Got my flask cold smoker going
all i did was remove the plastic from a large stainless vacuum flask including inside the cup, drill a few holes in the bottom of the flask, through both layers , drill and attach a 15mm tank connector to the cup/lid and one in the side of your barb/trashcan or dustbin over here, connect with a piece of 15mm copper pipe ,and use compression fittings as its easier to get the wood going on the stove, as for air i use my pond air pump ,only a pond air 2 to a ttin which had salmon in it"the small one" just drill a hole in the side and use silicon tubing from the acqurist shop "pond place"
through a tight hole near the bottom.All you have to do is sit the flask on top. As for fittings its up to you i used conex as its easier to dismantle and heat the wood up on the stove for me, puipe lenth and diameter , i think 15mm is ok but some use 22mm ,but you may have other options
A reguating valve and one way value would be useful from you pond place, but regulating the airflow depends on your pump.
Gaz