Heavy-Duty Control Horn System

Model Airplane News, Jul 2003 by Bell, Rick

Giant-scale models demand heavy-duty hardware, and one of the most important areas is the control system. With today's high-performance models, the control system must be up to the task. Enter Du-Bro Products' Heavy-Duty Control Horn System. Designed for big planes, each pack contains components to hook up two control surfaces, such as the ailerons or dual elevators. Included in the package are two each of the following: molded clevises for threaded 4-40 pushrods, 8-32x2-inch socket-head bolts, precision-machined aluminum pins, adjustable control horns, aluminum supports, molded washers and a bunch of steel cotter pins. The control horns are 1 5/32 inches long, and that makes them very versatile. If used on the ailerons, they can be installed so that the horn pivot point is in front of or behind the hinge line for differential throw. For normal installation, if the arm is too long, it's a simple matter to drill a new hole for the pivot pin where needed and cut off the excess arm length.

The system is super-simple to mount; you need only drill a 5/32-inch-diameter hole in the control surface for the 8-32 bolt. The bolt is then inserted into the molded washer and through the drilled hole. The washer has a recess for the bolt's head and a broad base for plenty of support. The aluminum support is then threaded onto the bolt, and it clamps (or locks) the control surface between them. Next, the control horn is threaded onto the bolt, and the clevis is attached to it with the steel pin. The linkages are then attached and adjusted for neutral. When set, the cotter pin is installed in the pin, and the legs are bent over to secure it. The procedure takes about 10 minutes.

Du-Bro has a winner on its hands with this Heavy-Duty Control Horn System. The parts are easy to install, easy to adjust and, at only $7.95 for a set of two, easy to afford. Why not give them a try on your next giant-scale project? I'm glad I did.