Subscribe to MyTechFun on YouTube. Dr. Gaspar always has the latest materials in the queue for testing.
Right now PPA-CF seems to be the sweet spot for price vs. performance vs. printability.
this post was submitted on 04 Oct 2025
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Traditional PA6-CF is still arguably a better choice as it has higher impact resistance and it's cheaper. Dr Gaspar has great videos and is the best resource available on youtube, but you have to take some of his results with a grain of salt as he used to have constant troubles with layer adhesion in older videos when he was printing with open printers. And he doesn't run all tests across the temperature range which sometimes might change the properties, uses very small sample sizes and sometimes doesn't follow up on weird outliers.
Just wait until sirayatech drops ppa-gf later this month for 45$
This will be a hot take but I think the community is too conservative with materials. I understand that printed bang sticks are inherently dangerous and it's best to be on the safe side, but there was a guy on reddit who printed launchers out of ASA only and got shit for that despite having working proofs. There even was a guy who posted a beautiful Urutau made from Creality Hyper PLA-CF and claimed over 100 rounds without signs of damage. OG FGC-9 readme calls for plain PLA. That is not something that an average Joe should do, but experiments could lead us to material independent designs. And it would be a good thing, Homeland security can't put everyone who orders any type of filament from Amazon on their watch list.
I went through 2kg of 72D TPU testing it in several different designs. You can find my report on Odysee, but the tldr; is it didn't work - even with design changes. I'm now exploring the capabilities of PCTG (with much better results).
But the bottom line is that some materials have limitations that you just can't design around. PETG, PC, and artistic PLA are always going to be poor choices for most functional firearms parts.
You could multi-material to cover the outside in them
makes the print sky rocket in time. i had a print i was setting up in PLA that i didnt want to have to work too much on removing supports so i was doing PLA and PETG and the print time went from 3 hours to 14 hours. need an IDEX
Yeah that is a downside
Hey Ill give your paper a read, thanks for your work. Icant stress enough how important is the work of the devs to the community. I think I once saw an even harder TPU, but that is probably another dead end. I agree that the artistic filaments are a dead end as well, but not everything is what it seems, ie I can't find much concrete data on that CF PLA from Creality but according to some it has better layer adhesion than some non CF PLAs. And dr Gaspar tested the Tinmorry CF PETG that also had better later adhesion than vanilla.
There can be a lot of performance variation across brands which makes generalization really difficult. But when it comes to PLA-CF, the primary thing it's gaining (stiffness) is the one thing that PLA doesn't really need. If you're going to try to anneal it, the CF can really help with dimensional stability. Otherwise, you can almost always find a higher performing non-reinforced version.
As for PETG-CF, it still suffers from extremely low impact strength. That's just an inherent property of PETG and adding CF usually makes it worse. That doesn't mean it's not usable. In fact, there's a video of Middleton shooting a 500 Beowulf upper on a GAP lower printed in PETG-CF. But that's a case of really knowing your performance requirements (the GAP has a bolt-on metal buffer tower) and how to dial in your print settings to get the most out of the material. Most people aren't at that level, and that's the main reason why you see experienced folks playing it safe with recommendations.
Well untill the sub got nuked I had about 5 post of ASA frames failing none of them at the layer lines all being through out the layers so it wasn’t bad printing. How ever you are right the commmunity does have a knee jerk on a lot of materials that are fine for certain things how ever a lot of people who have to ask “is this filament good” probably shouldn’t be printing anyway
I love looking into the hawt new shit, and I'm sure I'll be buying it, but don't get too caught up on new shit. Basic PLA can fuck, I've got an AR lower over a year old with thousands of rounds through it. Don't worry about your material until it fails. Nylon is great too, but whatever works, works. The end goal is just to send boolits downrange.
For the most part, if you dont need your hand held, I would steer clear from polymakers PA/PET offerings. They are geared towards printability (think open-air printers) instead of performance.
Sirayatech on the other hand, has amazing performance for very low price. I have tested a fair bit of PPA-CF (at 62$/kg and 45$/kg if you print with .5mm or larger nozzle, they have a special batch) and have been very happy. However, latest this month they are releasing PPA-gf at 45$/kg and I will have some in for testing soon.
polymaker pet-cf is fine. the differences between polymaker and bambu petcf are diminished returns
If you think it's diminishing returns to go from PM pet-cf to bambu lab pet-cf, why would you choose it over Sirayatech, which is more performant than PMs offering AND much cheaper? You can get PET-CF from ST for 37-34$/kg vs 25$/.5KG (50$/kg).
https://www.youtube.com/watch?v=6qOrv_r-rKU
PM comes in last in every test except for Impact Resistance (which is a fail) and price (because they used the 3kg price.
The PM offering was designed with printability over performance and comes in last place in creep, 3-point bending resistance, tensile, layer adhesion (enclosed)
Where is ST Pet-cf is the cheapest tested and basically always comes in either 2nd or tied for 2nd.
I've been wanting to experiment more with different materials for non-impact parts like grips and what not. Otherwise I kinda just go with what others have put through substantially more testing than I have
I’ve begun to do very similar things. I’ve started to use a combination of different materials for sifferent components to maximize the functionality or aesthetic appeal of each part. Most often I’ve used either PLA+ or nylon for frames and large pieces and PETG-CF for small internals like mag releases. I think from what people have mentioned here I want to try out some PPA-CF next though
Ive been using ppa-cf and its been awesome
Not crazy expensive either
Any experience with PET-CF?
I had some comments on one of my posts saying that Siraya Tech PET-CF and PET-GF have been good for them. I picked some up and plan to give it a go.
Nice
Petcf is a good filament… it prints beautiful and is very rigid
However it gets outclassed by other filaments in certain properties.
If you can print petcf, then you can print pa-cf and pa-gf which have much better layer adhesion
Both pla and pa have better impact resistance
So for a frame or other load bearing part, others do better. If creep is a big concern, then it may be a good option
Mags are a good use of petcf for example
I think for less load bearing parts it is better and the price is decent as well
I print in Polymaker pet cf. I'm gonna stop though. Just not a good filament vs pla+. I am looking into gkass fibers next
Been printing in PPA-CF and I love it. Extra heat resistance is nice especially for handguards or suppressors since tax stamp is going away soon;)
Do you use similar settings for it as PA6-CF or do you have to develop different ones?
I used 300blk fde settings and crealitys recommended temps for the particular filament I have. The only difference is I slowed the print speed down to 25mms instead of his usual 30mms. I'm still tweaking the support settings because they're a real bitch to get off. I'll probably make a post once I find something that works!