Anyone good with fiberglass?

[tegguy]

Ok I am working on my subwoofer enclosure and I am having a hell of a time trying to figure out what to do to get the cloth to lay right. I haven't tried to lay it yet but I don't think it won't look very good with the sharp edges. I have included a few photos of the box as it sits with the trim rings about where they will be when the box is build.

I am also going to try to put a chevy logo in the center of the box near the top and backlight it. I am probably going to fiberglass the whole top.

There will be a box or something built to decrease the volume of the box also.

I am trying to get the box to flow really good and the center will be inset from the subs.

I am thinking I need to
1)cut the vertical pieces on the sides so they are about half as deep as they are. so they would be shallower
2) Cut a notch into the center of the box between the two trim rings
3) Radius the edges on the top of the pieces (about the same curve as the trim rings)

Sorry if I can't explain very good but I'll do my best to answer any questions. Looking for some help here as I'm lost. To sum it up how should I modify this box to make the fiberglass look good and flow good with it's put on (IE No hard edges except ones that can't be seen)

 

[Grazz256]

I think the way its usually done is by pulling a piece of cloth (think t-shirt material or fleece) over the over the box. The cloth is light enough that the resin will pull it down a bit and make it look a little more natural.
For this to work you will probably need to split the box into two seperate halves or find some way to pull the center down.

 

[tegguy]

I think the way its usually done is by pulling a piece of cloth (think t-shirt material or fleece) over the over the box. The cloth is light enough that the resin will pull it down a bit and make it look a little more natural.
For this to work you will probably need to split the box into two seperate halves or find some way to pull the center down.

Yeah I have fleece that will be used and there will be a center divider to isolate the subs. I just don't know what i should do to eliminate hard edges like I would get at the corner near the trim ring if I were to drape it with fleece right now. Thats why I was thinking I need to cut them down so it wouldn't be a hard edge when the fleece is wrapped around to the back.

 

[kwb]

Around your perimeter where you staple the fleece before you get started with resin. Make sure the staples are to the inside and you have the hard edge.
This will give room for material thickness to build up and then you use filler (bondo) to create a much more sandable surface and radius to flow into the flats.

To add to the strength because really all you have holding the complex shape to the box are staples - I recommend running a tape strip of glass around the inside of box to the back side of fleece.

 

[tegguy]

Kwb also thanks for the information (also youGrazz I forgot to thank you previously)

If you see the 5th picture down you can see the corner of the wall piece sticks above and beyond the trim ring location won't this be a bad curve?

 

[tegguy]

I'm thinking I need to make cuts where the green lines are and remove the portion with green area

 

[Tribalvision]

Dont use fleece. I used grille cloth. It's a little more costly, but fleece will soak up resin like nobody's business and it doesnt soak evenly. The grille cloth will stretch nicer and use a whole lot less of the resin. The grille cloth layer will leave a strong enough base to work off. From there you can add the layers for strength.

You can add a center divider to staple the cloth to so it has an anchor point If you need a single chamber, just cut the center of the divider out and make it hollow.

I had a good tutorial on my site on how I built my box, but the site I hosted the photos on moved everything and the links are broken.

You can see in this build photo how my side dividers are hollowed out to make a single chamber box.

another image

You could always add a flat piece of wood secured to the center divider for your Chevy Logo. This will kill 2 birds with one stone. You'll have a location to secure your cloth and a location pad to mount your Logo. Place a hollow tube thru the box for your wiring for the logo.

Good Luck.

Edit* I decided to repair the images on my sub box page so everything is working right now. It may not be the correct way to do it, or the best procedure, but it worked well for me as this was my first attempt at fiber glassing. Six and a half years later and it's still perfect.

here's the link
http://www.tribalvisiontruck.com/newsubbox.htm

 

[tegguy]

Tribal that looks really cool and a lot of work. I just had one question

You could always add a flat piece of wood secured to the center divider for your Chevy Logo. This will kill 2 birds with one stone. You'll have a location to secure your cloth and a location pad to mount your Logo. Place a hollow tube thru the box for your wiring for the logo.

What did you mean by this? I was thinking about doing something like this (Sorry for the horrible paint drawings) It would only come out about as far as the bottom shelf. If you start from the left side of the box I'm trying to make the fiberglass flow out then back in at the center (top maybe a little farther out than the bottom) then back out when you get to the other side.

Edit: Where did you get the plastic for that LED piece and where did you get the LED's? That would work perfect to back light my chevy logo to match where my amps are going to go.

