Strap on the backpack harness, turn on the air compressor, grip the handles, and slowly walk backward--this is all that is required to operate this aluminum vibratory screed. One worker who actually wears the screed can position and maneuver it.
The screed consists of four basic parts: the vibratory screed beam, the counterbalance frame, the backpack harness, and a counterweight. The weight of the screed beam is counterbalanced by counterweights added to the end of the frame, behind the operator. This makes it easy for the operator to maneuver the screed, especially when he needs to lift it up to get around pipes or conduit sticking up through the concrete.
The screed beams are equipped with pneumatic vibrators. The longer the screed beam, the more vibrators that are needed. The standard 6-foot beam has one vibrator; the 9- and 11-foot beams each have two; the 13-, 15- and 17-foot beams each have three vibrators; the 19-foot beam has four; and the 21-foot beam has six.
If screed rails or side forms are used, even an unskilled laborer can operate the screed. All he has to do is walk backward slowly, making sure the screed beam rides on the screed rails.