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Nice feet! :D

Bob The Eskimo

"Nice feet! "


Scary. . .

Mafia

Here check this setup

Bob The Eskimo

drool . . .

but I need practical as well.

Need For Speed

thats macnific!!!!

Bob The Eskimo

I have a question to ask.

I have been sealing the box lid in place over the past few days and have found it to be a bit more time consuming than I first imagined.

I began by tapping and screwing the baffle into the sideboards, then I began to wrap fiberglass on the outside just thin enough to get a seal (i used the cloth rather than the mat which seems to flex a bit more), and tonight I will fill in the open places on the inside with more fiberglass resin. After that drys, I plan on using clear caulking to fill in any remaining gaps.

Does anyone have a better way of sealing the box?

I think for the second section of the box I will try to set the sideboards in place while the fiberglass is still drying. I may even try to have the sideboards, and the baffle already screwed together and place it all in one piece. Any thoughts?

Bob The Eskimo

Ok, I probably chose the hardest way possible to seal the box up but I am going to work through it. Let's start with a photo.

Bob The Eskimo

What I have done in the above picture is as follows.

Once the fiberglass is cut so that the baffle board lays as flat as possible on top of the box, begin to seal the outside edge of the box as air tight/water tight as possible. I was careful not to go higher than the baffle. You may find it helpful and adds extra strength to go higher than the baffle, but The second portion of the process is what will hold the pressure, not this layer.

Go the whole way arround the box and seal it as well as possible. Then go to bed and come back tomorrow.

Bob The Eskimo

After the glass has dried, come back and we will work on the inside of the box. Take some fiberglass mat and in any large areas, stuff small shreds of the mat. Then mix up some resin and strategically pur the resin into the cracks or opened spaces. Don't be afraid to over pour the spots. It will only add thickness to the box. You will also want to pour resin arround all of the openings/cracks/seams or whatever holes may exist. This when hardened, will give the box a perfect seal.

At this point sleep, and then come back and go over these areas with caulking. This is an extra seal that never hurts to have.

PUR NRG

Okay, now I can visualize what you are doing.

1. By glassing over the wood, won't it prevent the two halves from fitting together snugly?

2. Have you heard of the stuff they use for automotive window calk? It's a black urethane that's flexible but adheres well. You might try using that as glue to attach the wood to the fiberglass. You can also use it as "regular" calk afterwards.

3. There is also a type of bondo that contains fiberglass strands mixed in. I hate working with the stuff but might be what you need for sealing/reinforcing. However I'd still recommend the window calk. It seems like flexibility would be good to help absorb woofer vibrations and it's lighter than bondo.
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Body Science

Bob The Eskimo

Yeah, That's exactly what I wanted to do with the window caulk. The thought was to seal the outside with fiberglass cloth, let harden, then pour resin in the sides (from the inside of the box) to fill up any major cracks. Then the smallest holes will be filled with caulk.

PUR NRG

Plain resin is brittle. How will to hold up to continued vibration from the speaker? It isn't a very good adhesive on its own either.

That's why I recommended the automotive urethane window calk. You could apply a thick bead along the board's edge, press it into place and after it cures use a razor blade to trim the excess that squeezed out. It would give you an airtight, strong yet flexible bond.
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Medicinal Marijuana Melrose

Bob The Eskimo

I agree with you. Caulk is probably the best way to go. I was just affraid to do this in the larger gaps that were left between the board and the glass. The caulk has some flex that I was concerned with under SPL, but I think I overcame that with the outside layer of glass.

Resin is brittle by itself, but it bonds very well to other glass and to pourous wood surfaces (MDF). I should have some more photos this weekend.

On a side note, I feel like i just graduated. I got rid of that 'junior' next to my member status. I finally have enough posts!!!

Bob The Eskimo

PUR NRG

I forgot to post a reply to question 1.

The two halves are not going to fit together snugly. There will be about 1.5 inches of space between them, with the passenger side baffle board being larger than the box. This will allow the appearance of two connected boxes for the false floor, but allow enough wiggle room, that the boxes can be moved and removed from the trunk easily.

