I wasnt happy with the time it took to place each component just right, so everything would line up perfectly, then tear it down at the end of the run, and have to reposition everything again next time. I also didnt like the size of the footprint required, and number of parts I would have to transport, should I want to use my setup elsewhere.
This is what I came up with (photos below).
I cut off the top section of 2 50Ltr kegs (depressurized, with the valve stems removed). I also cut the handle banding off of 1 (this will be the bottom section).
I had a 2" triclover cap with a 1" threaded hole welded to the inside of the "bottom" section. To this, I threaded in a copper section (see photos) then the top section welded on. (My welder purged the tank with some fancy stuff to prevent and sugaring in the tank).
This is now my thumper.
It tri-clove clamps to the top of a 50Ltr keg, which I cut most of the banding from, leaving only the handles. This allows space to attach the tri-clover.
The stack/lyne arm/liebig are all 1 piece. 1" pipe reduced to 1/2" into the liebig with a 3/4" jacket.
I had to add some 1/2" pip and a 90 to the inlet of the liebig to prevent kinking of the hose, and provide clearance of the keg pot and the propane burner.
And finally, I attached a skull to the end of the liebig to make it that much cooler.
I call it ASTRO-21
