Back in May I needed some rigid filament for a project I was doing. I had recently watched Zach Freedman’s youtube video: filament tier list. In it he puts Priline Super Hard PC-CF filament in A tier for it’s extreme rigidity. So I bought some and it printed nicely so I was happy at the time. I had about 800 grams left over which I printed my LR4 core from along with a few braces. Last week when I was ordering filament for my LR4 build I went to check the datasheet to confirm the young’s modulus but could not find it. So because I’m an engineer with a number shaped hole in my heart I couldn’t let it go. I made a 3 point bending jig and to estimate the youngs modulus. In addition to the PC-CF I tested samples of PLA, and PETG-CF that I had on hand in order to confirm my measurements were relatively accurate. The results were shocking. The PLA measured at about 3,300MPa and the PETG-CF at 2,700MPa. Which are both very close to what I expected for those filament types. But the PC-CF measured at a very disappointing 2,000MPa!!! For a filament who’s one job is to be rigid this stuff is very disappointing. And for reference dried it for 12 hours at 70C and printed it directly from the dryer connected by ptfe tubing to my enclosed Bambulab P1S.
Anyway I’m waiting for some Polymaker PET-CF to print the rest of my parts along with some samples of CF and GF nylon to test. I’ll likely end up ordering more to reprint the core and braces I printed with the PC-CF.
Neat. Appreciate the info, and look forward to seeing what else you observe. Am especially curious since I have some PC I need to learn how to print well.
I printed some PETG with my new printer and it was stiffer than I expected but super brittle and snapped like glass. After a bit of googling I found out that this can be caused by excessive part cooling so I turned off the part cooling fan and the next part was much less stiff and didn’t break under deflection. I wonder if it could be something like that.
That is pretty strange. I really really hope some sort of mistake was made. I have never printed PC but I know the PET is very obviously rigid, can’t wait to see your numbers on those.
I think I’ve found a lead on this. If I look at the recent 1 star reviews on Amazon for this filament I’ve seen a pattern. There are several people who say they have used this specific filament for years but that it suddenly became terrible. One of those was from early June and I bought the filament in May. So I think this is what happened. I doubt this is an indictment of PC-CF across the board but specifically “Priline Super Hard PC-CF” and probably a lesson to me to stick to more reputable brands.
Early on when I was printing things (Using Lulzbot AO10x series machine, around 2013), I had several spools of “ABS” that absolutely were not. (Would not dissolve at all in acetone).
Carefully examining them, the outside and inside were different materials. I have no idea what those were, but that was the first of many times I’ve had crap from a supplier.
The most recent ones were from Inland filament “sales” at MicroCenter- which I suspect were actually product dumps of batches realized to be crap, but not declared as such.
I’ve tried printing pc for a gear for a 3dsets RC car. The printer was in a warm enclosure, and the pc in a filament heater/dryer. The gear part turned out very brittle and broke too easily. I don’t know what I did wrong… I just settled on pc being too exotic for my taste…
