I need to print a couple small parts that can take a few hits and survive. I’m thinking of using poly carbonate but I don’t need anywhere near a full roll. Would anyone be willing to sell me a bit of a roll they have?
Alternatively does the 3D space team have use for PC? I can buy a roll and donate the remnants (a nearly full roll.)
We don’t have any around at the space, however we do have Zephyrus set up to handle engineering filaments. It can handle the mid range of PC printing temperatures - 100C bed and 300C nozzle, with chamber heating to 70C. Remember to use the dryer there as well!
A couple recent deals on PC-ABS blend recently, though they may be expired:
So far, I have only tried PPA-CF, and it was the most difficult temperature tower to break that I’ve ever printed. But it printed well and the build plate was very cooperative. If you have leftovers of PC, I will definitely test and tune in some settings on Zephyrus for Asmbly shop prints! Maybe we can consider a ‘take a gram, leave a gram’ area for small engineering filament quantities. 
In case you don’t need perfect rigidity with your impact resistance - consider a high durometer TPU as well - like a 98A. Nearly isometric layer adhesion, but enough flex that impact energy is absorbed quite well.
i have used polycarbonate extensively. it is strong, rigid, excellent layer adhesion. moderately difficult bed adhesion. likes high temp enclosure. hard to keep dry and needs a high temp dryer to dry back out. can string out in insanely fine threads (like running through a spider web), usually due to moisture, but a high temp heat gun will smooth that out instantly. makes fine detail. does well with bridges
the clear version is considerably stiffer and stronger than the colors.
it is slick. makes very good threads. it can be smoothed and even made watertight bu painiting with UV cure epoxy and hitting with uv. the uv epoxy trick basically works on most filaments, but it works better with transparent ones so no place is obscured
it does have some extra concerns with bisphenol-A and some other fumes.
ppa-cf is in a different class. it’s wildly stiffer and stronger. needs a hot enclosure. does not string. must be kept dry and if it gets damp a regular filament dryer WILL NOT work, this needs a higher temp to dry. it must be printed on a garrolite bed with binder clips, NOT PEI (will weld and destroy the plate), and has hard limits on how the bowden tube can routed because it’s about as flexible as uncooked spaghetti. has not been great with bridges though.
but, once you understand ppa-cf, it’s actually one of the easiest to print with. almost always adheres without a brim and always releases easily. it’s a bit pricey per kg but you may be able to reach strength and stiffness goals with less filament overall