Cheap Hot Air Station With Arduino





Introduction: Cheap Hot Air Station With Arduino

first , it's my first instructable and i'm not native in english so be gentle

I had an idea weeks ago , build a hot air station for cheap , very cheap , i don't need a big stuff just a little station for few soldering.

i've find on ebay the 858 hot air station but to expensive for me, so i just buy the handle for 8 euros! and i have built a circuit with a arduino to control this handle.

lets go!

Step 1: Study the Handle !

The handle comes with 8 pins:

2 wires for the heater , it works with 220v ac ( i dont know for 110v) it is the grey and the white wire.

2 wires for the 24v dc fan plus is blue ans gnd is brown

1 wire for the reed switch the green

1 wire for the earth the yellow

2 wire for the thermocouple red (plus ) and black

now how to control this?

i will separate in section the rest of the project

first the heating

Step 2: The Heating Control

the objectif is realy simple : start and stop the heating with a logic command of 5v .

But we can't do that with 220 vac easily the solution : a triac and an optocoupler,

tric is like a relay but static , it is control by an optocoupler to secure the rest of the circuit.

it is done here with a moc3063 and BTA140-800

Step 3: The Fan Control

the fan works with a 24vdc, it must be activated always when the gun is hot .

we have two commands: the first is to power on the fan with the arduino it's a simple transistor . the second is a potentiometer to control the speed .

note: here the components are not the best, i take what a had in stock and it works great!

Step 4: The Arduino

the arduino nano control all the things,

to measure the temperature i used a module with a max 6675 connect directly to the thermocoupler of the handle,

the max6675 is connect by spi to the arduino and the supply library is very simple to use.

I put 2 push buttons to control the temperature and a lcd , the lcd is control by i2C it's overkill but i only had this in stock so i used it!

there is a led wich is lighting when the heater is on

to conclude the arduino is connect to my card build earlier.

Step 5: The Code:

My code is the simplest possible:

first: i don't implement for the moment the reed use when you put-on the station the gun is always on!

then we read the temperature if it is lower than the consigne the heater is put on , and stop when it reach the goal !

with the two button you adjust the temperature.

that's all.

Off course it's not perfect but i thought it would be a good starting point for all the beginner in electronic.

Step 6: The Final

what's next?

in the future i would like to add the reed switch support , ( i've ordered in china the handle support) and most important the pid for the temperature management,

if you'd like to implement fonctions please be free and contact me , i will be very happy to test it!

3 People Made This Project!


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For the bracket :

En ligne 45 le remplacement de lcd.init() par lcd.begin() résout le blocage pour ma configuration. Tout fonctionne.


Des pb liés je pense à la bibliothèque LiquidCrystal I2C la ligne 45 est rejetée...


des soucis avec la librairie Arduino LiquidCrystalI2C et MAX6675, une aide si c'est possible, il ne me reste plus que la prog du Nano à faire.


Hello. I really like the project, thank you.

I want to build, but I think I would like to see the reed switch and PID support; have you managed to try this yet?

Thanks, well done

hello sir my max6675 read very strange value like 300 , 600 & 700 while heater on and only read correct if heater is off

ERRATA: HOT GUN ~US$18.00 => ~ R$60 (BRL)

Pretty good, neat instructable


Real nice project ! Some links to the place you ordered everything might be usefull, but anyways, I will probably build my own :)