DIY Soldering Station

[shobo]

Hi all,

I want to build myself a nice skookum soldering station.
So the first thing i bought was an iron,a 936 clone from Atten and the second was a 70 w power supply (24v/2.9A).Feature wise i would like to use one of them 128*64 ST7920 as a display and a rotary encoder and a few buttons to interface with it.

I know,chinesium grade irons are crap but at the moment i cant get my hands on a nice Weller PES51 (i like the design of it).

So,my cry for help is:

- since i am just starting electronics as a hobby i don't really know how to fabricobble something together yet make something that actually works.So if someone could actually help me with it that would be nice

Just so you know,i have some knowledge of basic stuff.

[gildasd]

Google translates into AvEism now?

The first order of business should be some research:
- How much power does a soldering iron actually use?
- is the heat measured directly or indirectly and calculated?
- the stuff you already have, measure and document voltages/watts/ resistance, try to reverse engineer a schematic.

They try to lay out a basic plan of how the parts work with one another, with this info, the forum greybeards will be able to tell you you are doing it all wrong 

[Fire Doger]

The first thing that you have to do is to build it in your mind. It is hard but that's how the questions about building it will arise.

Lets take for example your soldering idea.
1. You need power
2. You have to read the temperature
3. You have to control the power according to temperature
4. You need some way to interface with the user.

Now lets start building each part.
1: How to calculate how much power do I need? (Depends on heating element and control circuit)
What voltage do I need? (one value depends on heating element and the others to control circuit)

2. Does your iron have integrated sensor?
If yes what type? PTC, NTC, Thermocouple?
According to this you know what circuit you will need to transform sensor output to a value that mC can handle.
For example you can amplify it, you digitize it and send it with SPI, I2C etc...

3. How you want to control it? With MOS, Triac, SSR?
What control method do you want to use? something easy like On-Off, something more complex like PID or something extreme like Model Predictive?

4. You already choose what you want, cool

How to start building it.
A. Separate it to individual blocks
B. Test each block if behaves as you would like
C. Debug them
D. Combine them

For your application the blocks are:
Controlling heating element
Reading Temperature
Controlling screen
Get input from rotary encoder.

Lets view temperature measurement:
You make a circuit and feeding it on mC which displays it to Serial for ex.
Does mC readings match nozzle temperature? there is steady state error or error goes higher on higher temperatures?
Is temperature accuracy enough for your application?
If you have problems you start solving them 1 by 1.

Lets see screen.
Can you make your mC to display something on this screen?
Can you design your UI on this screen?
How it will look like?
Does screen needs too many pins from mC?

And you continue with the rest.
There are tons of DIY soldering irons on the web, you can build an iron better than the most expensive if you choose carefully what you gonna use and why. Try to act like Dave when he was designing uCurrent

PS. It is very important to make a full plan on your mind. With experience you will be able to make better plans but you need practice on that.
Good luck!

[Kalvin]

Start with something that is already done:

https://create.arduino.cc/projecthub/sfrwmaker/soldering-iron-controller-for-hakko-907-8c5866
http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=6302

Study how they work, build something, test. Develop your own. Or buy something simple and cheap from eBay and modify it for your own purposes. Go to eBay and enter "digital soldering iron controller hakko". You should find some cheap soldering iron controllers around $10. I have used some of those with good results. Forget those that come with a (potentially unsafe) switched-mode power supplies in a metal enclosure costing around $30.

Use a good transformer with sufficient isolation for your own safety! Use a good transformer with low leakage current in order to minimize the leakage current as too high leakage current of the the cheap and poor quality switched-mode power supplies may destroy your sensitive components.

[shobo]

Start with something that is already done:

https://create.arduino.cc/projecthub/sfrwmaker/soldering-iron-controller-for-hakko-907-8c5866
http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=6302

Study how they work, build something, test. Develop your own. Or buy something simple and cheap from eBay and modify it for your own purposes. Go to eBay and enter "digital soldering iron controller hakko". You should find some cheap soldering iron controllers around $10. I have used some of those with good results. Forget those that come with a (potentially unsafe) switched-mode power supplies in a metal enclosure costing around $30.

Use a good transformer with sufficient isolation for your own safety! Use a good transformer with low leakage current in order to minimize the leakage current as too high leakage current of the the cheap and poor quality switched-mode power supplies may destroy your sensitive components.

