Would like the box to be completely sealed. I have foil tape around every seam except the front. Any suggestions for the gap between the doors in the front and around the edge of the door? I have weatherstripping there but it isn't working well. Thanks guys!
Where the two doors meet you are going to need to put something behind it (on one door). You can use a cut piece of wood, or a door sweep will work (a door sweep is something you put on the bottom of your door to keep drafts out - usually made of metal and rubber). The idea is that you attach it on the back of one door, and when the other door closes (on the other side) it creates the seal. Now on the other 4 sides, your going to have to use more/different weatherstripping. If the top/bottom has a flat surface that you can attach "peel and stick" stripping to, do that. Now on the hinged sides, you'll need a different type of weatherstripping. I used the type that you'd buy for a storm door. Its pretty cheap (about $10 for enough to do 4 cabinets your size). Its made of aluminum and rubber and comes in long packs that are around 81" (about the height of a door). Your going to cut this in lengths with some tin snips (or use a hacksaw) and attach to the inside of the cabinet, so when the door shuts you get a tight seal. If you view the first page of my grow journal (in my sig), you'll see I had to do exactly what your trying to do. Hope it helps, PM me if you have questions (I'm a somewhat retired carpenter BTW) - dunno much about growing bud, but if its made of wood I can fix or build it
Look at where the hinges attach. Maybe they just need to be mortised a little deeper so that the door backs sit flush with the cabinet body.