Evergreen Tubing Info
These fittings are made to use Evergreen tubing to create ductwork. There is no scale as such – you simply need to select the size tubing that will best represent the ducting you are modeling in your scale.
Note: The sizes shown for the tubing is ‘nominal’. While this does not matter for the OD, it does for the ID. The tubing I believe is produced much like a pasta extruder ,, through a die so the ID can vary by a few thousands of an inch. If the fitting does not slide easily into the tube you will need to either use an emery board to swipe the end of the fitting or use an appropriate size drill bit to ream out the round tube to make the fitting fit. Mostly this is not needed and the fitting will fit to the tube easily.