You'll also need something like a wood block under the juice tray. The perimeter of the Norwalk juice tray is a "gutter" to allow the juice to drain out while the bag is under pressure. Otherwise, a little juice would remain in the tray and get sucked up into the bag again when the pressure is released. So you'll need something like a wood block smaller than the overall dimensions of the tray for the tray to rest on, that will allow the tray's gutters to hang over the sides and not get crushed when the pressure is applied.