Thread: False floor

Originally Posted by DJiK

Here you go:

That looks like "arrow in face."

to make a well built spare tire well box is actually easier than you think. There are many, many, many ways to build them, and you are literally limited only by your creativity and lack there of. Here is the basic process.

We start with the enclosure. whats the point of a spare tire amp rack if it doesnt hold your subwoofer too and give you 100% trunk space, right? you can make the box forom fiberglass or MDF, doesnt matter. I like fiberglass because its easy and maximizes available volume. But you can just build a box in there as long as you can bolt it down and it doesnt go anywhere as you drive, and its totally cool.

If you make a fiberglass enclosure, I like to make a frame of MDF or 1x3's, whatever I find. think like a picture frame, only its a hole where glass is. it sits on top of the spare tire well, in the well, as high or low as you want. I like to make it *just* high enough to fit the subwoofer depth itself and give it space to breathe. suspended there if neccesary, I mask the well off with tape and aluminum foil and lay the glass right on the well and exposed frame. it becomes one piece, the frame and fiberglass. I layer everything all at once, not layer by layer by layer, I just lay up glass on top of glass till I think its thick enough, and I have my tub.

Now I have a tub with a wood ring around the edge, sealed and ready for a baffle (for those who will read this who dont know, a baffle is the panel of wood you screw the speaker to). the baffle you will cut on the big side if you want. you will make it a big rectangle big enough to screw all your equipment to. speaker hole (make sure the speaker will fit in it!) amplifiers, crossovers, EQ, DSP,computer, fairy dust, dead bodies, however big it needs to be to physically fit in the car and fit all the equipment you are gonna install in it. maybe youll install nothing, jsuta subwoofer! but since you are asking about an amprack, probbaly you are gonna want amps in there too.

when you figure out what size you make it, make sure you fit it in the car, arrange the amplifiers how you think will look good/make wiring easy, etc. everything should be arranged all nice!

now find the tallest piece of equipment you have. If its an amplifier, its probbaly three inches tall. if theres nothing else in there, probbaly one or one and a half inches will do. anywyas, make a frame that tall around everything, one big square or rectangle. I usually use 1x3's or 2x3's, since ive got amps in there. you might find all you need are 2x2's. whatever it takes. make a border on top of the baffle, the false floor will rest on that.

okay. now you have your baffle, a hole is cut in it for the speaker, and its screwed to the top of the well shell. dont forget the silicone, liq nails, bondo, whatever you use to seal it up inot one piece! you now have a full box.

carpet or vinyl or paint, finish the walls. I like carpet best. this wont be seen as part of the trunk standard, so feel free to use what will match the equipment best, silver, grey, black, red, whatever. I like black because its cheap and goes with everything. but you can paint if you want, though that leads to problems later (youll realize why when we get there.) carpeting is real easy, just like doing a normal box, except its inverted. like carpeting hte inside of a box. worst comes to worst, you dont need to worry abotu the sides, since you wont see them anyways, but I prefer to do it all in once piece for simplicity.

okay, now you can put it in the car and wire it up. its not gonna leave the car again. I poke my wires through the 2x3 walls near the amps and run the wires under the amps. you can do what you feel works best. loom, screw, ziptie, hide under amp, whatever. this is part of that creativity thing!

okay. box, amprack, wiring, and an uglyass trunk floor with a nice square border and a show quality carpeted section in the middle. we gotta hide this!stock trunk floor pieces usually arent cut to form fit the trunk, so we gotta make our own.

all thats left is to make the actual floor itself. You can use .75 mdf, I use that often, I also use .5 inch baltic birch, whatever I have or wish to use. I like mdf best.

okay, to make the floor, you may have noticed a floor cut wont fit though the hatch, nor through the folded rear seats. maybe your seats dont fold. so we make it in three pieces to get it in there. two equal size pieces works, but is uglier since the seam is right in the middle in plain sight. so we make it in three pieces, one freaking huge piece in the middle, and two small chunks, one on each side. this makes the seams least visible.

okay! cut your first piece, the large one, a standard trunk gets progressively narrower as you travel toward the cabin, becomming narrowest about where the strut towers are, where the rear seats are. cut your floor THIS wide, long enough to go from front to back. this will be relatively easy. the seats part is flat, the two sides are flat. sometimes the side closest to the liscence plate will have a slight curve on it, you can eyeball it pretty easily.

