Help: High Outdoor Temperatures Are Melting My 3D Prints

[JJTechPrints]

I’m working on creating name tags for the plants in my garden. I initially printed some in PLA, but they bent over within the first few days. So, I switched to PETG, which held up through some hot days—until one particularly scorching day.

I’m located in South Texas, USA, where the temperatures have been reaching 111°F (44°C). Since noticing the deformed models, I started taking ground surface temperature measurements around 1 PM, and I’ve recorded a max of 158°F (70°C) on the ground, although I’ve only sampled a couple of days so far.

Are there any printable plastics that can withstand these high temperatures? I’ve been considering ABS, but I currently only own an A1 Mini and understand that printing ABS requires an enclosed printer like the P1S or X1C. How dangerous are the fumes from ABS? I work in a small space—half of a shed converted into my “tinker shed”—with an air quality monitor and a window AC system that cycles the air. Would I need to drill air vents to safely print ABS and vent the fumes outside?

Any advice would be greatly appreciated.

It’s late now, but I’ll try to post a picture of my fallen plant name tags—they look like they’re just resting on the ground, taking a break.

[MalcTheOracle]

ASA is better suited to external use as it is less affected by infrared.

• Extraordinary UV Resistance
• Exceptional Temperature Resistance
• High Impact Strength and Durability
• Outdoor Use for Long-Term Purpose
• Comes with High Temperature Reusable Spool

ASA

The problem is that you require an enclosed printer like the P or X series. You say you own an A1 mini, great printer I own one as well as a couple of P1S’s.

Printing with ABS is less about the fumes as this isn’t as much a problem as it used to be and more it’s need to have a very warm environment and a constant temperature without any drafts. This again really requires an enclosure for anything but the smallest of prints.

[RocketSled]

Printing ABS or ASA does not require an enclosed printer. Larger prints do tend to warp, and successful printing requires careful temperature management (like, don’t have the airconditioner blowing cold air around the room). I printed with ABS almost exclusively back in 2010 on my Makerbot which was not enclosed.

For smaller, flatter prints like plant name tags, ABS/ASA should be fairly easy to print successfully. Just crank the build plate temp all the way up and run the lowest extrusion temp you can (requires doing a temp tower cal). No fans.

[SupportAssistant]

We recommend checking our Bambu Lab Filament Guide to learn more about the filaments based on your application.

Ultimate 3D Printer Filament Guide | Bambu Lab

ASA, as the other users mentioned above could be a great option.

[JJTechPrints]

Thank you for the quick feedback, @MalcTheOracle, @RocketSled, and @SupportAssistant

As promised, here’s a picture of my poor plant tags. From left to right: The red and green one is PLA, the black and green one is a mix of PETG and PLA (which is why there’s a missing letter—another lesson learned), and finally, the red and white one is PLA, placed there to show how the tags should be standing in the soil.

I’ll be ordering some ASA soon and revisiting my Hydroponic Seed to Soil Name Tags project to add an ASA profile.

Thanks again!

[user_2786951938]

I use ASA but you should be aware that heating ASA releases styrene and acrylonitrile VOC’s. Not trying to be alarmist, here is a graph of the VOC release and links to the SDS’ for each: Styrene SDS https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1045AppA

Make up your own mind on how to handle it. Personally I only print ASA and ABS on a printer with an enclosure which has fan exhaust to the outdoors.

[user_3026326371]

For harsh outdoor conditions I prefer Nylon.
Not always that easy to print but rather durable, even in the Australian summer sun.
Some colours do fade with the UV though for some reason.
I think they literally degrade inside the nylon…

[Ukdavewood]

Colour also worth factoring into the mix. I think more reflective / brighter colours or white tend to hold up a bit better than black for example.

[user_3026326371]

Not really if the main issue is heat from the ground.
Take some prints and your dashboard on a hot summer’s day…
If you want to keep the sun away a clear coat that blocks UV works just fine but it won’t fix the temp of the environment.

Ever seen a road bleed and felt a bit stuck when you had to stop?
Quite common around here during the summer.
The road gets so hot in the sun that the moving wheels compress the bitumen out of the gravel that makes the asphalt - the road bleeds.
Really funny to see barefoot tourists coming from the beach trying to cross the road to snatch a drink or snack in a cafe across the road…
Some managed to end up with burns…

A filament not good enough for at least 80 degrees Celsius before starting to get soft won’t give you joy for outdoor use during the Aussie summer.
And if it gets a lot of sun you want something that tolerates even more.
For little signs and such I won’t use my printer, I use the laser cutter or cast some Pweter/Aluminium if things are meant to last outdoors.

[Alex_vG]

I think ABS and ASA could already be on the border with those temperatures measured. I would rather look at PC. which goes far beyond both regarding temperature resistance. Those flat batches should be no problem without enclosure.

[Tistrue]

Try again with lighter colors (white with colored letters).

[JJTechPrints]

Update: How I Made Regular PLA Objects Withstand High Outdoor Temperatures

After extensive research and experimentation, I’ve found a way to improve the heat resistance of regular PLA filament for use in high-heat environments. The key is a method called water boil annealing.

Best and Easiest Method → The 80°C Water Boil Annealing Process:

1. Place your PLA objects into a pot of cold water.
2. Use something like a fryer basket to keep the objects submerged.
3. Add a water temperature monitor.
4. Slowly heat the water to 80°C (176°F).
5. Once it reaches 80°C, turn off the heat and let the water cool naturally to around 38°C (100°F) before removing the objects.

Reference: Huge thanks to this video for showing me the 80°C method.

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Originally, I tried this in a regular cooking pot on our stove, much to my wife’s dismay.

Next, I set up a torture test with two annealed plant tags and two regular PLA plant tags to see how they would hold up. The annealed tags are the closer two. Note the vertical tag has a slight deformation from the annealing process. The regular PLA tags are the furthest away.

In less than an hour, the horizontal PLA plant tag had already deformed. Surface temps were hitting 77C (170F).

Over the next few days, I monitored the surface temperature with my trusty temperature gun and took pictures of the plant tags for comparison.

24 hours later

4 days later

Interestingly, the vertical untreated PLA plant tag didn’t noticeably deform. It seems that, with minimal wind, the plastic may have naturally annealed over time.

To keep the peace at home, I invested in an electric burner and a 10 QT cooking pot with a basket. Now, I can anneal multiple objects at once, outside. The electric burner heats the pot slowly enough to prevent drastic temperature changes, which is crucial for avoiding deformation.

I use this temperature gauge to alert me when the water hits 80°C.

Annealing process timings with this electric burner and cooking pot:

• 30 mins: Half-filled pot reaching 80°C. Electric burner set to Max
• 1 hour: Water cooling down to around 37-38°C.

Total time: 1 hour and 30 mins

Finally, I plan on coating these annealed prints in this UV protection spray to prevent color fading.

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This process works well for the objects I plan to use in my backyard, allowing me to make use of the various PLA colors I’ve accumulated. It also saves me from needing to invest in an enclosed printer, a full set of ASA filament, and modifying my workspace to vent harmful fumes.

Once I upgrade to an enclosed printer with proper ventilation, I’ll switch to ASA for high-precision projects where any slight deformation from annealing PLA wouldn’t be acceptable.

I hope this guide helps anyone in a similar situation. Happy printing!

[user_3026326371]

Two things to note though:
The boiling will make the PLA absorb a lot of water, which changes the properties of the material.
Annealing of plastic is usually done DRY, like in sand, baking powder or such.

It would be interesting though to see how the printed parts perform ONCE FULLY DRIED.