The switchomode supply i have looks pretty good.i would like to use it since i already have it tho.

Some photos
https://drive.google.com/drive/folders/0B__3rkvfg_X0aHB2ZXFkaHNSZkE

[gildasd]

Be careful of those switchmode power supplies, even disconnected, they can injure or kill.
Learn before you start poking around, and if you poke, do it one handed with rubber soled shoes, so you'll just lose the tip of a finger instead of going into cardiac arrest.

[shobo]

Be careful of those switchmode power supplies, even disconnected, they can injure or kill.
Learn before you start poking around, and if you poke, do it one handed with rubber soled shoes, so you'll just lose the tip of a finger instead of going into cardiac arrest.

Well i'm not going to poke my fingers in it.Maybe a multimeter probe or something.either way i thing i'll take only the top cover off the power supply in the case.

[gildasd]

Even with a probe, be careful. Those big caps pack a punch.
I once vaporised the tip of a multimeter probe (2mm simply gone) following tracks on a supply that had been disconnected a couple of weeks...

[shobo]

Even with a probe, be careful. Those big caps pack a punch.
I once vaporised the tip of a multimeter probe (2mm simply gone) following tracks on a supply that had been disconnected a couple of weeks...

well shit son

[gildasd]

These things scare me and I've got a high tension certificate (6kV and above in kW systems).
I'm really not joking, I was following the ground plane in continuity mode, anud the caps discharged through the tip, more than enough energy to kill.

Edit; forgot to say that this finely pitted my safety glasses but did no damage to the board or the multimeter.

[Refrigerator]

Even with a probe, be careful. Those big caps pack a punch.
I once vaporised the tip of a multimeter probe (2mm simply gone) following tracks on a supply that had been disconnected a couple of weeks...

I bet it was a nice bang.
Once i had something like this happen to me too while i was measuring a live SMPS across the HV cap and forgot my probes in the 10A socket.
Needless to say the piece of wire that i had put across the fuse terminals turned into vapor and coated the inside case with copper.

@shobo
Make sure it doesn't overheat.
I bodged together a station with one of those two-buck hand pieces and it went over temp and melted the high temp plastic.

[shobo]

Even with a probe, be careful. Those big caps pack a punch.
I once vaporised the tip of a multimeter probe (2mm simply gone) following tracks on a supply that had been disconnected a couple of weeks...

I bet it was a nice bang.
Once i had something like this happen to me too while i was measuring a live SMPS across the HV cap and forgot my probes in the 10A socket.
Needless to say the piece of wire that i had put across the fuse terminals turned into vapor and coated the inside case with copper.

@shobo
Make sure it doesn't overheat.
I bodged together a station with one of those two-buck hand pieces and it went over temp and melted the high temp plastic.

I am still thinking about a method to calibrate it properly.Since the shape of the tip is fairly regular i was thinking to calculate the thermal characteristic of the tip,i.e. the heat transfer (i'm sorta a physicist).or maybe stick it into something hot a few times and extrapolate a curve or something. (by something hot i mean at least 3 different temps at least.)

[Refrigerator]

Before you go messing around with circuits you should find out the type and spec of the temp sensor in your heater.
If it's a k-type then it's about 40µV/^oC but if it's a thermistor then you need find the  /^oC. Only then can you start doing the schematic and PCB work.
And also forget the physics and thermal transfer for now. Just make sure your station at least works.

[Paul Price]

https://www.eevblog.com/forum/beginners/picking-a-soldering-station/msg840456/#msg840456

It is not that complicated to cheaply build your own soldering station with a bargain 888 handle and a few used parts to start with.

[Cliff Matthews]

Couldn't resist, this is worth a watch:

[buck converter]

Couldn't resist, this is worth a watch:

I was about to say...

[Cliff Matthews]

Don't think I've ever seen a YouTube Electronics video quickly go so viral. Comments and likes never end. Great to see!!  I wonder how JBtools will keep up stock levels...

[Kalvin]

Excellent project! With some modification the project is usable also with the Hakko T12 handles & tips.

