Hot answers tagged do-it-yourself
From the discussion about protecting board sufaces comes the idea of placing a sheet of Plexiglas on top of your board. That just might have enough weight to push it down. If it doesn't you'll still have a flat albeit slightly tilted surface.
I was poking around the other day looking for the same answer. Plaincards.com sells software to design your own cards and blank cards to print your designs on. Seems pretty cool, but it looks like you're limited to standard playing card sizes (i.e. no tiny Arkham cards). Their complete product line appears here. I'm not sure what size cards Bohnanza uses. I'...
Although not a particularly cheap solution, you could use a service like Artscow to print off this redesign of Bohnanza: http://boardgamegeek.com/thread/239278/bohnanza-redesign-for-the-uppish-and-the-posh
I've always just overbent the board at the creases, and it usually helps it lay flatter.
I use blank name cards. I get them from printers or stationers in boxes of 100 for about $1. They're smaller than regular playing cards, and not as durable, but you can also get them in perforated sheets of ten (10) that will go through your printer. You might find other sizes of perforated cards as well.
You could try adhering the card stock to modeling plywood (the <1/8" variety) to add rigidity, but keep the board from being too thick.
The simple answer is corrugated cardboard. Cheap and effective, but it looks bad from one end. Another option is to find a larger board from another game and glue your board to it, trimming the edges of the board and re-wrapping them with paper tape.
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