Here's the one I built from TIP plans in about 1987, from furniture-grade particle board. I've been using it every day in my business for the last 17 years. The back panel right in front of the operator position has eroded maybe 1/4" deep in a few spots, so I will probably install an overlay maybe 18" x 36" on the back wall.
I made it 48" wide instead of 36" per the TIP plans. TIP has you throw away the 1' strips, and I couldn't see wasting the material and not having the larger cabinet. I had to re-calculate the walls of the funnel, but that was no big deal.
I wouldn't be without this tool.
Joe
