I bought one of these at Wally world today ($40.00) & as I was going down the isle I spotted a plastic cake plate with a large dome like cover & the little brain started clicking. So I thought self, instead of hoging out the trays to accommodate width & height, the cake lid would allow for lots of height & still maintain the integrity of the unit. I ran a temp comparison with both lids using a digital thermometer & they came out with a 5 to 8 degree difference. There is no other switch on this unit but the on & off switch. I tested a plastic spoon by painting it with a rattle can so we'll see. My main concern is the temp & how long should one leave it in the dehydrator and what temperature does plastic melt anyways?