Sorry that it did not answer for a while, I had a busy time.
Right now i started again with the (damn) printer.
As before I'm having some serious problems.
When I start printing the first layer of the raft (thick layer) looks awesome. Than the second layer of the raft (very thin one) has already some serious problems with underextruding. Wheel is spinning but it's not pushing the material. Than the first layers of the print itself are barely even there before for some reason the material is pushing again, After a while it's not pushing, than its pushing again and so on. (Picture 1)
At some point (sometimes) it will stop at all and the printout will look like this: Picture 2
If i remove now the filament, the head will look like this: Picture 3
The crazy thing is, if it gets plugged and I don't do anything besides removing the scrap part and start a new printout, it will work again: no plug, nothing, until it comes to the second layer of the raft....
So what could be the problem?
50 mm/s (everything faster doesn't work at all)
240°C
all other settings standard
I also tried different temperatures, printing speeds and so on, but nothing works consistently :-(
Any ideas? Thank you!
1 http://imageshack.us/photo/my-images/694/32t3.jpg/
2 http://imageshack.us/photo/my-images/694/hqk5.jpg/
3 http://imageshack.us/photo/my-images/827/pc5n.jpg/