Very neat little motors can be found in scrap CD/DVD Players. They are 5 volt DC, reveresable. Can be run from 1.5v to 5 volt DC.Gearing will of course be required, either by belt or gears. They are very quiet running. Use a 2 /1/2" Perforated Strip, which will require 2 x 2mm holes to mount the motors. See Photo. The can also be mounted on Part Nos. 48 or 48a. Use the original Screws. The holes can be drilled or punched. This is rather fiddly, but gets easier the more you do. Friends always give me their old electrical items!