you don't need a lathe , the generic classic bat and the 901 atomizer are the same diameter ( 9.35mm) so the battery can be used for the adaptor.
keep the thread in the battery, remove everyting else in there, cut to deired length ( probably around 12mm long ) remove female thread from 901 atomizer. solder a wire to connect the centre poles of the male and female threads , insulate it, push the 901 atomizer threaded connector into the cut down battery housing.
Job done.
I shall try it in the week.
get to it dude.. just bear in mind its not how we would or could do it.. somehow structural strength has to be added if u dont want it to fall apart the first time any sidewards load is applied to it.. breaking it "unbreakable" is one reason we aint keen on offering one to the public..
returns is one thing we are trying hard to avoid..
trog