Two "Y" tubes are being used to provide for cabin heat/vent and defrost circuits. I am adding rotating doors to the "Y" tubes to allow for turning the defroster circuit on or off. The initial design and door for the first "Y" tube took a bit of time. The doors are made from brass rod for the pivot, square brass tubing for the connection to the mechanism, thick walled aluminum for a bushing surface and custom laser-cut plywood door parts. The brass parts were soldered for assembly, the aluminum was glued with T-88 epoxy and the the wood parts were glued and finished with the epoxy. The end result weighs little and is very strong.
