Larry_Loo

I do not recall exactly how the outside grills for the side-mounted air conditioners are attached to the trailers. I assume that the grills are attached by screws - e.g. sheet metal screws - to the outside panel of the trailer. One permanent solution would be to remove the grill and attach anchor nuts (or nut plates, in aircraft parlance) to the outside panel around the margin of the rectangular or square opening. You can purchase "floating" anchor nuts with 2 holes on opposite sides of the nut (the nut floats within a small sheet metal housing). These anchor nuts come in sizes such as 6-32, 8-32, 10-32 and larger. A hole moderately larger than the diameter of the screw being used is drilled where you wish to fasten a screw to the panel. An anchor nut is centered on this hole and 2 outboard holes are drilled for the pop rivets. The floating nut compensates for any slight misalignment of the screw holes, or, even slight angulation of one part against the other. Then you can fabricate a lightweight panel of thin plywood, masonite, or aluminum with attachment holes to match the pattern of the anchor nuts. If the grill protrudes out slightly beyond the surface of the outside panel - as many do -you will have to fabricate a flange or built-up edges so that you have a dish-like cover. If you know someone who has access to a sheet metal brake, you can make an aluminum cover that will look very professional. When sanded smooth and painted with enamel paint, however, even a plywood cover can look like a factory-made one.

The anchor nuts are available at some well-stocked hardware stores and at all aircraft supply houses - such as Aircraft Spruce, Corona, CA (800) 824-1930 or Griffin, GA (800)831-2949. If you can't find them in your local hardware stores and would like to see what anchor nuts look like, send me a self-addressed envelope and I will send you a copy of a catalog's page that shows them. Anchor nuts cost from $.18 to $.50 each for the smaller sizes. My address is P.O. Box 395, Clovis, CA 93613-0395. ;D