While I was 3D printing some PLA objects on my Ender 3, I wondered whether 3D printed items are dishwasher safe. I set out to do some research and find out the answer.
Keep on reading for some basic information on this question, as well as some more key details that you’d want to know.
Is 3D Printed PLA Dishwasher Safe?
PLA is not dishwasher safe due to having a low heat resistance. A standard dishwasher reaches temperatures of 60°C (140°F) and the temperature at which PLA starts to soften is 60-70°C. This will lead to deformation and serious warping. Annealing PLA prints can improve heat resistance.
Most 3D printed items, when washed in hot water or with a dishwasher, undergo deformation. Among the different existing 3D printing filaments, PLA is particularly sensitive to heat, making it very unsafe to use with your dishwasher.
At a glass transition temperature of about 60-70°C, PLA usually softens, leading to destruction.
A glass transition temperature refers to the temperature range where a material turns from its rigid version to a soft (but not melted) version, measured by how stiff the material is. This is different to the melting point, and rather leaves the material in a pliable, rubbery state.
Often, different lists can show slight differences in the transition temperature of PLA depending on the brand and manufacturing technique. Either way, there is usually a range to consider.
According to some lists, the transition temperature for PLA is 57°C, while others quote a range of 60-70°C.
It is important to understand that most dishwashers operate at the household water heater temperature, although some control the heat internally. The household water heater temperature has a range of around 55-75°C.
This range of temperature is where PLA glass transition temperature lies and this makes PLA a risky choice for your dishwasher. You may notice the warping and bending of 3D printed PLA when used with your dishwasher.
For this reason, you may want to avoid placing your 3D printed PLA in your dishwasher if you want it to last.
Annealing, the process of increasing temperature to improve firmness, tensile strength, and heat resistance of a given object, can help improve PLA characteristics.
One user said they use HTPLA from Proto Pasta for mugs. This is only after their annealing process of putting the print in the oven, where the mugs can then safely hold rapidly boiling water without softening.
They said they have used it over a fairly long period of time, while putting it in the dishwasher and there is no sign of damage or degradation. They also used a Alumilite Clear Casting Resin to coat the mugs, a food-safe epoxy (FDA approved).
Is 3D Printed ABS Dishwasher Safe?
ABS has great temperature resistance and many people have used it safely in their dishwashers. One person printed a tea filter cup in generic ABS and washes it just fine in a dishwasher. You wouldn’t want to use ABS for food-related items though because it isn’t food-safe.
As stated by several compatibility charts regarding ABS plastic, ABS is considered fairly resistant to the conditions present in the dishwasher, including the temperatures, organic solvents, and alkaline salts.
According to Hutzler, ABS is dishwasher safe.
ABS has a higher glass transition temperature of about 105°C. This property enables it to withstand much higher temperatures before any form of deformation begins.
This deformation breaks down the material, making it deformed and weaker.
Still, the conditions required for the degradation are much higher than that present in the dishwasher.
ABS is very strong and rigid plastic. Unlike PLA and PETG, it has superior hardness and toughness, which make it dishwasher safe.
One user commented that he successfully uses ABS that has been vapor-smoothed safely in their dishwasher.
Is 3D Printed PETG Dishwasher Safe?
PETG is dishwasher safe in terms of the heat resistance, but it definitely can warp at warm temperatures. It has a glass transition temperature of around 75°C so it may withstand dishwasher temperatures for most households, although some may reach near the heat limit, so do watch out for that.
High-grade PETG material has an excellent chemical resistance with a glass transition temperature of about 75°C.
Compared to PLA, this is relatively higher, which means that compared to PLA, most 3D printed PETG is safe for your dishwasher. You can use most dishwashers to clean printed PETG.
It is also fairly easy to print, having a similar level to printing PLA.
However, it is important to consider the temperature of your household heater. Because of its high melting temperature, PETG would probably survive in dishwashers where PLA would melt.
Unfortunately, PETG has a glycol modifier and prevents crystallization which is what annealing requires to improve heat-resistance. ABS cannot be properly annealed either.
One user 3D printed some food-safe PETG wheels for their dishwasher since the old ones were worn out, and they are still going strong after 2 years.
What Filament is Dishwasher Safe?
- Annealed High Temperature PLA
- PETG – lower temperature dishwasher cycle
You want to avoid putting Nylon filament in a dishwasher because it is very prone to moisture, though a 3D print with thick walls and very high infill can sustain a cool wash in a dishwasher.
HIPS filament will definitely melt in a dishwasher, adding that it is water-soluble and has low temperature resistance.
Definitely avoid placing any kind of carbon fiber 3D prints in a dishwasher because it can warp and clog the moving parts.
Flexible filament isn’t going to stand up well in a dishwasher due to already being really soft and warps under much lower heats.
Best Filament for Microwave Use – Safe 3D Printing
Is PLA Microwave Safe?
PLA is microwave safe depending on the brand and how it was manufactured. One user who ran tests on PLA found that there was no raise in temperature after 1 minute in the microwave, using plain PLA, black PLA, and green-tinted PLA. PLA can absorb water which can then be heated up by the microwaves.
Most people would say to avoid using PLA in the microwave, especially if you are using it for food because it has the opportunity to pick up bacteria through the layer lines and micropores.
Is PETG Microwave Safe?
PETG is transparent to microwaves and has a high enough heat-resistance to sufficiently deal with microwave applications. PETP is the normal plastic within the group that is used for bottles and injection molding, but PETG still holds up very well.