If you want to fill or overfill an area leaving behind either a concave or convex surface profile, I would use something like Kitty Hair or Fiber Strand, both of these are fiberglass reinforced body fillers. These fillers allow the user to mold complex shapes and are easy to shape while curing with the use of a coarse, grater type body file.

But one thing to consider when adding a contour to pods and panels is the ability to cover the finished piece with vinyl or whatever material you choose. If your final profile has large round contours it will be hard to cover without getting wrinkles or needing to be stitched, so try and keep the profile a series of smooth transitions from one point to the next.

Imagine a suspension bridge, and the way the main cables stretch from one end, across the towers, and to the other end. If you first stretch some open weave knit fabric (t-shirt, grill cloth...) over your entire project you will be presented with a natural, smooth connection from the low to the high point and back to the low again. Use the filler to reinforce the established contour and also to build-up any deep contours that will be hard to cover as well.

Good luck.

SuperJohn: in answer to your questions;

1. when making a sub box, should i use large square pieces, or long skinny strips of fiberglass?

A: If you are able to work with large pieces then do so. The less you cut the fabric, the stronger the finished panel will be.

2. walmart carries fiberglas mat and fiberglass cloth i think it is, they are both in the same looking package, which one do i want for my enclosure? 7-10 layers

A: Either one will do, however there are some benifits to using the cloth as opposed to the mat.

With the cloth you will get a smoother finish that requires less sanding and smoothing before you can cover it, it will be somewhat stronger as well since the glass fibers remain mostly intact.

As far as my Great Stuff idea, could I use that for the majority of the build-up and then spread the kitty hair on top of that to get the final shape? I have used expanding foam several times, so I am comfortable working with it.

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Originally posted by strawmyers:
Thanks for the info, but that leads to another question. I'm going to need to build up the areas quite a bit (from 1-4" depending on the area). So how thick can you apply the kitty hair or fiberstrand at a time w/o the outside drying too fast and cracking?

As far as my Great Stuff idea, could I use that for the majority of the build-up and then spread the kitty hair on top of that to get the final shape? I have used expanding foam several times, so I am comfortable working with it.

[ 11-13-2001: Message edited by: strawmyers ]

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Personally, for what you want to do with the build-up (I'm assuming you want to use the contour as part of your enclosure), I'd use floral foam. Cut and glue blocks of it, then shape. It's much easier to get a nice smooth contour, and if you're using fiberglass cloth, it provides a smoother surface for the layup. The foam can be removed after the glass is cured.

Otherwise, just drape fabric over the project as Mabeita suggests. The contours will be nice. It works for me.

Start the project by covering the multiple layers (base, baffle, and supports) with some grill cloth or an old t-shirt and resin, doing this will establish a preliminary shape and lessen the amount of filler needed to get your final contour.

i have EVERY tutorial you've written saved, and some others. =)
im going to put together the full "How to build anything you desire. By: Mabeita" =)

now i want to use 1" or 1.25" dowels to brace the box. should i just screw these in through the fiberglass? or should i drill a hole through the box stick the dowel in and FG over it? the second idea seems to be easier in my case, but i think if i don't put a lot of FG over the dowel that it won't be attached well, and if i use too much FG the box won't fit into the car right, cause it's molded perfectly to the shape of the car.

i will have better pics tomorrow if you need them.

here it is installed:

and here's a shot to show how tight it fits:

But if you're going to attempt adding it, not a bad idea, then I'd suggest that you cut the pieces of dowel to length and test fit them by inserting them through the woofer holes, try to leave as small a gap as possible betweeen the ends of the dowel and the inside of the enclosure wall. Once you have them fitting snugly in place, mix up some epoxy resin and glue them in position. After the resin sets you can add a layer or two of fiberglass cloth tape to cover the joints at each end of the dowel. The addition of the cloth tape should make the joints as solid as a rock, with no real need for screws or drilling a hole in your enclosure, which would weaken it.

Just be sure to use epoxy resin, as it has greater bonding properties than polyester resins do, and if you can't find cloth tape, normal cloth will do, but the finished edge of the tape would make it easier to handle in such tight quarters.

I am mostly focused on the electrical and mechanical areas of automotive work, though I've been becoming more interested in designing and building a practical custom audio system for my car.

After reading both your Plexi and Fiberglassing posts, I'm anxious to go plexi or fiberglass something just for fun. And if anyone out there has any of Mike's other DIY posts, please link me or forward them to me

I think these particular threads should be saved as articles and posted as dedicated DIY web pages for printing.

The information you provide has me thinking or wondering what I can make with this stuff...I need to see some more ideas and projects to get some ideas on where I want to go.

But again, thanks...I'd love to work with you.

Now for my questions:

1. When doing kick-pods for a vehicle, if the stock kick panel trim piece overlaps into the rocker panel area where the door weatherstrip seals on and the overlap of the plastic covers a raise sheetmetal seam, is it better to make a mold of the stock peice and use that as the back to your baffle/pod, or use the practice of making an area mold of the "corner" of the kick-area? I have a '87 Buick Turbo Regal that I'm trying to decide which method is optimum, and then, dependant on that, how to make a mold of my stock plastic kick panel since the plastic is quite flimsy.

2. When trying to make a mold of a section of the car, in my case, the area behind the back seat in the trunk that is perpendicular to the ground, how do you keep the fiberglass material in place when working against gravity?

