Extruder overflow

[nab 0]

Hi all,

I have a problem with my Ultimaker, but I think it's best displayed in photos.

here's the extruder head before starting to print

https://dl.dropbox.com/u/9922538/Ultimaker/Beginning.JPG

here it is while it's printing

https://dl.dropbox.com/u/9922538/Ultimaker/During%20Print.JPG

and here it is after it finished

https://dl.dropbox.com/u/9922538/Ultimaker/End%201.JPG

https://dl.dropbox.com/u/9922538/Ultimaker/End%202.JPG

as you can see, we start with (almost) clean extruder head with the heater, but while it's printing, the plastic is oozing from on top of the extruder head (from all around it).

and it seems as if there's too much and it's oozing too slow, so, it's overflowing from the top side of the heater.

note 1: this was a 30 minute job, the problem gets worse with time and eventually it drips some burnt plastic drops (brown instead of white) on the printed object

note 2: I some times (including in this print) take a small piece of paper and try to wipe the overflown plastic onto it and away from the head so it wouldn't drip.

my question is how do I prevent this ?

is it from extruder steps calibration ? or is it a hardware issue ?

using Cura 12.10_RC4 to build the gcode and Pronterface to print it

[Daid 306]

The hotend is leaking, could be a gap between the nozzle and the brass part. Make sure the nozzle is screwed in tightly. As well as the brass being screwed in tightly. Your hotend needs to be hot to do this, as it will break otherwise.

If this doesn't work you could put in some teflon plummer tape on the treads to seal it. Shouldn't be needed with your V2 hotend, but it sealed up V1 hotends quite good.

[nab 0]

hi Daid,

thanks for the reply,

especially thanks for the warning about doing it while the hotend was hot, I would have broken it otherwise.

you were right, I tightened it from both sides (nozzle & brass), and it's working fine now.

of course, I had to re-align the z-axis after I tightened the nozzle. (just mentioning it for anybody who would have the same problem)