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I am looking at building an offset head still and this brought up a question for me. In Ian Smileys book , he suggests using 1 1/4 pipe . I was wondering if there would be any advantage to making the column out of 1 1/2 or 2 inch and keeping the head at 1 1/4 . Wouldnt the increase in column size give you more plates , and therefore a purer alcohol , but the smaller head concentrate the vapors on the condensor more? Or should I just quit thinking and build as specified? thanks for any input.