My microwave has a glass plate that sits on this round disk with some wheels that holds the glass plate as it turns. The round disk broke. I want to design and print a new one. Does anyone know which Bambu Filament I should use to print that?
First, this question has been asked before regarding 3D-printed objects coming into contact with food. In short, it’s a very bad idea.
To answer your question: There is NO Bambu filament suitable for this application. While materials like PC, PETG, and ABS can theoretically be used to create a microwavable vessel (e.g., a cup), this application requires much more than just choosing the right filament. Personally, I wouldn’t trust anything poured into such a vessel and certainly wouldn’t drink anything from it.
________________________________________________________
There is a saying: “When the only tool in your toolbox is a hammer, all the world looks like a nail.” You got your 3D printer, and suddenly, you fall into what I like to call “Star Trek replicator syndrome,” thinking, “Hey, I don’t have to buy that; I can print it.” That’s a common pitfall we’ve all fallen into because we so badly want to find uses for our new printer and often fail to ask not whether we could, but whether we should. This topic is one where one clearly shouldn’t.
Safety
Now, onto safety concerns. FDM printing is far from watertight unless post-processed and sealed using methods like annealing or an epoxy coating. Sure, it can hold liquid but so can a paper cup. Additionally, you’d want a USDA-certified filament that is free from hazardous chemicals and resistant to microbial growth. Finding a filament that is both USDA-certified and microwave-safe would be a challenge—but perhaps some company has managed it. Here’s an article on food safety and 3D filament: The Essential Guide to Food Safe 3D Printing | Formlabs
But food safety is only part of the issue. Since FDM prints rarely achieve 100% watertight layer adhesion, microscopic gaps remain unless printed under specific conditions and sealed properly. These gaps can harbor microbial growth and trap moisture, creating additional hazards—such as the risk of the plastic exploding as trapped water rapidly turns to steam.
There’s a reason microwave turntable plates are made of glass: it’s sealed, safe, durable, easy to clean, and won’t explode from internal moisture buildup.
That said, a few polypropylene filaments, such as FormFutura’s Centaur PP ($60+ per 1KG), advertise suitability for microwavable objects. However, I found none that explicitly claim to be both food-safe and microwave-safe. Also, at that price, why bother printing a replacement plate when a glass one costs around $20 and is SAFE?
4 Likes
When I read the question, I didn’t expect any useful filament to come up. You proved me wrong, Olias 
I think the part won’t come into contact with food, it’s just the bearing below the glass turn table. Your suggestion seems like a viable option then.
Perhaps that could be true regarding food safety. However, the notion of spending $36 on something you can buy a better version of for $20 still doesn’t pass the common sense test. Plus, I would think that any splattered food contaminating the surface of a filament, even PP, would get baked in, causing other issues, the worst of which would be a plain gross-looking appearance after a few uses. We all know, for example, how easily tomato sauce sticks to and stains plastic.
But this would be an interesting experiment if someone were inclined to spend nine hours of print time, assuming 100% infill, which puts it at 600g, by the way.
However, when I ran a hypothetical model to compute those nine hours, it was based on a 10mm-high plate. One thing we all overlook here is that the build plate max is 250mm, or roughly 10". So, assuming an average microwave has a plate between 9" and 12.5", there is the practical matter that the build plate may not be large enough.
Yes, that is what I would like to design and print. Reading the question so you can give a good answer is always preferred in forums. It has almost got to the point I don’t want to post anything anywhere anymore because people don’t read and they are stuck in their ways.
I know I can buy this cheaper, but I like a challenge and wanted to challenge myself to doing this. I am not wasting your time, I am enriching mine!
@Olias thank you for the comments but they were not helpful.
1 Like
if you were to print it I would suggest petg (or maybe nylon if it isn’t toxic), abs/asa will make toxic fumes when hot.
I would be careful with that suggestion. Some polymers absorb the microwaves and will do nasty things. That is the reason why only some plastic dishes are suitable for use in microwaves. As Olias mentioned PP, I think every dish I have seen that is explicitly designated as useable in a microwave has been made from PP. If there is a filament that claims to be useable in microwaves, I wouldn’t search any longer.
1 Like