Reflowing With A Hair Straightener

final

Around here, reflow ovens usually mean a toaster oven, and if you’re exceptionally cool, a thermistor and PID controller. There are, of course, a thousand ways to turn solder paste into a solid connection and [Saar] might have found the cheapest way yet: a hair straightener with a street value of just £15.

We don’t expect the majority of the Hackaday demographic to know much about hair straighteners, but [Saar] has done all the work and came up with a list of what makes a good one. Floating plates are a must to keep the PCB in contact with the heating element at all times, and temperature control is essential. [Saar] ended up with a Remington S3500 Ceramic Straight 230 Hair Straightener, although a trip to any big box store should yield a straightener that would work just as well.

One modification [Saar] added was a strip of Kapton tape to one of the ceramic heating elements. It’s not a replacement for a toaster oven or real reflow oven, but for small boards it works just as well.

Video below.

34 thoughts on “Reflowing With A Hair Straightener

  1. A nice hack, especially as toaster ovens aren’t that common here in the UK. Also, as a man who has a thing for women with curly hair, the more of these evil devices that are taken off the streets the better!

    Oddly enough I found a 9L 1kW toaster oven in Robert Dyas today for £18 which looks like it might have potential.

      1. If it is just passives like in the OP picture, it wouldn’t take much more to solder them as you place them down. You can even use solder paste if you like.

        On the other hand, if they are fine pitch or BGA parts, a reflow oven with the correct temperature profile would be much better.

    1. So how do you do double sided SMT with a skillet when the bottom side is populated?

      In an oven, the bottom parts are held by surface tension. (Heavy parts without sufficient pads needed to be glued down or should be located on the “top” side that is populated last.)

    1. Make it eject like your favorite disc player when done. Just make sure it doesn’t jolt the board, I would imagine. Note that I’m just adding an idea, I’ve never reflowed before!

  2. Forget about soldering SMDs, this could be great for desoldering DIP ICs for salvage!

    I just tried my soldering iron at about 230C (actually the temp guage and the temp pot show different readings in the low range, but hopefully it was close) and leaded solder melts after a while with the iron on the board. Lead-free solder doesn’t, but if you dope it with a bit of leaded stuff before hand, it melts fine.

    I almost bought a solder pot a while back for desoldering (and thought of making my own heating element) – this should be perfect!

    At the end of the week, I’ll have a look ’round the Op-Shops and hopefuly grab a few old ones, with a bit of luck some will get hotter than 240C after being left on a while.

    Should be able to disconnect the upper part so you just end up with a couple of “heat wands”.

    1. Probably won’t work very well, as the heating element is flat, and through hole components are uneven. If you don’t care about the board, and the pins are straight, just heat the board over a gas stove until solder is melted, and then quickly flip the board over and tap it on something so that the components will fall out. Or, similarly, hold the board upside down, and use a hot air gun (paint stripper) to melt the solder.

      1. DIP pins aren’t uneven, unless someone has tried to cut the ends off (I’m talking about commercial boards, so they haven’t).

        Might need to straighten the pins if bent, that’s all. Anyhow, I’ll give it a go and see.

        Having experanced melting PCB fumes/residue, I really wouldn’t want to be exposing a board to flame anywhere near something that had half a chance of going near food.

  3. One good thing with the hair irons is that many of them let you set the temperature. Mine goes from 360F to 440F in increments of 20 degrees. But I wouldn’t want to use mine for reflow. They really aren’t built to sit flat and level; mine would require a clamp or something. And secondly my roommate has a hot air reflow gun

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.