labern 718]

You may need to do an atomic pull to clean the nozzle. but there is a lot of information about extrusion issues in the support section.

[gr5 963]

What labern said. I assume this is the width of a pencil. Print 2 at once and make sure you have "all at once" mode and not "one at a time mode" chosen in the menu.

[peggyb 139]

do you mean something like this?:

it starts around 0.30 and when it gets to 1.00 the over extrusion is really visible when the nozzle is dragging through the pla.

I have no idea what is is, the funny thing is that when I restart the file it could be good or bad again.

(printed with a brand-new Ultimaker2Go, right out of the box)

 

[gr5 963]

Damn it I should NEVER answer any question without a photo or video first.

The problem is the part is not cooling enough - the head is keeping the part warm.

The only reasonable solution is to print two "pencils" side by side so one has 3 seconds to cool while it prints the other.  This will make a HUGE difference.

Edited November 19, 2015 by Guest

[neotko 1,362]

Also you could turn the fans at 50-70% propably since layer 1 since you use bluetape because no heated bed. Don't go 100% at the start to avoid cooling too much too fast the hotend.