Similar project but with more tips, more options and more complexity:

http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=7218&p=61175#p61175

[mariush]

It would be cheaper to buy the stuff from eBay.

for example, just search for "soldering station hand piece" , or add a brand in front "atten hand piece" "yihua hand piece" or handle etc ,and you'll get connector + cable + handle + heater element + cheap crap tip compatible with hakko tips for maybe 4-5$

ex  generic 50w 24v ac  (5 pin connector, probably 2 wires for 24v ac to the ceramic heater, 2 wires for temperature sensor, one for ground if you're lucky

1. ~ 5$ http://www.ebay.com/itm/W6-24V-50W-5-Pin-Female-Plug-Hand-Piece-Solder-Iron-Handle-for-Soldering-Station-/182355702588
2. ~5$ http://www.ebay.com/itm/24V-50W-5-Pin-Female-Plug-Hand-Piece-Solder-Iron-Handle-for-Soldering-Station-TS-/172375391098


5-Pin 907 Soldering Iron Handle For AT936b AT907 AT8586 ATTEN Soldering Station

1. 5$ http://www.ebay.com/itm/5-Pin-907-Soldering-Iron-Handle-For-AT936b-AT907-AT8586-ATTEN-Soldering-Station-/331725455824

atten 907 5 pin 60w 907 A1322 Heating Element 60W :

1. ~11$ (over 700 sold so it's probably good?) http://www.ebay.com/itm/New-Atten-Soldering-Solder-Station-Iron-Handle-for-907-A1322-Heating-Element-60W-/310998014151

 7-Pin 907 Soldering Iron Handle For AT936b AT907 AT8586 ATTEN Soldering Station  (this one has the atten logo onthe handle and everything, maybe it's sign it could be slighty more quality, may have extra wire for ESD safe feature, basically exterior metal of handle piece connected to earth through a resistor

1. 5.5$ : http://www.ebay.com/itm/7-Pin-907-Soldering-Iron-Handle-For-AT936b-AT907-AT8586-ATTEN-Soldering-Station-/221921974323


you can also buy Hakko 936 clone circuit boards for much cheaper than the cost of a pcb and components and everything
You have to pay attention to match the board you buy with the cable you buy (the heater element, usually the heater code is in the title , for example A1321)
There's also  model A and model B  where A is the one with female connector for the hand piece, and B is the one with male connector, usually.

 here's some examples:

8$ : HAKKO 936 Soldering Iron Station Controller DIY for 907 Iron A1321 Heating Core : http://www.ebay.com/itm/HAKKO-936-Soldering-Iron-Station-Controller-DIY-for-907-Iron-A1321-Heating-Core-/181794950587

5 uk pounds model A :: Controller + Panel Board for HAKKO 936 Soldering Iron Station 907 A1321 Core A : http://www.ebay.com/itm/Controller-Panel-Board-for-HAKKO-936-Soldering-Iron-Station-907-A1321-Core-A-/281907917810?
8.3$ model B :: Controller + Board Panel for HAKKO 936 Soldering Iron Station 907 A1321 Core B : http://www.ebay.com/itm/Controller-Board-Panel-for-HAKKO-936-Soldering-Iron-Station-907-A1321-Core-B-/252517250966?
10 australian dollars  male connector :: HAKKO 936 Soldering Iron Station Controller DIY for 907 A1321 Heating Core  ::  http://www.ebay.com/itm/New-HAKKO-936-Soldering-Iron-Station-Controller-DIY-for-907-A1321-Heating-Core-/172046689274

So you basically only have to get a 24v AC transformer ideally rated for 60VA or more and a box and you have a soldering station.

[pyroesp]

Couldn't resist, this is worth a watch:

Marco Reps made a nice DIY soldering iron video too a few months ago.

[Shock]

It would be cheaper to buy the stuff from eBay.

Hakko 936 clones are a bit yesterday. You can now get SMPS powered Chinese bastardized Hakko FX 951 based clones that uses T12 tips for $22 USD.

They also do kitset controllers, cases and power supplies. The fake T12 tips are more expensive than the 936 or T18 tips so it will be higher running costs but if you get a genuine Hakko T12/T15 tip running on one that would make for a nice station.

This specific one is branded Bakon, the case sucks but that could be easily cheaply resolved.

https://www.aliexpress.com/item/EU-Plug-Bakon-Digital-Soldering-Station-Portable-Soldering-Iron-BGA-Solder-Station-220V-75W-T12-solder/32798279428.html