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This past month I had the pleasure of visiting JL Audio's factory in Miramar, FL. After seeing some of their processes in the Stealthbox enclosure area, I came up with a cool idea for this month's how-to. JL Audio's processes involve making their enclosures out of various molds for different vehicles. When finished, these enclosures are almost perfect in shape. This allows you to modify and get a more custom look for that customer who wants some flash without spending a week or more in labor. This month is part one of a two-part project involving fiberglass inserts and two-part urethane foam. Tune in next month to see the final steps!
 Here is the 350Z Stealthbox....  Here is the 350Z Stealthbox. This enclosure fits behind the rear strut bar in 2003 to 2007 Nissan 350Zs with subs facing the rear of the car. This enclosure came to me with black carpet. I removed it and cleaned off all upholstery glue with a terry cloth towel and acetone. |  Here I've masked off the face...  Here I've masked off the face of the enclosure to prepare to lay the fiberglass inserts. |  Apply mold release wax over...  Apply mold release wax over the entire foil surface. |
 If possible, try to cut the...  If possible, try to cut the fiberglass in full sheets. Apply five layers of 1.5-oz. fiberglass mat for a total thickness of approximately 3/16". |  After you're finished applying...  After you're finished applying all five layers, use a fiberglass roller to smooth out any air pockets. It's handy to keep a tray with lacquer thinner to dip your roller into during this step. This will keep the roller from gumming up with resin. |  After the fiberglass is dry,...  After the fiberglass is dry, remove the insert and use an air saw to cut off the excess edges. |
 Once the insert is cut, place...  Once the insert is cut, place it back and sand the edges until you hit the enclosure. |  With inserts in place, drill...  With inserts in place, drill three holes that will be used to place fasteners. I will epoxy three t-nuts inside the enclosure. |  With a router and a perfect...  With a router and a perfect circle base attached, make an MDF ring template to trim around the cone of the speaker hiding the mounting screws. |
 Save your template and make...  Save your template and make duplicates on a router table with a flush-tip router bit. I've used 3/4" MDF for the rings. Remember to ALWAYS cut out the excess material with a jigsaw first. |  |  Use the rings to mark the...  Use the rings to mark the fiberglass. Notice the JL Audio logo in the center of the inserts. This will be used later to hide a mounting bolt. |