Started with 2inch copper tube and have 15ml tubes to go inside. Decided on four tubes to enable adequate cooling water to circulate around. My 2inch tube was a meter long(that's how they sell it, by the meter) and my inner tubes are 700ml. There will be reducer caps each end. Soldering is a bitch and at the end of my sunday afternoons effort I have still got some leaks going on so stopped and will let my mind clear b4 giving it another go...my work so far
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