Filament cooling problems
I've been having an issues where parts of new layers will curl up after being laid down. This mostly occurs when building out at an angle and on the back of the prints.
I'm starting to suspect that this may be a problem with the cooling fan duct. It appears that when the filament is being laid towards the front of the machine (i.e. Into the airflow) I have very few problems but when the filament is being laid towards the back of the airflow (i.e. Away from the airflow) I get the curling problems.
I have been thinking of redesigning the fan duct but was wondering if:
1) anyone else has had this problem?
2) anyone knows of a good design?
3) would PET be appropriate for a piece that's right next to the hot end?
Below are a few pictures. Two of a pangolin that was printed diagonally on the bed showing opposite sides of the same tail segments and one of adalinda in progress with significant filament curling.
I have have this same problem trying to print the tree frog, I have never had a successful one because the front legs get layer uplift in the back and pull off the print bed.
Re: Filament cooling problems
There is a nice reworked fan outlet here: http://www.thingiverse.com/thing:1947953/#files
I printed in PLA and it works fine.
You are indeed correct in that curling occurs when the plastic is not sufficiently cooled. You can prevent the problem by slowing down the overhang perimeters or the outer perimeter in general which will also give a better finish.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Filament cooling problems
Thank you Peter,
I had seen that design on thingiverse before so I will give it a try. But I may also work on designing a fan duct that directs airflow around 3 sides of the nozzle to create a more efficient cooling system.