Suggestions to level a background subframe

CWPS

Member
Joined
May 5, 2015
Location
Denver, CO
I've setup a truss frame from which I'll hang all kinds of backdrops. The frame is 20' wide and suspended from a parent frame with 2 hoists. Without using 4 hoists for a 4-point lift its challenging to level the subframe. The attached photo may help to explain.

My current idea is to attach the hook to a device that attaches to the subframe. The device would contain a threaded rod with a crank-handle that when wound moves the center point of equilibrium of the frame so that it becomes level. Hope that makes sense.

I'd greatly appreciate any suggestions.
Thank you.
 

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porkchop

Well-Known Member
Joined
Feb 19, 2008
Location
Vegas
First off I STRONGLY suggest you change your rigging so that the truss cannot slide around inside the spanset. That's not very safe, and the weight of a backdrop could cause a sudden, dangerous, and unexpected shift in weight. Two shorter spansets choked to the truss coming up into a shackle attached to the hook is the first solution that comes to mind.
Once you have the truss hanging in a more solid manor. To control the trim of one side of the truss you could use deck chain and turnbuckles to give you a pretty wide range of adjustment. One on each corner could control the tilt and more in between lift points could compensate for truss deflection if necessary.
 

CWPS

Member
Joined
May 5, 2015
Location
Denver, CO
Thank you for the suggestions. I've just learned what a spanset is why it's very important to change what I'd done before attaching anything. I've order some parts to do that.

If I understand your suggestion to trim the subframe, I'd need to attach it to the parent frame after the subframe is raised and then wind the turnbuckles. Is that what you meant?