3. I was talking to a local car audio shop installer who was at a Kenwood sponsored seminar and they brought up mixing Evercoat Rage Gold or similar product in with resin. Here's the info I had him fax to me

- use any body filler
- omni primer (polyester primer works best)
- MEKP liquid hardener (will work with paste)
- use non-backed fleece, stretch and then coat with resin mixture
- mix bondo and fiberglass resin in small amounts (5-10oz) 50/50
- do not overlap coatings

He told me that the tech explaining this had a demo kick-pod that people were leaning on and practically standing on and it wasn't cracking or giving at all.

Additionally, is there anyone who lives relatively close who is into this stuff? I'd like to see some other people's work. I've been through the IASCA site and it doesn't look like there are any shows anywhere near me. I'm in Manahawkin, NJ ... and hour East of Philly. Anyone out there?

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Originally posted by darkfa8:
1. When doing kick-pods for a vehicle, if the stock kick panel trim piece overlaps into the rocker panel area where the door weatherstrip seals on and the overlap of the plastic covers a raise sheetmetal seam, is it better to make a mold of the stock peice and use that as the back to your baffle/pod, or use the practice of making an area mold of the "corner" of the kick-area? I have a '87 Buick Turbo Regal that I'm trying to decide which method is optimum, and then, dependant on that, how to make a mold of my stock plastic kick panel since the plastic is quite flimsy.

If you can attain a set of kickpanels that are of no permanent concern to you, find a set in a salvage yard, then you can do what I like to do, use the salvaged set as a base for your pods.

Take the replacement set of kickpanels and cut away any plastic that would interfere with the mounting of speaker components and create a frame that you can attach the necessary speaker baffles and support system to. Just remember not to cut away too much of the donor panel, a flimsy frame will shrink and twist when you attach the covering material, this will result in a pod that does not fit well.

Next assemble the newly created frame and your mounting baffles or rings and cover with some fabric to span the distance between the edges of the donor panel and the mounting surfaces. This can be followed with a few layers of fiberglass cloth, body filler, and finally some surface sanding for a smooth finish before covering with vinyl or lime green shag carpet.

Finally, pay particular attention to the edges of the panel that form seams near the door sill panel, making sure to blend the fiberglass and covering material with as little added height or thickness, you can even sand away the added fiberglass until you reach the original panel material so you can cover the entire pod with vinyl and impact the fit in the least possible manner.

2. When trying to make a mold of a section of the car, in my case, the area behind the back seat in the trunk that is perpendicular to the ground, how do you keep the fiberglass material in place when working against gravity?

First mask off the area that you want to create a mold of, then apply a coating of PVA or moldrelease wax, then paint the surface with a coat of laminating resin to begin the process.

Once the resin has set you can use it's surface tack to assist in holding the following layers of cloth and resin in position. Progress will be slow since you'll probably want to apply a single layer at a time to avoid the possibility of a landslide.

Laminating resin stays tacky for an extended length of time and is very useful for this application, it should be used throughout the layering process. The final coat of resin, on both inside and out, should be surfacing resin, this will form a hard shell and cover the laminating resins tacky surface.

3. I was talking to a local car audio shop installer who was at a Kenwood sponsored seminar and they brought up mixing Evercoat Rage Gold or similar product in with resin. Here's the info I had him fax to me

- use any body filler
- omni primer (polyester primer works best)
- MEKP liquid hardener (will work with paste)
- use non-backed fleece, stretch and then coat with resin mixture
- mix bondo and fiberglass resin in small amounts (5-10oz) 50/50
- do not overlap coatings

He told me that the tech explaining this had a demo kick-pod that people were leaning on and practically standing on and it wasn't cracking or giving at all.

Mixing of resins and filler does seem to be very helpful to some people and I've been told that it is easier to work with than fiberglass layering followed by filling and sanding. My advice to you would be to try it on a small project first and work up to use on larger pieces.

I've never used this process, but have worked along side those that have and not noticed much in the way of increased speed or final quality. But as with any method of fabrication it might work great for some while others just keep getting the mix wrong.

so...anyone wanna come over and plexi and fiber 'glass some stuff?

Two round trip tickets will get you a weekend of learnin'.

[/QB]

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see the thing i was going to do with the dowels was sorta angle them, so that say one went from the middle of the back of the box to the middle of the front of the box. this way the brace would be most effective. but in order to do this, the brace would have to be angled, and then contoured to fit the shape of the back of the box.

would it be as effective if the brace didn't fit the exact shape of the box?
will the epoxy resin bond properly with the polyester resin?

thanks for the help

basically im asking how much i have to save up before i start, cuz i hate unfinished projects and would like to have everything purchased and layed out during my first time starting.

how many packs of the fiberglass cloth/mat?
what size container of resin?

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Originally posted by GlasSman:
Ok.....I'm pretty good at this stuff. But due to my recent laziness there's one type of project I'm curious as to how the "experts" approach it. And I'm sure this is something MANY others also wonder about.

Trim panels in the trunk that fit perfectly to the rubber weather stripping that surrounds the trunk opening. Getting the contour and overall shape of the panels is no problem. I thought of just taping the entire area off and glassing the weather stripping area. Then use these pieces as a starting point after trimming for the rest of the panels. Just wondering what approach you would use for perfectly fitting trim panels.

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