A few months ago, a friend of mine constructed a Liebig cooler from copper tubing. Unfortunately for him he didn't have the equipment to test it. Fortunately for me I did have the equipment to test it and boy did it work well. The only complaint was that it was difficult to get this piece of equipment correctly set up because there was no legs or brackets for it.
I decided that it was time for me to build my own and I came up with the idea to integrate legs for the cooler into the cooling part of the system. The advantages were that it is easy to set up and there is no rubber pipes hanging around to trip over.
First photo: Liebig condenser/cooler with integrated feet.
Second photo: My friends Liebig condenser/cooler.
What is a Liebig cooler?
A Liebig cooler is a condenser used to produce essential oils and alcohol. It basically cools down alcohol vapours and condense it to form an alcohol liquid. If you need more information about making alcohol (moonshine) please visit my website Beer to Spirits
Please be sensible when you construct this project. You will be working with metal and there will be filings that could end up in your eyes and hands and feet. You will also work with molten metals (solder) and if you don't concentrate on what you are doing, you will burn yourself. Wear appropriate safety gear for your eyes and hands and make sure the area is well ventilated when soldering. The fumes can be bad for you.
In some countries and states, it is illegal to make your own alcohol. Please check your local laws before getting into trouble for making moonshine at home.
Step 1: BOM (Bill of Materials)
The entire Liebig cooler is constructed from copper tubing available at your local plumber or hardware store. The list of materials are as follow:
- 3 X 1.5m 3/4" copper tubing
- 1 X 1.5m 1/2" copper tubing
- 2 X 3/4" to 1/2" reducers
- 2 X 3/4" by 3/4" by 1/2" T pieces
- 2 X 3/4" T pieces
- 2 X 3/4" caps
- Solder (I used normal 50% lead solder because none of the parts that touches the liquid was soldered)
- 1 X 1/2" compression fitting (optional, depends on how you connect your cooler to you boiler)
- Turpentine (optional, used to remove stickers from tubing)
- Steel wool or fine sand paper
- Salt (used to bend the tubing)
- Ducked tape (to plug the ends of the tubes
As you can see, there is not a lot of materials needed for this project. The tools I used were basic tools that most of us have, here is a list:
- Hack saw
- Round file
- Blow torch (in my case I used a gas soldering iron)
- Work bench
So lets get going.
Step 2: Bending the Inner Tube
The first thing I did was remove all the stickers and labels from the tubing with some turpentine. Now to bend copper is not that difficult but I took some precautions because I did not want to mess up my newly purchased tubing. I basically plugged one end of the 1/2" tubing with some ducked tape and filled it with salt. I then plugged the other end as well. Now before you start telling me that sand would have worked better, I must say that I am new to working with copper and I found that it is almost not necessary for the salt when working with thin copper tubing.
I used the entire 1.5m length and gave it a nice bend at the one side. (See picture) The bend came out real well and I was pleased with the result.
Step 3: Prepping the T Reducers
With the 3/4" by 3/4" by 1/2" T reducers, you need to prep them first before they slide over the 1/2" tubing. There is a little groove inside these reducers that causes them to not slide over the tubing. I used a round file to remove the groove inside but if you have some kind of rotary tool, I would recommend that you rather use that to romove this little groove.
To be completely honest, it took me way too long, more than an hour, to get this little groove removed simply because I did not have the correct tools. In any case, I eventually won the battle.
Step 4: Bend the 3/4
Your Liebig cooler must be at an angle to function properly. To achieve an angle on this build, I had to bend the 3/4" tubing as well. Boy, this was no easy task. Unlike the 1/2" the 3/4" tubing is much stronger and thicker. I must admit that I completely buggered up on piece of tubing when I did this.
I highly recommend that you use the salt here and also get someone, with some muscle :), to help you here.
Step 5: Cutting the Tubing
Now that you have all the pieces bend and the connectors prepared, it is time to cut your tubing to the correct length. I wanted a cooling section of at least one meter and it worked out well with the inside tube being 1.5m in length with the bend.
You can make your cooler as large or as small as you like but a general rule is that the cooling part should not be less than 750mm.
A few notes on cutting copper tubing. Make sure you do not distort the form of the tubing at the end. This will make it difficult to get the fittings pressed on. There are specialised cutters available to cut copper tubing but it is expensive and since I don't work with this everyday, I took care not to distort the ends.
Step 6: Prepping for Solder
This was my first time I actually soldered copper tubing. I did my homework first because for some reason a lot of people say it is hard to do this. Personally I did not find this hard at all. The most important thing that you must do before you try and solder copper tubing is the preparation.
Make sure the part you want to solder is clean! Make sure the part you want to solder is clean! That is not a typo, it is a very important instruction. I used steel wool to clean the ends of the tubing and I folded a piece of steel wool around a drill bit to clean the fittings on the inside.
Once you are done cleaning, assemble your work and start heating up the connection with the blow torch. Make sure that the piece is heated evenly and sufficiently. You will know it is hot enough once you push the solder against it and it simply flows right into all the gaps. You do not need a lot of solder and it will spread easily around into all the gaps if the temperature is correct.
Note that the solder I used had a flux core. If your solder does not have flux inside, you will need to use separate flux. The flux helps to bond the solder with the copper. As you can see from the pictures, my soldering is not the best in the world but it was good enough.
Step 7: Test for Leaks and Conclusion
After soldering, you can test your work piece for leaks. I connected a small fountain pump and 13mm clear tubing to the cooler and pumped a few litres of water through it. All the joints was perfect with no leaks.
To make the cooler look a bit nicer, I cleaned the whole piece with steel wool and removed the unwanted solder from it. You can cover it with a clear lacquer if you want to prevent it from going dull.
I hope you enjoyed this instructable and enjoy the use of it.
Step 8: Update
Here is a few photos of the Liebig condenser in action. As you can see, it is a small set-up and I can only distil about 5 litres of wash at a time.
In the video you can see the drip-rate or in this case flow-rate of 65% ethanol being distilled to about 82% strength. In the last picture you can see the strength of the distillate.
Happy brewing and don't drink 82% pure vodka, it will most probably kill you!!!