Notifications
Clear all

Printed parts IN Microwaves?  

  RSS
JMcK
 JMcK
(@jmck)
Reputable Member
Printed parts IN Microwaves?

Is there some filament material type that can safely live INSIDE a microwave oven?

My oven has this little wheeled ring that goes UNDER the glass turntable. That ring slides out of position when you even look at it funny. So I'd like to design some sort of stabilizer, but I'd obviously need something that doesn't get melty or release gasses when microwaved. Sounds like PLA a definite no, but I'm seeing indications PETG might be a maybe?

When someone asks you if you're a god, you say, "YES!"

Posted : 16/04/2022 4:53 pm
Artur5
(@artur5)
Estimable Member
RE: Printed parts IN Microwaves?

Back in the day I used to refill inkjet cartridges of the kind that have a sponge inside. Sometimes they needed to be flushed with water in order to clean dried ink inside. Then, before refilling the cart again you have to dry the sponge. If it’s wet, it won’t absorb ink very well. Some people uses vacuum to get rid of the humidity, others just ‘patience’ but I did it with the microwave, leaving the carts there for less than a minute at minimal power setting. This way the sponge dried much faster..

The sponge, made of fiber, and the water absorbed microwaves, but the body of the cartridge made of translucent plastic seemed to ignore them. The part that wasn’t in contact with the sponge came out cold after ‘microwavin’ the cart.

I’m not sure what type of plastic is used for those carts. To me looks like polypropylene, buy I may be totally wrong. No idea either if plastics in general behave likewise regarding this matter.  Of course, if the part you intend to print comes in contact with something that absorbs microwaves it will become hot, in spite of not absorbing them. I’d forget about PLA and probably PETg . Other plastics more heat resilient might emit fumes when heated (ABS ?)

Unless somebody with good knowledge of this question pops here to enlighten us, it’s up to you ( trial and error.. ) but be very, very  careful on what you do with your microwave oven, Not so much  for possible damage to the appliance but for your safety and health.

Posted : 16/04/2022 6:15 pm
jsw
 jsw
(@jsw)
Famed Member
RE:

What I would do is make some test prints using the filament(s) you would like to use for the project.

Then 'nuke' the test pieces, at least to start in a microwave-safe dish, and see if they appreciably warm up when under the beam.  An infrared thermometer (like the ones used to measure 3d print bed temperatures) can tell if they are warming.

If I were doing this, I would at least start with a white or better a so-called transparent filament, something with as few additives as is possible.  We have a set of 'microwave safe' plastic dishes (I think the Rubbermaid brand) which hold up fine in the u-wave.  I'm not sure what plastic these are, but they do not melt or deform.  We also store left-overs occasionally in various plastic single-use containers and warm them up in the u-wave without issue.

Posted : 16/04/2022 7:48 pm
senexfaciens
(@senexfaciens)
Active Member
RE: Printed parts IN Microwaves?

Disclaimer: I am not a scientist. 

Microwave ovens work by heating the water inside the food, cooking them from the inside out.  The same would be true of your plastics.  So, that means you need to use a plastic with no water in it, and wouldn't absorb any.  Obviously, PLA is out because it's well known to absorb water from the humidity in the air.  PETG and ABS are hydrophobic, so if it was my experiment, I would start there and do what jsw suggests.

Posted : 16/04/2022 8:46 pm
corycwagner
(@corycwagner)
Active Member
RE: Printed parts IN Microwaves?

What you wrote, senexfaciens, just lit a lightbulb.  Based on what you are saying, do you think one could use a microwave to dry-out old pla filament?  It sure would be faster than putting it in the oven. I'll need to research a way to test this.

Posted : 19/04/2022 3:26 pm
JMcK
 JMcK
(@jmck)
Reputable Member
Topic starter answered:
RE: Printed parts IN Microwaves?

Microwaves would heat the water to steam, which would melt the PLA (or just soften depending on how much it has absorbed). Most dehydrators work at temperatures less hot than steam, so the water evaporates which is not the same. And yes, is much slower.

When someone asks you if you're a god, you say, "YES!"

Posted : 19/04/2022 3:59 pm
MileHigh3Der
(@milehigh3der)
Reputable Member
RE: Printed parts IN Microwaves?

Un-pigmented is where I would start.  You might have to make a mold and then use that to make a part.  All the plastics we use in printers are thermoplastic.  Heat them up and the start to flow.  Thermoset chemically react and won’t remelt.

So maybe print a mold and then use an epoxy/amine two-part putty to make the part?  Those parts would survive higher temps than PETG or even PC.  In general.  There are so many different reactive chemistries you could use.

Posted : 20/04/2022 4:10 am
JMcK
 JMcK
(@jmck)
Reputable Member
Topic starter answered:
RE: Printed parts IN Microwaves?

Posted by: @milehigh3der

Un-pigmented is where I would start.  You might have to make a mold and then use that to make a part.  All the plastics we use in printers are thermoplastic.  Heat them up and the start to flow.  Thermoset chemically react and won’t remelt.

So maybe print a mold and then use an epoxy/amine two-part putty to make the part?  Those parts would survive higher temps than PETG or even PC.  In general.  There are so many different reactive chemistries you could use.

This gives me a whole new avenue of exploration... I like this idea.

When someone asks you if you're a god, you say, "YES!"

Posted : 20/04/2022 9:54 am
Share: