Duct tape is supposed to be the ultimate fixer for all your handiwork problems, but it has limitations. Unfortunately, these make it less useful for some tasks than others, and it means that there are certain things that you cannot solve with duct tape.
Any use involving putting duct tape in the microwave, for example, is not going to end well.
Duct tape does not have a high enough temperature rating for microwaves. Its limit is 140 ℉, while microwaves can reach as high as 212 ℉ and tend to operate in their higher ranges. This will melt the adhesive, undoing the repair, and can lead to other dangers and unwanted outcomes.
Duct Tape Cannot Withstand High Temperatures
Typically, duct tape has a pretty low temperature rating. This is because it was designed as a water and shear-resistant tape for sealing military packages in World War II; heat was not much of a consideration in the design.
Most duct tapes are rated for temperatures under 140 ℉. Once the temperature of duct tape reaches and exceeds this limit, the adhesive begins to melt and lose its tackiness. The tape will then start to slide and peel away.
This is actually why you shouldn’t use duct tape on ducts. It was once used in this way as a very temporary fix (which is where the name came from).
However, it is no longer considered appropriate for your HVAC system or dryer ducts because ducts frequently get hot enough to compromise the tape’s bond and efficacy.
Now, if ducts reach around the 140 ℉ limit that duct tape has, imagine how poorly the tape will work within a microwave that can achieve and sustain much higher temperatures.
Microwaves Get Too Hot for Duct Tape
Microwaves get much hotter than ducts. The average microwave can reach around 212 ℉, far beyond what duct tape can withstand. Even specialized versions of Duck Tape (a branded version of duct tape) with higher temperature ratings are capped at 200 ℉.
However, the higher temperatures of a microwave can compromise more than the tape’s stickiness and durability (which is only ever temporary to start). There are other safety factors to consider that make it a poor choice for your microwave.
Another big reason the building code prohibits duct tape for HVAC applications is that it degenerates with heat, quickly failing, and the cloth within is flammable.
Exposing the tape to temperatures above its manufactured rating is risky as you can never guarantee it won’t ignite, even if the chances are supposed to be low with the plastic film.
So, duct tape won’t do well with high temperatures, and things will start going wrong.
Now, while 30 seconds in the microwave heat might be okay if you are warming food in a container sealed with duct tape, you never know the point at which it is no longer okay.
Furthermore, microwaves can also sustain high temperatures throughout their running time, which only increases the risks.
Since it’s impractical to limit your microwave usage to a few seconds, there is no point in repairing your microwave with this tape. Instead, you should buy a new microwave or use appropriately rated materials for a safe repair.
Dangers of Putting Duct Tape in the Microwave
There are also other dangers and risks associated with exposing the tape to the high temperatures of a microwave:
- While the rubber and plastic of the tape aren’t as likely to catch fire, they can still burn. By heating the tape, it will start to degrade and disintegrate. This can release fumes and particles you don’t want seeping into your food. Plastic and rubber aren’t meant to be consumed.
- The mess of glue getting everywhere as it melts will not be fun to clean up, and you will likely have to do so if you want to attempt another repair since duct tape is notorious for leaving residue behind.
- The melting adhesive may not be as sticky as usual, but it can melt and clog up the moving parts and cause blockage for things like the heat source and vents. I don’t think unnecessarily interfering with an appliance’s functioning is a good plan.
So, using duct tape in a microwave is not feasible as whatever you try to repair won’t stay sealed for long.
It is particularly unwise to try and cover or repair any wiring in the appliance as this won’t stay sealed. Duct tape is not on par with proper electrician’s tape and will only melt away, leaving a mess of the wires and a health hazard for you to deal with.
There are better HVAC or industrial-grade tapes that will be a safer option for fixing the microwave as they are listed for these higher temperatures. There are also other tapes that are better for short-term use in the microwave.