now that that is cut, cut a hole in that. a nice big one, right over the amp rack. this is what youll see your nice carpeted rack and sub box through, so make sure you cut it at the right spot! I like to round the corners using a bondo can or something. rounded corners look better than a perfect square or rectangle, it softens the hole. you can cut it square, rectangle, superman logo shaped, a diamond, a huge circle, an L shape, a star, whatever you want. I like rectangle cause its simple and looks good. I like to cut it out not seeing the outside of the equipment, like ill only show three quarters or half the amps, a portion of the subwoofer, you dont have to see EVERYTHING in there! but get creative, maybe showing off everything is good!

okay, board and a hole. now cut some pieces of .25 inch board or 1/8th inch board about an inch square or two inches square and screw and glue it to the hole on the underside. make about a quarter inch stick out into the hole. this is what keeps the hatch cover you make from slipping through!

at this point, it looks like a single board that rests on top of that 2x3 frame of wood surrounding the amps and subwoofer with a hole in it, letting you see a flattering view of the equipment.

okay, one piece done, two to go! cut out some cardboard into strips of varying widths, about a foot long, between one inch and four inches wide. now grab a scrap piece of wood and place it into the trunk at the same height as the floor. I usually just set it on the center piece of floor and use it. now take your strips of cardboard and push them up against the wall of the trunk. nice and flush now! the tail will be long enough to rest over that scrap board, and staplegun the cardboard to the scrap wood. continue in this way across the gap you dont have a false floor over yet, and you end up with a perfect contour of your trunk, and more importantly, a perfect contour at the height of your new floor! okay. pull it, trace it, cut it, and you've got one side cut! do the same for the other side. now cut a piece of MDF about four inches wide. it will need to be tall enough so that when you glue it to each of the side pieces, they will sit at the same height as the center floor. should be a few inches.

sit the pieces in the trunk, and you should have a perfect model of your trunk floor in .75 mdf. just a little ugly

okay, this is what you see all the time, so make sure the carpet you get matches the trunk walls perfectly. now you glue it across the top. ALL of the top, all three pieces! the carpet becomes the hinge, itll work, I guarantee! lay the carpet on your driveway, glue the center piece on, strech nice and tight, then line up the two sides and stretch the carpet right over that piece too. also watch for the several nubs glued up over the hole in the center piece, make sure it looks nice.

heres is when this gets beautiful. flip the board, FOLD the sides on top of the carpeted center board, and itll slide right into place! then fold each side, one then the other, use your hands to smooth out the sides, and its PERFECT. perfect, perfect, perfect false floor with a SEXY view of a nice carpeted panel with subwoofer and amps, everything. the carpeted lower piece, that carpet will rest between the box and the false floor itself, so nothing will rattle. you can even screw neon lights to the underside of the false floor, and the light will shine down on the amps and woofer!

all you need now is a cover. I try to use thinner board than the floor is made of since the carpet has a thickness, so it sits a bit higher than the rest of the floor if I use the same thickness material. in our case, grab some .5 inch MDF, cut it into that shape. dont forget to make it a tad smaller, since the carpet itself has some thicknes to it! cut a hole or two into the board where the subwoofer is to let it breathe.

now youve got two options. #1, cover it in grill cloth and install it, call it a day. this is super easy, but I dont like it. the texture of the cloth is diferent, the color often doesnt match, and you can toss any old think into the trunk without thinking about whether or not its gonna hurt the cloth. that defeats the purpose of a stealth false floor!

I like to use the same carpet I used for the false floor. bass will make it through just fine. but it stretches, so we need to support the hole. so I cut a piece of perforated aluminum and bondo or silicone it in place, after routing out a groove for it to rest into. Everything rests at the same level, and the carpet is a perfect match.

installing the hatch, and I am left with a trunk that has a floor about three inches tlaler than stock. its seamless minus a square hole with rounded corner seam in the middle. I can huck golf clubs or a drum set back there and its perfect looking.

and when I lift the hatch cover, I have a show quality install to show off, neons, carpet, subwoofer, anything I want.

feel free to ask any specific questions if theres something I can clarify.

any pics to go along with that write up???