By Dave
February 24, 2020
Tig Welding Copper Moonshine Still
When it comes to building a copper moonshine still you will inevitably need to join two pieces of copper pipe together. There are many ways to do this including brazing and soldering, however I have found Tig welding to be the best, especially for large copper pipe joints where a lot of heat is needed due to the copper becoming a heat soak.
Torch Setup
The 2 inch copper pipe used in this example is 1.22mm (18g) thick so the tig torch setup I went for was a series 17 torch fitted with a number 12 Pyrex cup and a stubby gas lens. The tungsten used for this example was a 1.6mm thoriated tungsten. This was chosen as the thoriated tungsten is the best suited to copper tig welding. I used 60 amps to perform this weld which may seem a little high if you aren't familiar with copper tig welding. This high amp setting is necessary because the copper dissipate a lot of heat away from the weld puddle therefore you need more heat to maintain the puddle.
Weld Type
The two pieces of copper I'm welding together here fit really tight so I chose to fusion weld them together. Fusion welding is where you only melt the parent metal together without adding any filler rod material.
Step 1
The first step in the process is to clean the copper pipe really well. I like to use the Green Scotch Brite for this step.
Step 2
The next step is to "tack" weld the pipes together in a number of spots. This will prevent the pipes from moving during the welding process.
Step 3
Once the tack welding is complete it's just a matter of running around the join with the torch to fuse the two pipes together. Then with a little polishing you are left with a very clean looking join.
