I found this thread on accident, and was planning on building the exact same thing. I've made a flashlight mod but was disappointed in the aluminum and lousy threading on a cheap flashlight. I have a $20 flashlight that will fit and flat head 18650, but that defeats the point of making a cheap mod. I found myself looking at 3/4" ID M copper pipe in HomeDepot, it looked perfect. I didn't think my idea was going to be original, as
vaping has been around for years and I just got off cigalikes last January.
I haven't thought of a safe, reliable way to make a mechanical switch yet, so I'll be using C&K switches for the first one or two copper pipe mods. I picked up a Zmax control board for a third pipe mod, and once I find a good switch/button cover and window I'll tackle that job. I have some Lexan for the window, and a trimmed ink pen clicker might work for the button but I'm more interested in making a semi-mechanical mod first. I would like to remove the red ink stamp that runs down the side of the pipe, and that will leave the copper unprotected from the acids of the environment. I'm not sure how quickly sweat, oils, and
e-liquid will patina the copper, but I've read that wax paste like Johnson's is good for basic protection. I'll probably try some torching on the second one, I really like the iridescent look.
I ran across a couple of videos on you tube when making the most obvious search, "copper pipe mod". One of them seems like a bad idea, the other has a great solution to end cap "threading". I really like this thread and I hope these videos will provide as much inspiration to the rest of you as they did for me.
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