Introduction: Einhell XChange - Soldering Iron

I always wanted a transportable soldering station. After a cheap gas-soldering iron caught fire, I was looking for soldering stations with a rechargeable battery. The ones I found weren’t that cheap or didn’t fit my needs, so it was time to design one by myself.


This project includes:

  • 3D-printed parts
  • Laser-cut metal parts
  • Hot glue
  • Sensor cable 4x0,34 mm² (approx. 1 m)
  • Flat male crimp contacts 4,8 mm (2 pieces)
  • DC soldering iron (can be found on Aliexpress)
  • DC Jack connector
  • M3 nuts and bolts

Step 1: The Einhell XChange System

Due to the reason that I already had an Einhell jigsaw I wanted to design a soldering station that fits on the Einhell xChange system.

The fact that Einhell offers a lot of tools on the cheaper side for their xChange battery-packs supported my decision, because I suspected that the whole intelligence must be in the battery-pack to produce the corresponding tools cheaply.

To prove my suspicion, I opened the jigsaw and found a very basic electrical circuit.
Everything was directly connected to the battery.
The “switch-unit”, which also regulates the motor speed, needs a MOSFET for operation, but that shouldn’t be something to think of, when designing the soldering station.

Step 2: Assumptions

The battery-pack has a rating of 18 V and 3 Ah, which equals a total energy of 54 Wh.

If a 65 W soldering iron would be used, it could run for about 50 minutes at 100 % power (which is not totally correct, but in this case, the calculation fits the needs).

A 65 W soldering iron draws a current of 3,6 A at 18 V.

Step 3: The Electrical Design

The electrical design is quite trivial, because the whole brain is in the battery-pack and a soldering iron which works from 12-24 VDC is used.

Step 4: The Mechanical Design

Due to the reason, the station should be transportable, the design had to be as compact as it could be.
Also, the 3D-printed components should be reduced to an absolute minimum. I decided to design and print a top and bottom part. Between the 3D-printed parts there’s space for a PCB.
And aluminum-holder was designed and laser-cutted for the soldering iron.

Step 5: Assembly

For the electrical connection I hotglued crimp connectors into the adapter, which works really good.
I decided to use an industrial sensor cable (4x0,34 mm²) for the connection to the soldering iron, because it is thin and very durable.

Step 6: Final Thing

After two hours of assembling the soldering station turned out pretty fine, I think.
Also attached are the assembly STL-files.