support for large frames

[bratton]

What do you do with large (4'x7') frames for extra support and to prevent them from warping when adding plex and heavy artwork to the package?

 

[RoboFramer]

Hopefully have a blockbuster of a frame to start with that won't warp no matter what you bung in it.

But regardless, corner braces and a sturdy backing board, possibly with crossmembers

 

[bratton]

What do you use for the crossmembers?

 

[McPhoto]

Aluminum straping would give support w/o added weight

 

[David Waldmann]

A "strainer frame" that goes in the back is a fairly traditional way to strengthen a proportionally large frame. We make strainer bar material as large as 3/4 x 2-1/2 (on a custom, per order, basis) for several customers that regularly work with very large frames. For frames of the dimension you mention (and much larger) in addition to the perimeter frame, a grid-work is also added to provide necessary support. Some people use welded aluminum, but that takes equipment most shops don't have.