yup.. a cheap (new. not one that's been used for soldering already) soldering iron... I used a big soup can.. drilled a hole in the side at the bottom for the tip of the iron to go in.. filled with chips... put a cover of aluminum foil, with holes poked in it, over the top (this seem to make them last longer)... I used a big cardboard box set down over the top of stackable racks and the cold smoker... put a vent in the box at bottom on one side and top of the other side.... worked great for cold smoking (cheese, eggs, etc.).... I still have the set up too...
That's the only way I know of to be able to use chips for cold smoking...