Easy Heating

I built this simple cockpit heat box for my 601HD. After looking around

on the net for plans and not finding any (state secret? :) I decided to

design my own. I'm very happy with the results. The inlet is 2" and the

hole in the firewall is only 2" as well. Arm is actuated via a

push-pull cable purchased at a local automotive store (Canadian Tire).

Box is made with .025" T6 sheet taken from trimming scraps and a simple

hinge purchased at the same store. 1/16" cork is used as the gasket

material. The overall size is 4.25" long for the box with a 1/2" tabs

on either end for mounting and the width is 3". One of the triangles is

a bit longer to accommodate the flapper movement (longer one is the top

with the inlet flange).