Originally Posted by SystemTech
Well my pot is a mixture of copper and aluminum and trust me, there is not leakage from the seam nor will there ever be. The way to put them together though is to heat them and then use a 2ton (or greater) press and then when it cools, its on there forever. Besides, there is really no corrosion at all. i bought my pot second hand (know the maker) and in total its probably about 2-3 years old and not 1 tiny hint of corrosion.
That was the idea that I had. I planned to use a 4.5" diameter billet 7.25" long, throw it on my lathe and machine a step .375" high, and 3" in diameter. Then machining a 1.375" hole with a depth of .600". Flip it and machine the inside to a diameter of 4.30" at a depth of 6.750. From there I had thought about a few other ways of making the insert. Either making it as a "plug" that could simply be pressed in from the bottom, or making it it to fit inside the pot, with a piece that would fit inside the hole on the bottom. Pretty much a tray inside of it.
I guess as long as it was fitted tightly there wouldn't be any room for moister to get trapped between the two metals. Hopefully that would allow me to get it dry enough after every run to make sure it wasn't going to corrode. From my experience, placing two metals together isn't much of a good idea. Something between copper and aluminum causes this kind of odd "blow out" effect when the copper begins to corrode.
Another idea was making the two pieces, and then poly coating the inside to keep moisture off the metal, but I'm not sure how that would affect the temperatures.