PC Blend Carbon Fiber - new printing issues
When I first switched to Prusa PC+CF I was impressed. The end product printed as well as ezPC+CF with little in the way of issues. Now unfortunately I am having major problems with surface texture and fillet overhangs.
The following models were sliced /printed on the same printer one day apart from the same filament spool with the exact same settings (Default Prusa PC+CF Config) 285/115 @2.5 layer height.
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The model on the right has the expected texture and color of a CF part (based on 6 months of printing CF) where as the model on the left has a very rough texture. Assuming there was an issue with the filament I printed the model with a new role with the same results (rough). Thus I do not believe this is a filament issue. During the print the inner layers look great with good adhesion so this appears to be an outer surface issue. My only guess is the outer surface is cooling too quickly even though my fan is off (which might explain the overhang problems on bottom fillets as well). I also measured the temperatures during subsiquient prints and were both bed and nozzle temps found to be within 2-3 degrees of the settings
Ive tried printing hotter/colder (275 / 290) with and without a brim as well as in an enclosure but nothing seems to address the surface texture issue.
Im at a loss at this point and may opt to go back ezPC+CF if I cannot find a solution to this ...
RE: PC Blend Carbon Fiber - new printing issues
@rotor-head
Have you tried a new Nozzle, this could be caused by nozzle wear, or perhaps a partial clog changing the flow of material. As well It might be worth checking the teeth on the extruder, they wear also and get clogged.
Just going from the image you shown it appears to be mild under extrusion.
Good Luck
Swiss_Cheese
The Filament Whisperer
RE: PC Blend Carbon Fiber - new printing issues
Thanks ... I have come to the same conclusions but for different reasons. This particular nozzle has had about 10 roles of PC+CF thru it and I have noted that its becoming more difficult to load new CF filament. Loads PETG just fine.
Ive gone ahead and ordered some replacement steel nozzles as most of my nozzles have seen better days.
I will let you know later this week if that solves my problems.
RE: PC Blend Carbon Fiber - new printing issues
Went to install a new nozzle today and noted that when I took the print head assembly apart I had a bent heat-break. This may explain some of my under extrusion issues. With that said, if my under extrusion issue was due to this I would have thought it would have showed up three months ago when I replaced the heat break & nozzle. Since this was a Genuine E3D V6 Heat Break Im going to assume this was operator error during install. Either way I will go ahead and replace heat break and nozzle and test again.