I'm currently in the middle of redesigning the mini toolkit which I use regularly for a lot of my work, and I wanted to show you a little project from it.

Being quite fond of the cheap USB soldering irons, I wanted to update it and add a USB-C socket to the back.


For how inexpensive they are, and their worldwide availability, I think these irons are pretty decent. If you're doing a lot of work or something more intricate you might need something more powerful, but for a lot of small, quick tasks it does the job well enough.

It's so light and small that I can take it with me, say if I'm reparing something around the house, and because it's USB powered, I can power it multiple ways, through a charger, powerbank or a computer's USB port.

The only thing I'm not as fond of is the USB to 3.5mm cable which is required to power it. I don't use this cable for anything else, and that's why I wanted to switch it with a USB-C one.


I was originally planning on taking the iron apart, removing the 3.5mm socket and replacing it all manually, then I was going to design a 3D printed case and all the rest, but I realized it's much simpler to just add USB-C using a custom adapter, so I scrapped my initial plans and made one.

This little thing has it's own 3.5mm jack and simply plugs into the back of the iron, routing the 5V and GND through USB-C socket.

The two main components needed are firstly a USB-C breakout board. If you're going to make your own, find one that looks just like this, as there are many variations. This one has 4 contacts on the back. Just search for USB-C female breakout.

The other component is the 3.5mm 2 or 3 pole jack. These are also generic, so when you search, use keywords like "3 Pole Male Plug 3.5mm Solder" and hopefully it'll pop up. I just used one I already had on hand, so if you can't find the exact one, you may need to redesign the 3D printed collar so it holds the jack snugly.

Inside is straightforward, just cut down the contacts at the end of the jack, and solder two wires to it. You only need the 2 pins for the 5V and GND, as indicated here, so you can remove the other one if you have a 3 pole jack. Once complete, solder the other end of the wires to the 5V and GND contacts on the breakout board. You can add a bit of electrical tape or glue to the stop any potential shorts when it's put in the case.

After that you glue the collar around the jack, place the USB-C breakout and wires into the case, and screw the top on using 2x M1.4 x 6mm screws. Once the collar and jack is screwed in it holds everything in place.


I think that's all there is to say about it. The adapter is simple and does the job. I intend to just leave it on the end of my iron from now on. I also went a bit further and painted the case black just to finish it off, and I'm very pleased with the result.

If you want to make your own the source files are linked in the description. I'm guessing a few of you have one of these, so hopefully it's useful.


Just wanted to mention a couple things at the end of the video. Firstly, thank you to all the people who have been reading since it launched a couple weeks ago. I appreciate all the feedback and glad you seem to like it.

I've also added a new Simulation Grid tee design to the shop, so pick one up if you like it and want to support the site/channel.

I’m also looking for a front end web developer to collab with on an open source HTML template project. It’ll be a free resource for designers/engineers/makers. If you want to help build something great, send portfolios/github links to:

Alright that's it, thanks again for everything. I've got a lot planned for this year, so stay tuned. I'll see you in the next video, bye.


Download the source files HERE