Don't know if this has been done before, but if it has I haven't seen it. Mimosatexas started the wheels turning in my head when he mentioned using wood to widen a sheet pan rack, so credit to him for that. Once I had the racks with the intention of going that route, my printer came up with this idea. It's worked out great for us and is pretty easy to do so I figured I'd share.
1. Find cheap sheet pan racks (bakers racks, speed racks) on Craigslist. I found a guy selling a bunch for $30 each fairly easily. They're out there if you look.
2. Take racks apart, keeping only the two sides.
3. Pull some of those old, beat to death statics out of storage.
4. There are usually three support levels on a standard speed rack. Top, bottom and middle. Line up the side of a static with the existing holes on the rack and drill completely through. Repeat for all levels on both sides, using three screens.
5. Get yourself some 3" bolts and nuts, 12 per rack. Also pick up a bunch of washers.
6. Run the bolts through the outside of the rack, and use 4-5 of the washers between the inside of the rack and the frame. This adds a little space making it easier when sliding your screens in and out. Repeat. With a little creative placement, you can retain every space on the rack for use. A 23x31 setup will also hold 20x24 by angling the screens a bit.
7. Enjoy your new screen racks. My cost for three was under $40/ea.
Pics attached.