[SIZE=+1]A quality computer style fan works best for venting. To make it simple, find a fan with 120/220 volt AC input. Try to find one with the most power (about 20 - 40 watts) and rated air flow (150 CFM's minimum). The squirrel cage style fan can provide more airflow if required. These may be rated the same CFM's, but have more power to vent out a long pipe. Try to plan the vent holes around the fans you are using. You can always modify the box with a new hole and patch an old one.[/SIZE]
[SIZE=+1]Have the grow box vent fan drawing air out the the box, and the light fan pushing cold air into it's area. This will ensure that no box odors escape other than the grow box vent.[/SIZE]
[SIZE=+1] Build two of these for the sides of the box. Glue the 2x2 lumber into place and place screws in from the plywood side.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Then make two pieces for the top and bottom:[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]For the front and back, trim the 4x4 plywood:[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Next, stand up the sides and place the top piece on. Once you are sure it fits, use screws to fasten together. Don't use glue here, in case you want to disassemble it later.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Turn the box over, and attach the other side the same way.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Attach the back piece in place, and check the door for proper clearance. You can use hinges for the door, or simply a small dead bolt in each corner.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]There are many manufactures and sizes of HID bulbs. To create the closed system, you have to custom make the frame to enclose the HID bulb you are using.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Build the frame to support the glass.[/SIZE]
[SIZE=+1]
[/SIZE]
[SIZE=+1]Seal the inside joints of the marijuana grow box with silicone sealant, and use weather stripping for the door. You can either use white paint or poly for the inside of the box. This gives you the best coverage of light everywhere. For hydroponics and sprinklers, poly will easily protect the wood and save you some trouble. You can also seal the base to contain the nutrient solution.[/SIZE]