ABS continuous jamming

K8200 3D Printer K8200 - Issues while printing
1

I’ve been printing small products for a while without problems. After changing new filament (ABS from Velleman) the first couple of prints where without problems, but after 4 products the ABS jammed in the hot-end or teflon tube. I dismounted the hot-end and cleaned everything, but after 1 or 2 minutes it jammed again. So I cleaned everything again en after 1 or 2 minutes the ABS was stuck again.

I really do not know what I must do next. I checked and cleaned the extruder and it is working fine. Cleaned the hot-end more then once. The only thing that is crossing my mind is that the ABS thickens in the teflon tube because of the heat, but is not melting yet. This might cause enough friction so the extruder can’t give enough force to push the ABS through the teflon tube.
I tried a new roll of ABS, but the problem is not going away.

Does anyone has a suggestion of what to do next?

2

You are printing with right temperature i assume?

3

Yes, I am printing with the settings downloaded from the site. That would be 240-245 degrees.

4

Have you changed the retraction length? To much on ABS can jam the nylon tube in my own experience. I use the Cura default of 4.5 mm retraction now and it works great, can be some small threads if there is a fast travel right after but in normal print speed there are no threads.