While 100-foot-plus wide screens are impressive, big sizes can
mean big headaches.
The award-winning StageScreen modular screen was designed to
be among the strongest truss-style screens on the market. Though the 8” truss-style
product is very strong vertically, it is less strong in the horizontal plane
due to its I-Beam construction. So when it is lifted off the ground from fly
points, the frame will arch until it is vertical.
There are a couple of ways to minimize the arching when
raising a flown screen from the ground. Adding doubled-up “stiffener bars”
across the top will provide additional support to the joints and give an added
safety factor once the screen is in position. This is especially necessary when
fly points (where fly cables attach to the screen frame) are spaced 12’-18’
apart. We don’t recommend fly points be further than 18’ apart on the
Frame pieces should be wrench-tightened if possible, but stiffener
bars should only be hand tightened. Once the screen is vertical, some frame
pieces may bow forward or backward. You can push on the joint in the opposite
direction of the bow and hand tighten the stiffener bars at the same time to
take out the bow.
Another tip is to build the frame in the vertical position,
instead of building it on the floor then hoisting it vertical. If lift points
drop all the way to the floor, the upper horizontal frame can be attached at
shoulder height and fabric can be attached along the top of the frame. By raising
the screen a little bit at a time, installers can build the frame sides and
hook the viewing surface as the screen is lifted into the air. The only
potential problem to watch for with this method is someone stepping on the
viewing surface and leaving a big, dirty boot print. This approach is faster and
eliminates the arch in lifting. It’s also a real knee-saver for installers!
For more tips or technical questions about Draper’s
StageScreen, contact your Draper representative.
For more information on the StageScreen, click here. (http://www.draperinc.com/go/StageScreen.htm)
Source: Blog Posts