Liebig Condenser

Introduction: Liebig Condenser

A Liebig condenser uses a coaxial two pipe system where the outer pipe (water jacket) circulates water to pull heat from the inner vapor pipe, condensing the vapor inside it into a liquid.

This type is approx 4 feet long with a 1" water jacket (outer) and 3/4" vapor path (inner)

With appropriate water flow, this condenser can knock down vapor for any still under 30 Gal and probably even larger.

Taking up this or a similar project you put yourself at risk and I take no responsibility for any injury/damage or unlawful use of this knowledge, this guide is for educational purposes only.

This project involves, high heat, molten metal, metal dust, and fumes. Perform in a well ventilated area, preferably outside.

Word of real warning, My soldering is on par with a monkey, be warned!

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Step 1: Tools & Gear

You'll need...

Propane or MAP torch, Flux (water based), Lead free plumbing solder (not acid or rosin core)

Gloves, safety glasses, respirator

Sand paper (coarse)

Dremmel with both grinding/sanding and milling attachments (can be substituted with sand paper, but requires A LOT more effort and time)

Metal Vice

Pipe cutter (1/8-1")


Power Drill with wire brush (for cleaning up the pipe and smoothing solder)

Angle Grinder with cut off and grinding disks (can replace pipe cutter if needed)

Step 2: Materials Needed

All pieces are copper to better conduct heat, maintain sterility and help fight sulfur in distillate.

Pieces needed

(2) 1" X 3/4" X 3/4" Copper Tee

(1) 1" Copper pipe (4 feet long)

(1) 3/4" Copper pipe (5+ feet long)


The following pieces are for optionally adding an easy means of connecting feed and waste water hose

(2) 2" long sections of 3/4" Copper pipe

(2) 3/4" Brass slip on nozzled fittings (can't remember the accurate name, second picture)

The following is for adding additional water turbulence, elongated flow, and more even cooling

(1) 5' Long 16Gauge solid Copper wire

I purchased 8 Gauge by mistake and it wouldn't fit, so I just show how to add it, but proceed without it.

Step 3: Optional

Gradually wrap your Copper wire around the Vapor Tube, 6 inches from the top and 6 inches from the bottom.

You want to maintain a consistent spiral to keep the water moving evenly without speeding up or slowing down.

You can either secure this by soldering the end points and some intermittent sections, or use a mechanical fit between the vapor pipe and water jacket.

Step 4: Adding the Tees

As seen in the first picture there is a little ridge/stop inside the Tee to stop the 3/4" pipe from going too far inside.

We need to mill/grind/smooth this down so that our 3/4" pipe can snugly pass through the Tee and out the 1" side.

It's important not to remove too much material and remove material evenly. Intermittently remove material, smooth, and check if your pipe will fit through.

The milling tool on the dremmel is a quick way to remove material here. Try to conventionally mill (move in the direction the mill spins) rather than Climb mill (move the bit in the direction opposite of spin). Then sand down what's left.

You can also sand the ridge down from the start, this just takes longer.

When you are finished, do the same to the other Tee.

Step 5: Soldering; Adding the First Tee and the Water Jacket

This step will explain how to solder, the following steps will not as it is all the same. If you have never soldered pipe before I suggest practicing beforehand and watching some youtube videos. {link to many vids}

1) Prep for soldering by sanding the inside of the 1" and top 3/4" connection of one Tee. Also sand the top end of your 1" pipe and about 6 inches down on your 3/4" pipe so that it lines up with the 3/4" top mouth of the Tee. *Sanding provides a rough surface for solder to hold on to.

2) Apply a generous amount of flux to all sanded areas prepped in step 1

3) Slide the 1" mouth of the Tee all the way down into the prepped side of the 1" pipe

4) Put 1" pipe section in vice, DO NOT hold the pipe even with gloves. It's too hot and you'll need both hands anyways.

5) Unwind about 10" of solder wire, put on your safety glasses and gloves, open the torch valve and ignite the flame

6) Heat the joint with your torch

7) Once the flux looks like it has melted away and fumes are coming out the end of the pipe, apply a line of solder to the joint, the solder should melt then quickly lay flat at the joint, this means you are at a high enough temperature and the flux is "sucking" the solder into your joint. If not, then keep heating and try again.

8) keep applying heat and solder the entire 360 degree joint

9) let the section cool, it is very hot even if it doesn't look it

Now once the Tee and 1" pipe cools to the touch slide the 1" pipe and Tee over the 3/4" pipe so that the outer 1" pipe is in the center of the 3/4" pipe. The flux from the 3/4" top Tee opening will smear but that's fine, just apply more around the joint and then solder held in a vice as similar to above. you should end up with the third picture of this step.

Step 6: Cap Off the Water Jacket!

Now similar to the previous step, sand and flux the needed connections on the second Tee and the other ends of the pipes. Slide the Tee down and start by soldering the 1" pipe to it. Reapply flux to the 3/4" connection as some of it will melt away during the soldering of the 1" side, then finish the job and solder the last connection!

Step 7: OPTIONAL: Adding Easy Water Hose Connection

Sand the inside of your Brass fittings, both ends of your 1-2" long 3/4" copper coupler pieces and the inside of the last open 3/4" hole of your Tee. Apply flux, and solder in any order so that they are all attached.

I soldered the coupler to the Brass fitting and then soldered the two conjoined pieces to the 3/4" Tee hole.

Step 8: Finished!

let'r cool down and you're ready to hook up your hoses, pump, etc!

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    3 Discussions


    7 weeks ago

    Nice tutorial. I especially like the hose nipples that you soldered on as many homemade condensers I see have sketchy hose attachment. Thank you for sharing this.


    3 years ago

    Great documentation!


    Reply 3 years ago

    Thank you! It was hard to remember to take pictures at times.