Edit2: Thank you so much for fixing the pics I was glad I could see what you did it looks awsome

 

[Tribalvision]

Add a center divider to the box right between the rings. Mount it to the back wall and the floor. Then add a piece of wood and mount it to the front of the divider and attach it to each ring with an air nailer. Similar to your drawing, but lower and centered. This will make a solid structure you can handle without worrying about the rings moving around.Then you can stretch the cloth over the rings and staple it to the wood piece. staple the fabric around the center block first. Then stretch the fabric outward and secure to the edges. I will say that making a plug type system for the rings will make it easier to glass around the rings.

The plastic I used was laying around from an old project. I initially bought it from McMaster Carr online. Im pretty sure it was a nylon sheet I had. I cant remember for sure, but they have toms of options you could use.

good luck

steve

Edit* I would remove the floor where you're green "V" is. it will be very difficult to glass there and secure it to the rings. But cut it in a nice slight curve to give the box some sleekness(is that a word? LOL) Plus it will not look right when done if left in. Also, shorten the side wall an inch or 2 and round the top and bottom corners so there's no point on the top of the box.. you want the fabric to stretch outward, not inward or straight

 

[tegguy]

Add a center divider to the box right between the rings. Mount it to the back wall and the floor. Then add a piece of wood and mount it to the front of the divider and attach it to each ring with an air nailer. Similar to your drawing, but lower and centered. This will make a solid structure you can handle without worrying about the rings moving around.Then you can stretch the cloth over the rings and staple it to the wood piece. staple the fabric around the center block first. Then stretch the fabric outward and secure to the edges. I will say that making a plug type system for the rings will make it easier to glass around the rings.

The plastic I used was laying around from an old project. I initially bought it from McMaster Carr online.

good luck

steve

Thanks Steve not trying to go against your advice but for layout concept I need to leave the logo box where it is. The rings do not go as far back as the center divider will be I could brace them with angle pieces but I'm afraid of messing with the "flow" of the fiberglass. I also need to decrease the volume of the box and that's why I boxed off the whole "shelf" area.

What do you think of my proposed cuts (green areas)? Will they be good to get the shape of the box to look good?

Edit: Thanks for the info on the plastic I wonder if I could find anyone who might have some locally. Did you get the LED's there also?

 

[Tribalvision]

the outsides of the rings look like they hang out further than the edge of the box. If this is the case, you will not have to cut much off at all. You want the fabric to stretch outward. so maybe an inch or so. The bottom corners, id chop off. it will flow better visually and you wont be able to see the bottom anyway. but the fiberglass will look like it's rolling right off the floor. As far as the LED's are concerned. I purchased bulk LED's from Ebay and added the correct resistors for the correct amount of LED's added inline.

Purchase the LED color you like and see how many you will need for your project. get the specs off the LED and use this calculator to find the correct resistor to use.
http://metku.net/index.html?sect=view&n=1&path=mods/ledcalc/index_eng

I used the same LED procedure for my box and my doors.

Build the box whatever size you like. Then use 2" pink Styrofoam glued and stacked to reduce the interior airspace. You couldalso screw a couple pieces of 2x4 together to take up some room.

not sure if you need it, but this is one of the best sites for car audio knowledge.
http://www.bcae1.com/

In all reality, you could make the LED blocks out of 3/4" MDF especially if using them for backlighting and no one will see them.

 

[tegguy]

I'll take a look at the site but I'm pretty good with electronics. What are your thoughts on the Hi Flux LED's verus the round ones?

So basically your saying to stop the side panels at the top of the trim ring (the point closest to the back)? I was thinking about rounding the bottom corners with the same radius as the trim ring and doing the same for the middle section.

 

[Tribalvision]

I really dont think it will matter how far back you cut the sides. It will mostly depend on how steep an angle you want the fiberglass to be towards the ring.

For the LED's, if you're going just for backlighting, I dont think you'll need the Hi Flux LED. A couple staggered LED's will work fine and they are PLENTY bright enough. I bought mine in bulk from Ebay cheap.

 

[Tribalvision]

If I were doing that design, I'd use a piece of 3/4 MDF and raise the wood off the box. I would mount the logo to that and back light it. It would look like it's floating in between the 2 woofers.

 

[03protege]

[/IMG]

This was my first fiberglass project and it took for ever but I learned a ton.

If you don't want sharp edges all I can really recommend is you do the obvious and eliminate them. The sides you may want to use a round over router bit on both sides to make it a round edge. I personally would redo the top. Also is that a port at the bottom? if you are looking for more shape you could put a center wall in and cut it to the shape you want.

I can make a picture if it would help.

 

[03protege]

Hope that helps some.

I can't tell the size of your rings but they looks a tad on the flimsy side, but of course it makes a difference what subs you are using.

