Terrible Print Quality Issue

[DeanUKengr 0]

I am trying to print 1 foot rectangular bars vertically. While I know that a tall, slender part printed vertically is not best, I know it can do it reasonably well because I've seen it done with this same part before on this same printer.

As you can see from the image, the printer isn't printing the parts well at all. It used to print well but it seems to not want to print right all of a sudden. I have tried the Atomic Method to clean out the nozzle but that didn't seem to work. Even if I print this lying down (which would make it much smaller and I would like to try and avoid that) I doubt it would improve quality since it starts printing like that even at the base plate.

Any help would be appreciated.

[gr5 2,271]

This is typical underextrusion. Pretty severe - Somewhere around 30% to 50% of the extrusion desigred (half to a 1/3).

There are many possible causes. The likely problem is either your teflon part or your nozzle. But first the most common problem is that people print too cold or too fast. Check the table below to see if you are printing too cold or too fast (fast has to do with layer height also!).

If you have the Olsson block this might be a good time to install it. Read the directions carefully - it's very very easy to destroy the temp sensor - but the guy who wrote these directions changed 100 blocks and only damaged one temp sensor so read his technique. Change the teflon part while you are at it. Often there is a thin coating of gunk inside the nozzle - especially if you printed with ABS a few prints ago. You can either put on the olsson block or you can remove do a cold pull, then remove the nozzle and soak it in acetone overnight (again be very very careful not to damage the temp sensor). Here's the directions:

http://support.3dverkstan.se/article/62-installing-the-olsson-block-kit

There are about 15 other possibilities so tell us more information (e.g. I changed the nozzle - that's not it, I change the teflon part 2 days ago - that's not it, I am printing same speed (but thicker layers) that used to work).

Here are my recommended top speeds for .2mm layers (twice as fast for .1mm layers):

20mm/sec at 200C

30mm/sec at 210C

40mm/sec at 225C

50mm/sec at 240C

The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA.