PLA is probably the most-printed filament on the market these days, and is there any wonder? It’s cheap, it’s easy, and it doesn’t poison you (as quickly as its competitors, anyway). What it doesn’t do very well is take the heat. Polymaker’s new HT-PLA formulation promises to solve that, and [My Tech Fun] put those claims to the test in a recent video.
Polymaker claims its HT-PLA is heat-stable up-to 150 C, but still prints as easily as standard PLA at up to 300 mm/s. By “heat stable” they mean able to maintain dimensions and form at that temperature when not under any load, save perhaps its own weight. If you need high-temp mechanical properties, they also offer a glass-fiber infused HT-PLA-GF that they claim is heat resistant up to 110 C (that is, able to withstand load at that temperature) which is hard to sneeze at, considering you you could print it on a stock Ender so long as you tossed a hardened nozzle on it.
Now it’s not a free lunch: to get the very best results, you do need to anneal the parts, which can introduce shrinkage and warping in HT-PLA, but that’s where HT-PLA-GF shines. If you want to see the results of the tests you can jump to 19:27 in the video, but the short version is that this is mechanically like PLA and can take the heat.
The verdict? If you like printing PLA and want to shove something in a hot car, you might want to try HT-PLA. Otherwise, it’s just like PLA. It prints like PLA, it looks like PLA, and when cold it behaves mechanically like PLA, which we suppose was rather what Polymaker was going for. There is no word yet on whether the additives that make it high-temp increase off-gassing or toxicity but since this stuff prints like PLA and can stand a little airflow, it should be easy to ventilate, which might make for fewer trade-offs when building an enclosure.
What do you think, will you be trying HT-PLA anytime soon? Let us know in the comments.
It’s currently out of stock, so I guess that means a lot of people are trying it out.
assumptions… there could be many other reasons
Don’t be a fud
Operative word: guess
i really liked pla for a lot of reasons but over a span of years every piece became so brittle
i’ve never had call for a high temp PLA but i would love a long lasting one
Annealing, Epoxy or paint coatings, PLA+ or pro.
https://all3dp.com/2/pla-vs-pla-3d-printer-filament-compared/
if one of these “pla+” filaments actually worked over years i’d love it but i haven’t seen any cause for optimism. for years, i used easyfil pla “impact modified pla”, which i think would be described as a “pla+”. it makes a great result that is not very brittle…at first. and then, over time, it becomes brittle even so.
i probably should have given paint a try with my old printer, though. i have the impression it’s moisture in the air that’s turning it brittle, so it’d be hard to seal it up well enough
now that i’ve switched to petg, i’m not very interested in experimenting with pla anymore.
one of the bummer parts is that this weakness of pla isn’t widely acknowledged, i think because of a combination of people not acually caring about the mechanical properties of their products (i.e., minifigs, mando armor) and people not actually using their products beyond the initial “wow it works” phase. having a dozen household objects i use every day seems to make me the exception in the 3d printing world. i think most people just don’t think much of it if 5 years later the part has turned to splinters, so i don’t really trust any reviews on it unless they’re specifically targetted at this problem
PLA can take damage from hydrolysis (from moisture) and UV (from ambient light). Even if it’s not acute, it is cumulative over time, the bonds do t reform.
not entirely sure on that tbh on the spool, once it hits 40% RH, it will be brittle and print like garbage(causes a lot of confusion for new users because they think it’s their settings), it will likely go in a dryer for 8 hours and be absolutely fine for printing again after the moisture level has dropped sufficiently.
It could be that in its unprinted form, that the drying is enough to reconstitute the filament so that it’s good enough and the printing process is enough to remix the component parts well enough to produce decent quality prints. So it may be that it will last longer with drying after it’s printed?
This is all guess work from observations of filaments that gain moisture, get brittle then are dried. I Would love to hear what other people think/know about the processes involved. Constantly drying parts over time is probably impractical though of course.
I’ve been printing Fusion Filament’s HTPLA for years. Not sure if it’s the same resin, but I find it prints a lot nicer than regular PLA and seems to be a bit stronger, too.
Unfortunately these are marketing terms, not agreed-upon standards, so there’s no way to tell short of a lab workup what, if anything, Polymaker’s HT-PLA and Fusion’s HTPLA have in common. A head-to-head comparison would be interesting, though.
That’s factually incorrect. Ingeo’s 3D850 and 870 are named resins that have been in wide circulation with well documented datasheets for well over half a decade and are the basis of the vast majority of HT-PLAs, which is why you’ll find almost all the HT-PLAs sold adhere to the same advertised temperature range and annealing procedures. It’s not like the various “plus” marketing terms thrown around on other materials.
Yeah, I’m a big fan of their work. Pretty transparent with the materials and data sheets, unlike the “PLA+” terminology that gets thrown around so casually.
