Photos - finally built soldering station :)

I have spent the last two days in the shed, mostly making the case for my home brew soldering station. The base is chipboard, the sides are plywood, the top is steel, the back panel is hardboard, the front panel is some plastic that I salvaged from a discarded shop sign about 12 years ago. Finally found a use for it! The stand on top is made from wire I got from a divan bed base. Tough tensile stuff, had to use blowlamp to bend it around...

Notice the sponge tray swivels out. This isn't ingenious design, it's completely forgetting to include it and having to find a way to make it fit! Worked out ok though. If I'd actually thought the sponge tray design through it would have been rather better :/

Inside the box is the pid controller and an isolation transformer which came from an old shaver socket.

The brass coloured eyelet is the sort you use for clothing. I put a rubber sleeve on the soldering iron's cable to give a bit of strain relief. At the back is an IEC mains socket I pulled from something a long time ago...

The thermocouple is shielded, and came with a metal "button" and nut on the end. I carefully filed the edges of where the button was crimped on so I could split it open and remove it, revealing the twisted wires inside. I trimmed back the shield a little bit, made a little oval hole in the soldering iron's sleeve and poked the tc end in. Since I had to take it apart a couple of times it got harder to reassemble due to the insulation fraying... The tc is squashed up with the bit at the end of the sleeve.

The metal ring round the barrel of the iron is the stem of a blind rivet I bent round to hold the tc wire in place. Ok I could have made something nicer but wanted to try it out soon!

The iron's handle is actually light blue - that's black tape around it. I wanted to thread the tc wire up inside but there's too much to go wrong by doing that.

Temperature appears accurate - only 2 or 3 degrees different from the reading on my multimeter - which I recalibrated myself last year so is probably suspect anyway (but better than it would have been...) Solder just melts when it's set to 250. There's some overshoot - I haven't set up the controller yet, so expect to improve that. I tried setting the controller to 400 to see if the iron would get that hot, and it does - so I don't know what it would get up to without the controller.

So now I just need to find stuff to solder...

Now if you had a CD drive, you could add a cup holder

Just Kidding

Nice Project!

Wow, very nicely done! Where did you get the electronics? Are they salvaged from another soldering station, ore did you build this thing from scratch?

Built from scratch - "the electronics" consists of a PID controller bought off eBay

I find those CD drive cup holders to be too flimsy unless you have a skinny cup - in which case it falls through the hole! Useless!

Hi thobscottle

I admire your energy for stuff like this

Being in the Tv repair game for a living I tend to throw iron's away that don't work properly anymore....never mind building stuff like you. May your love of Electronics stay with you forever.

May your hobby never become your main source of income..like me

Love goes out the window and practicality comes boss. Then you become Focused to an extent that makes people around you try and THINK.....because they cannot be ever be as driven and accurate as you. Nothing less than absolute dedication to the job on the bench to be done properly.

Not the right words...but anyway I am getting through to people. Everything I do, I do to the best of my ability. And that is what I am trying to pass on to people here where I live. I don't know everything. I have lots to learn too. But, I don't take chances.....If I am not sure...I ask questions.

Sorry throbscottle for taking over your thread

Please continue Buddy where you left off

As always,
tvtech

Funny, I always wanted to work in electronics in some way. But the more I hang around here the more I wonder if I should be glad I never did...

Hi,

Very nice project there, and nicely done too. And thanks for the pics as they tell the whole story.
I always wanted to do a project like this but never got around to it. Friend bought a hot air rework station but it was quite expensive, so i didnt really want to go that route. Building one is more fun anyway

It really was mostly joinery though!

Whilst building this I measured the current draw of the iron - only about 45mA rms according to my cheap meter. Considering the iron has a diode in series with the element so it is only effectively getting 120V, surely the current should be nearly 10 times this (it's supposed to be a 40W iron). What's going on?

The 40W value is the max for times when the element is on 100%. To maintain temperature when sitting, the PWM will reduce right down and only use a fraction of the wattage.

Of the power usage you mentioned, much of that may be going to the PID controller to run it and its displays.

If you want to measure full element wattage, measure during the first 5 or 10 seconds after a cold turn-on. The element will be on 100% then.

Nice job. Funny waveforms are difficult to measure accurately. Look at the input power of the entire thing and the input power of just the PID controller and subtract.

Sine waves at line frequency you can measure.

Oh, this was just the iron itself running direct from the mains! Still, it seems a big error even accounting for the diode in the iron - works out about 4.5W

hmmm that can't be right, either your meter is not working correctly or your soldering iron is kaput or measuring method is wrong.
btw, what are the diodes for?

It's a very cheap iron with a 110V element sold for use on 240V, so they put a diode in to stop half the cycles.

I suspect the meter is wrong - I just connected it in series with the iron, which certainly isn't kaput!

Well, today is a sad day. It was a very cheap iron after all, and the element didn't last very long Ordered a replacement element - which is supposed to be correct voltage.