[fc]

I just finished building my own exposure unit with a 1000 watt MH bulb. I'm having a problem though creating a tight seal around my cover. I've installed weather stripping around the rim of the box, and under the glass. I'm using pond liner sandwiched between some 1X material. I have even layed down a bead of caulking within the sandwich, but still can't get a vacuum. Any suggestions on how to create a tight seal?

Thanks,

 

[foot print]

If your cover is on hinges.. You can attach 2 lock latches. 1 on each end to keep the it shut...if placed right it will add enough pressure to create the vacuum effect.

 

[fc]

Thanks FP.

I do have a couple of latches to lock the lid down. In fact, I have to push down on the lid to get the weather stripping to compress.

 

[foot print]

i attached a pic of how i set my vacuum top..i used a drip system sprinkler elbow and a threaded pvc coupling..sorry the pic is kinda dark..also did you give your blanket enough wiggle room or did you make it tight..?