box for 2 15 volfenhags

Always start out your box-building project by making sketches on paper.  This would be a sketch of the bottom of a proposed enclosure if I wanted to double-baffle the front:

Start with one of the sides of the box;  the bottom, being the foundation, is a good one to start with.  The sketch above would represent the bottom and would be as large as the limits of the exterior.  That is to say, the box won't be any bigger than this in any direction except up.  The side walls are shown as setting atop the bottom panel and their widths are shown for clarity in figuring true dimensions...much better than drawing simple lines for walls. 

The sketch would be labelled "bottom" and the side with the double baffle would be labelled "front".  Knowing that you are using 3/4" baffles, you know that the front will take up 1 1/2" of space and each of the other sides will take up 3/4" of space.  This sketch will give you two of the three dimensions you need for figuring cubic inches/feet.  Once you have another sketch done showing the side (or front/back) wall which will give you the third dimension of height, you will have the three dimensions length X width X height.  Just start out like that and put in all the proposed measurements inside and outside.  Draw in all support baffles and figure their cubic inches separately by using additional sketches.  Have it all laid out and checked over at least 20 times before you plug in the saw.

alright guys thanks for all the help u guys have givin, everythings already built , installed and thumping. the actually subs are pretty good , i was expecting worst, but the hit harder then when i had my 5 shhhty 12s. everythings good so far , no over heating , nuttin wierd. id give the setup a 6.5 lol