The basic idea is to transfer the added weight of the gourds and their contents to the heavy steel plate that supports the house, rather than to the light aluminum house itself. I used a 4-foot long 5/8" diameter dowel to hang 2 gourds from and as a perch rod. I used 1-1/2" #10 machine screws in 2 of the plate's 4 holes (One or both selected holes already had screws in them). The holes were selected so as to allow the dowel to clear the hole for the post and to emerge from under the house at its sides.
The dowel has clearance holes for the screws drilled in it, located so that the dowel projects approximately an equal distance on each side of the house. Temporarily putting the dowel on the two screws, 2 clearance holes are located for attaching a gourd just outboard of each side of the house. A lockwasher, nut, and 3/8" spacer are run up each screw before the dowel is attached with a flat washer, lockwasher, and nut on each screw. The spacers are used so that the dowel clears the bottom of the house's lips.
This method could be expanded to add another dowel and pair of gourds, but I find the weight of full occupancy of the house and 2 gourds hard enough to pull up with the rope and pulley system. I treated the drilled out dowel with some DAP Woodlife wood preservative that I had on hand. I have 3 old TG-12s modified this way, and have not had a dowel failure in 2 years. The diameter of 5/8" was selected as the result of a study of the optimum diameter for a perch rod. A larger diameter wooden dowel or a stronger material could be used.
Tony Berg
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