Microwavable Soldering Iron (30 sec microwaving)

Did you ever wonder why there's no such thing as a microwavable soldering iron?

Well, now there is.

It's cordless, yet it doesn’t require gas or battery power to work.

Simply microwave it for 30 seconds (depending on how hot you want it, the power of the microwave, etc.), and it's ready for a quick soldering job.

Let’s say you need to solder a cable that broke off from a switch—this soldering iron will do the job.

But why does it even exist?

I made it because I needed to solder something six years ago, but there was nowhere to plug in a soldering iron, and I didn’t have a cordless one.

Since I was experimenting with microwave metal melting, it occurred to me that the same principle could be applied to make a soldering iron. I initially ignored the idea because it seemed ridiculous, but over time, it grew on me.

So I made it—and it's great.

Why not just use a battery-operated or gas-powered soldering iron?

Those are great, and I use them all the time. This soldering iron isn’t meant to replace them.

I made it simply because I love cordless tools. However, cordless soldering irons have one downside: you can forget to buy gas or charge them.

Since this soldering iron is heated in a microwave, you’ll never find yourself needing to recharge it or refill gas. The only thing you need is a microwave—probably the one in your kitchen.

This is a working prototype, not necessarily a final product.

It works, but I already see ways to improve it and make it much, much better. However, I don’t know if that's something I want to do. I might be the only one who finds a microwavable soldering iron appealing, so I didn’t want to spend more time than necessary perfecting something that I’m not sure people will find useful.

Watch the video to see how to make it.

I printed the shell using Siraya Tech Sculpt Grey resin, which is highly heat-resistant. They also have a white version that can withstand even higher temperatures, but I haven’t tried it yet.

I also don’t know if it’s the best resin for the job, as I haven’t conducted longevity tests. It works for now and can handle the heat, but I’m not sure whether it will crack over time.

As for printing the shell with an FDM printer, I haven’t tried any high-temperature filaments. PLA or PETG won’t work, but I do print the handle and the shell’s lid in PLA—just not the shell itself.

What you’ll need:

• 900M soldering iron tip
• 10g of fine silicon carbide
• A strip of ceramic fiber sheet
• Sodium silicate (water-glass)
• Some Kapton tape
• (Optional: some boric acid)

Silicon carbide absorbs microwaves and heats up—that’s how it works.

Microwave arcing issues?

I haven’t observed any problems with this design, but depending on your microwave or the soldering iron tip, arcing might occur.

In the video, I didn’t fully embed the silicon carbide heating element into the ceramic fiber, but you can if you want.

What’s the difference?

• A fully embedded heating element heats up faster and reaches higher temperatures but is also easier to overheat.
• If you don’t embed it as much, it will still get hot but not necessarily glowing red—though this also depends on your microwave.

Finally, you can make this without any 3D printing—just wrap the heating element in ceramic fiber. However, by printing it, you can make it look more like a traditional soldering iron and have a proper handle