got some box making questions

I would recommend that you bolt them to the floor from the inside of the box...and use T-nuts with allen bolts...that should make it pretty hard for thieves

 

When I figure my cu. ft....this is what I do.....

To start....yes 1728 cubic inches is one cubic foot...12x12x12.......

So to make it simple, let's say that I need 1.5 cu ft for one driver.....so that would be 1728x1.5=2592......I figure the height and width of the box to fit the space....Lets say I can do 18" wide and 12" high......I do this....

18x12x20=4320....way too big.....let's try 18x12x12=2592...that is a match..Since you use 3/4" material for the box, you have to add 1.5" to each side.....19.5"x13.5"x13.5".....

You can basically change all the dimensions to match the size and come up with the cu. ft....Only thing to keep in mind is the mounting depth of the driver, that will give you a minum dimension for that....

Particle board is acceptable, but MDF is better....MDF is a denser material than particle board....Denser, means less flex, stronger and less resonance from the box......Please do not mistake OSB (oriented strand board) for particle board....Do not use OSB and do not use plywood....You want dense material....

When you assemble the box, use a good wood glue...Glue every surface that meets with plenty of glue....also.....use a coarse thread drywall screw or better yet, a deck screw.....Pre-drill the holes and if you can, counter sink them....I would recommend putting screws about every three inches....if you had the abilty and/or tools to do it, using dado joints would be better than simple butt joints....If you use butt joints, I would recommend adding the sealant at the joint lines as you go and after you cut the hole for the driver, try to get any corners you could not get before...Using a table saw (correctly set up and adjusted) to cut the wood is the best bet on straight square cuts...

Willy