Extrusion issues

[young_gun 0]

Hi,

My company has had its Ultimaker 2 Extended for about 3 months and up until now it has been performing well. About 3 weeks ago, I set it to print overnight and when I came to check on it in the morning, the spool had got tangled in itself and the feeder had ground away the filament. The printer obviously continued what it needed to do and I came in to see a mess. Ever since then it has not been extruding properly. I have cleaned out the hotend quite a few times and replaced the PTFE coupler, which to my eyes was fine but decided to replace it anyway.

Where I seem to be struggling is anything that is circular, it just flat out under extrudes even if I pump up the heat to 230 and push the flow rate to 110%. And I am not pushing the speed either, the last print I was running at 40mms max, slower on the inner perimeters. Oh and the filament is colourfab.

Its just not been itself after that day. Should I look at maybe replacing the hotend? I have a Printrbot Simple Metal as well and this kind of stuff is either a result of the hotend being dirty, dodgy filament or just running the printer too fast. Nothing which can be the problem here unless the hotend is stuffed.

[DidierKlein 729]

Hi,

When you say you cleaned the nozzle, do you mean that you used the atomic method?

How do the atomic pulls come out?

Here's some more information about underextrusion it can come for many reasons.

[young_gun 0]

Hi,

I originally did the Atomic method and got a tiny needle and cleaned out the nozzle. The last time I cleaned it out I got the perfect cone :/ I'm really at a bit of a loss since it seems like the printer is coping with straight lines, it just gets thrown with circles. I think I am just going to remove the entire hotend and replace it and see what the out come is. I'll go through the info again, thanks for the link

Edited February 18, 2016 by Guest

[young_gun 0]

Well the hotend is clean.

[SandervG 1,521]

I haven't come up with an explanation on the fact it only under extrudes circles, but have you also cleaned the feeder? If it dug its way through your filament it could mean the knurled bolt still has some dirt on it.

Is your bowden tube all the way in, and there is no play in it? (By hand you can not lift it up from the head, even a few mm?) Maybe retraction is suffering and priming isn't coming through well. Maybe it could be interesting to do a print with circles and without retraction, just in an attempt to isolate the problem.

Good luck!

[young_gun 0]

Well I tried printing another part and it seems like the under extrusion stopped happening so it may have just been the print but there is still under extrusion happening on the corners of the new print. And yes, I have cleaned out the feeder and the tube is all the way in. I'm starting to realise now that the bowden tube does have its complications