I can’t view the video from my mobile for some reason, so I don’t know if the video talks about annealing plain PLA? Twice baking this potato, uh, filament seems to imbue it with stronger tolerance properties as well. I don’t think it’s a good measurement of strength and rigidity per monetary unit because you want a thing to hold up or not under X condition. If both fulfill the requirements, then most likely the cheapest one applies. And if annealed regular PLA suits most every case, then you have to wonder what exactly are these new materials used for?
Gemini can summarize the video for you. Give it the URL.
I really feel like so much of this HT-PLA media spam, is just a marketing grab. I am not saying there are not uses for improved materials etc. But PLA is just not my go too for mechanical parts that need to endure high temps. There are enough other drawbacks that I find in PLA like its UV temperament. Its great for quick recyclable prints, for proof of concept or kids toys/trinkets. But outside of that definitely not my choice plastic anymore.
The point of this product is to give you that choice again. The UV concern is fair enough, but I’ve had regular pla parts out in mega high UV New Zealand sun for years before failure. I do quickly spray paint my parts tho.
I dunno. Printing dimensionally accurate functional parts is difficult enough without introducing randomness during annealing.
Maybe just use ASA or ABS. Buy a cheap but modern printer (Elegoo corexy or a newish Creality bed slinger), build a plywood enclosure for it to control warping and stick it in a outside shed on extension cord so you’re not breathing fumes. Or garage with the door open.
I think it’s all geared for people who can’t. I don’t have an enclosure, don’t really want one, and would prefer to keep my printer on the basement, out of sight as opposed to elsewhere on the house with better ventilation, so this is right up my alley. Fwiw protopasta’s costly htpla-cf anneals rather nicely with minimal warping and looks GREAT, but I’m happy to see some cheaper alternatives, and the video they linked is pretty solid evidence for me as someone who prints primarily functional parts.
The community really needs a set of standardized specs and tests for filaments and resins.
Any manufacturer worth their salt would publish their filament specs.
The community would have something measurable to compare.
Sometimes Y is a lot better than X, but if all you need is X/10 then X is perfectly adequate.
We have ISO standards dictating how plastics should be tested. And Polymaker admitted to not knowing the ISO standards they’re referring to in their TDS and later admitted to purposefully overinflating the numbers to make them look better.
So…it does what the Protopasta HTPLA have been doing for years.
This (the non glass filled version) doesn’t need annealing so no.
Creep under load and lack of temperature resistance are what made me stop using pla. This does not solve the problem with creep.
Now I use petg, which is more UV resistant and still unbelievably cheap. If I really needed high temperature resistance above 85 C I would look to ABS or ASA
Yeah, I’ve found the temperature limits of ordinary PETG to be more than suitable for any application I’d be comfortable using plastic in. Sure I can’t print something in black and leave it under load in the summer sun, but why would I? That’s what metal is for.
As someone who’s been closely following the evolving claims around HT-PLA datasheets, this article hits the nail on the head. The issue isn’t just about whether 60 °C or 70 °C is the right number to quote, it’s about fundamental credibility.
Take Polymaker’s HT-PLA datasheets:
The original TDS v1.0 listed a 0.45 MPa HDT “average” of 69.9 °C, while the graphed curve showed 61.4 °C.
In v1.1, the table was silently revised to list 61.4 °C as the average—no correction notice, no explanation.
Nicolas, Polymaker’s Business Development Lead, later responded to questions by stating:
“There was a mix between: Average Value, Medium Value, Maximum Value.” — AHI Discord, 2025-06-06
Let’s assume that 69.9 °C was a real maximum and 61.4 °C the revised average. That would require the third sample to have been 52.9 °C, implying a 17 °C spread, well beyond the ±5 °C variation limit specified in ISO 75 for semicrystalline polymers.
That leaves three possibilities:
-Polymaker didn’t follow ISO 75 for their HDT results,
-The HDT data was selectively reported or retroactively manipulated,
-Or both.
Worse, the marketing emphasis on a “150 °C heat resistance” value, based solely on Vicat softening point after annealing (Method A/120), is deeply misleading without context. Vicat and HDT are not interchangeable, and the 150 °C claim represents a best-case result under idealized post-processing, not a usable service temperature. For most real-world applications, as-printed HDT is what actually matters, and in this case, it’s barely above 60 °C.
If filament brands like Polymaker want to move beyond cosplay props and into legitimate engineering applications, this kind of selective disclosure and technical ambiguity is not going to cut it. Real engineers need real data, not inflated numbers and retroactive justifications.
I gave up PLA years ago due to it going soft inside the car’s cabin. I now have PETG parts in the engine bay that have been perfect for thousands of miles. PLA is for ornaments.
tldr. You need to anneal your print to get HT.
That’s a no go. Annealing mess the dimension accuracy completely.
The best thing a beginner printer can use is ASA-GF/CF. 100c HDT guaranteed out of box, and with the GF/CF enforcement, no chamber needed until large print.