I would be on the second box by now, but sealing this thing up takes one day per side to dry. What a pain.

rjacobs

Well if you are not concerned with looks, I would say as long as you can get the edges of the MDF to get pretty close to the fiberglass, you could put a fat bead of liquid nails on it and then run screws through the fiberglass and into the MDF. That will seal it perfectly. That is how I have always connected my pure MDF boxes together. I am looking for measurements of just the little recessed area in the floor so that I can see how much airspace is in that and also what the depth is. I am thinking about just building a box for a single 12 in the recess if I can get enogh airspace and depth.

Bob The Eskimo

If I remember correctly the recess is about 1,592.5 cubic inches if you leave about 2 inches at the back for the opening of the jack hatch. This is about .9 cubic feet. The 12' would need about .75 feet of breathing room after you take into account the displacement of the magnet and shell. The two 12"s that I have require about 1.25 feet each. There may be models out there that requre that amount.

Also, The look of the box will be carpeted to match the rest of the trunk. You will not even be able to tell that it is glassed.

Bob The Eskimo

Ok, it's been a while because each step I had to seal one side of the inside of the box. I used fiberglass resin and cloth, and then in the small areas with holes I used window caulk to fill in.

Now I am left with a perfect seal. It just took forever because each side took a full day to dry.

Take a look.

Bob The Eskimo

yes I know it looks like crap, but it will all get better soon.

I was not concerned with the image of the box without the carpeting on it, just that it had a perfect seal.

In order to double check that I had a perfect seal on everything, I lightly placed the speaker in the box. With a flat hand I gently pressed on the speaker cone and listened for any leaks that were audible. I also ran my hand around the box slowly to detect any leaks by touch.

Once you have a seal in all areas so that you are comfortable with it, we begin smoothing things out. Take a sander and sand out all of the rough spots, high points, outcroppings, and other stray pieces, and make it fit your trunk perfectly. Have the whole box smooth to the touch. At this point it still may not look perfect, but that is ok.

Bob The Eskimo

now that the box is sealed and sanded, it is time to puncture it for the wires. I was never a fan of placing any un-needed connectors, so I opted to run wires from the speakers directly to the amps rather than a connector at the side of the box.

Simply drill a hole in the sidewall of the box wherever you see fit, and then run wires to the speaker. Internally, I made sure the wires dont rattle against anything by running them through the speaker frame and removing any slack that would be available. Once you have the Wires in place and the speaker in, use window caulk from the inside and out to seal any remaining space in the hole.

Bob The Eskimo

now, bolt the speaker in.

Here is a pic of the setup in the trunk so you can get a feel for what It will look like when the entire setup is done.

Bob The Eskimo

Here is another angle. i built it this size for easy access to the jack if needed.

Bob The Eskimo

I also have about 11" of clearence over the top of the box (and amp when installed) so that golf clubs, or luggage would fit.

I could have mounted the speakers inside the box for added room, but decided I would rather have removable speakers than, recessed subs.

I will install a grill or plexiglass cover after completion. for now, there is a large amount of room in the front end. The amp will ride across the top of the boxes, but will still allow 10"-11" clearance.

Bob The Eskimo

Over the next few nights, I will carpet it and finish it up before begining on the other side.

rotarygod

I wish I would have seen this earlier. The easiest and most sure fire way to seal up the inside of your box is with a combination of bondo and fiberglass. This is something that we just experimented with one day at the shop and found works extremely well.

To do this take a large plasic cup and fill over half full of just pure bondo. Then add a small amount of fiberglass resin to the cup. It doesn't take much. You want just enough that it will run but not so much that it is watery. Now add the Bondo hardener only. Do not use the mekp fiberglass hardener. Mix this together and then pour it into you box. Now hold you box up and turn it around watching the mixture coat everything inside. It is pretty neat to see since it sticks to everthing inside. You may have to do this process a few times to make sure you coated the entire inside well. It hardens within only a few minutes just like bondo does so you've got to be pretty quick.

Your box will never leak with this method. It is very easy to do. It also adds a little thickness to the box as well as giving the interior a very nice smooth finish. I never use caulk in a fiberglass box. Try this method before you carpet it. Remember it is easier to do it right the first time than it is to do it again.

Bob The Eskimo

now that sounds like a good idea. Thank you god.

rotary god that is.