You do not need to top piece to support the rings. Having them touch will give you those bad lines you do not want. I like hot glue and dowel rods, when you are done glassing you can tear it all out.

When doing boxes of this style it can be very helpful to leave the back off until you are done glassing. This way you can add your layers of glass mat without effecting the smoothness of the surface. This is a big bonus when you are ready to jam but instead you have to spend countless more hours with kitty hair, bondo, and milkshake method to receive that show quality smoothness (assuming you are painting).



MOST IMPORTANTLY: If you have not bought yourself a cheap little 3m respirator DO IT NOW. Fiber fumes are nothing to play around with and can really mess you up in short fashion.

 

[Tribalvision]

I agree with Protege on both points of leaving the rear wall out until your finished and getting a good respirator. I would remove the rear wall, but make a 1x3 brace across the rear top to keep the sides where you want them.

I was going to mention the rings looking a little whimpy, but they're already bigger than the face of the box. when I usually make large rings, I make 2 rings per driver. One ring will mount the Sub and the other will surround the sub mounting ring. This will flushmount them. I'm not sure if it will look right now for you, but I'd at least double the thickness of them.

 

[tegguy]

Sorry for my delayed response I didn't know there were people who had replied. I when ahead and cut my vertical panels back about 6" so they are just inside the back of the sub mounting ring. I also cut a half circle out of the middle bottom (I don't know if I'm going to like this I might have to seal it off with a rectangular panel and make a flat bottom front)

Protege do you think i need the top piece out of MDF or can I fiberglass all the way to the back? Also the rings shown are only trim rings i have mounting rings that are 3/4" MDF.

I don't have any pictures of my work today but below is what I did yesterday you can see the vertical panels the chevy logo will mount it (it will be in the location shown but at the top) They are also angled back by 30 degres.

I plan to get a respirator when I get to sanding the fiberglass I have a dust mask currently.
Also The back is already fixed to the rest of the box so I'll have to glass the front. Also the box at the bottom is simply an uprising to clear something in the trunk it's fully sealed. I am gluing and siliconing everything in the box to hopefully make it completely sealed.

Edit: I'll snap a couple pictures in a little bit showing the work I did today.

 

[Tribalvision]

The respirator is more for the fiberglass resin fumes you'll be inhaling. They are very bad for you. You could use a typical dust mask while sanding. wear long sleeves also

 

[tegguy]

The respirator is more for the fiberglass resin fumes you'll be inhaling. They are very bad for you. You could use a typical dust mask while sanding. wear long sleeves also

Long sleeves and baby powder I'll be glassing outside so I wasn't too worried about the fumes.

 

[tegguy]

some photos of the box as it stands right now (I'm 99% sure the center half circle will be patched)

Edit: I think I'm going to patch the half circle and cut the base of the box so it's behind the sub ring on the bottom

 

[tegguy]

I need advice one more time. I'm going to have a center area with a chevy logo that is backlit. What is the best way to ensure this will allow a sealed chamber on each side? Should I staple the cloth all the way around and rely on the bondo to help shape it? You can see it in the picture with the black Chevy logo look above it


The piece is only as far out as the bottom shelf and has a solid front for the bottom half

 

[tegguy]

Not much progress today but I was able to test fit the box. I had to remove my shelf spacer because it wouldn't fit with it in there I like the look what does everyone think?

 

[Tribalvision]

Looks good so far. Just give yourself 1/4" around where the fiberglass will be. Just so you know for sure it will fit when finished. Dont throw out those center plugs for the rings. After you stretch your fleece over the rings, cover the plugs in non stick aluminum foil, then screw the plugs back in place. it will pull the fleece a little tighter and will leave a clean edge around your rings when finished. just trim the fleece on the inside of the ring when finished.

 

[tegguy]

Looks good so far. Just give yourself 1/4" around where the fiberglass will be. Just so you know for sure it will fit when finished. keep those center plugs in the rings. After you stretch your fleece over the rings, cover the plugs in non stick aluminum foil, then screw the plugs back in place. it will pull the fleece a little tighter and will leave a clean edge around your rings when finished. just trim the fleece on the inside of the ring when finished.

I can't do what your talking about with the plugs cause it's one main ring with a trim ring and the main ring is screwed to the "stand" so there is no "plug" I was planning on stapling the fleece to the ring so the ring will stay there and the sub has something to mount to. Right now I should have a 1/4" all the way around I might have to make some adjustments to my trunk design after the box is built but that box slid in without removing the trunk springs which take up 1/4-1/2" alone.

 

[Tribalvision]

what's that round thing in the center of the subwoofer rings? It has to come out.

 

[tegguy]

It will come out I will router it out when the time comes. You might be able to see it in the pic below but it's basically a 3/4" piece the subwoofer will mount to once the center part is routed out. You can see the inner ring routed out and there are small pieces not cut that will be after the fiberglass

 

[Tribalvision]

ok, I see now. I didnt realize that was holding the rings. Ive never seen it done that way.. But that will work too, just glass right over it and then sand it a little and just router it out. that will give you a workable edge

 

[tegguy]

ok, I see now. I didnt realize that was holding the rings. Ive never seen it done that way.. But that will work too, just glass right over it and then sand it a little and just router it out. that will give you a workable edge

I thought it was the easiest way I didn't want to router out a single piece of wood. I will need to staple the fiberglass to the trim ring correct to hold the mounting ring in place when I remove the center piece?

 

[Tribalvision]

Staple the fleece around the edges of the box being sure to stretch the wrinkles out. Here's my problem with fleece. If you soak the fleece enough that it saturates completely through, it will attach itself to the MDF ring. It's difficult to really see if it's completely saturated unless you can see it from the other side. When you add the fiberglass mat on top, it creates one solid structure making the rings become part of the enclosure. You will only be stapling the fleece. There is no need to staple the mat because you will add the mat after the fleece has cured and created the basic shape.

 

[tegguy]

Tribal would you recommend stapling it (the fleece) to the trim rings incase it doesn't soak all the way through? I won't be able to see the backside as I'm doing the resin. Or do you think it's overkill and will require more prep in the end?

 

[Tribalvision]

Well, if the resin doesnt soak thru the fleece, stapling it wont help at all. The only purpose to the staples is to hold the fleece until the resin bonds it to the MDF. If it doesnt soak completely through, you dont have a decent bond. That's why I use grille cloth. It stretches nice and tight, it's very thin and uses minimal resin, and it's still a strong enough base layer that you can handle the project.

I only say this because as a rookie, I learned this lesson the hard way. I'm just trying to prevent you from making my same mistake. Now dont get me wrong, thousands of people use fleece as their base and it works fine. I just find it sooooo much easier to determine the soak thru with grille cloth.

 

[tegguy]

Well, if the resin doesnt soak thru the fleece, stapling it wont help at all. The only purpose to the staples is to hold the fleece until the resin bonds it to the MDF. If it doesnt soak completely through, you dont have a decent bond. That's why I use grille cloth. It stretches nice and tight, it's very thin and uses minimal resin, and it's still a strong enough base layer that you can handle the project.

I only say this because as a rookie, I learned this lesson the hard way. I'm just trying to prevent you from making my same mistake. Now dont get me wrong, thousands of people use fleece as their base and it works fine. I just find it sooooo much easier to determine the soak thru with grille cloth.

Ok I get what your saying. Is there any local places that might sell grille cloth? How much does it cost? I have some really thin fleece right now basically about a regular tshirt thickness or maybe twice that thick. I am hoping to be able to fiberglass this weekend.

 

[Tribalvision]

staples hold fleece/grille cloth to form the shape
fleece/grille cloth creates a workable base of the shape so you can add the mat to.
fiberglass mat adds strength to the enclosure to prevent flex and cracks
Bondo smooths out the curves for appearance.

that's pretty much the purpose for each step in the process.

 

[Tribalvision]

I ordered my cloth thru Parts express. It came quickly and it's fairly cheap. same day shipping the day you order. just measure your box and make sure you get enough. I'm not sure where you could get it locally. Radio shack used to have it, but I dont think they carry it anymore. Maybe try a fabric store if you dont want to buy online. My friend said he used spandex material, but I have no experience with it.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=260-335

 

[tegguy]

Tribal,

Once again thanks for the info. I am going to think about the grill cloth I hate to order it and it not show up in time. Let me ask there is there any issue with over soaking the cloth(I doubt it but I figured I'd ask). RadioShack doesn't sell much of anything these days except cell phones.

 

[Tribalvision]

if you use the fleece soak the **** out of it wherever it is touching the MDF. If you're not sure, soak it some more. The wood area is the critical area.
if the fleece isnt toally soaked thru on the non wood touching area, it will be ok. the fleece isnt there for strength, just for shape. You can add the mat after for the strength. You just want to make certain it's bonded to the wood.

Good luck and keep us posted!

 

[tegguy]

Thanks Tribal I think I'm going to chance it and stick with the fleece I have. I appreciate the warning and it might bite me in the a$$ but we'll see. I still have more to do before I get to the fiberglass stage though but I like the shape it's taking so far.

 

[Tribalvision]

no problem, good luck with it.

 

[tegguy]

Well I made a little progress today. I am hoping to have the fleece on tomorrow and fiberglass saturday!