1. Last month, we fiberglassed the speaker enclosures for the top of the RV. Now that the fiberglass has cured we can finish the construction process.
Last month we started building speaker enclosures for the roof of an RV. Since these enclosures are weatherproof, they can be permanently mounted to the roof and fit with marine speakers. We'll show you how to finish them properly and next month we'll cover the installation process. Send questions to techpanel@sourceinterlink.com with Tricks of the Trade in the subject line, and check out stevebrownuniversity.com
Last month, we fiberglassed the speaker enclosures for the top of the RV. Now that the fiberglass has cured we can finish the construction process. After the carpet has been fiberglassed, it ends up with a rough texture. This texture must be removed with an angle die grinder. A rough 24-grit disc works best to smooth out this texture quickly. These enclosures will be exposed to the elements on the roof of the RV, so we decided to use PVC pipe to run the speaker wire. A 90-degree elbow fitting was molded into the back of each enclosure to allow 3/4-inch pipe to fit inside. The 90-degree elbows were tacked in place temporarily using superglue and permanently attached with fiberglass-reinforced body filler.
Rage Gold body filler can now be applied to the surface of each enclosure to fine-tune the shape. This picture shows the proper ratio of filler to hardener. A scrap of wood or cardboard makes a great mixing board. The Rage Gold is spread evenly over the enclosure surface using a spreader. Wearing latex gloves, use your finger to smooth out tight spots. The Rage Gold will start to cure in five to 10 minutes and will have a clay-like consistency for another 10 minutes until it hardens completely. Since it's much harder to sand when fully cured, this clay stage is the best time to sand with coarse 36-grit sandpaper.
The first application of body filler will take care of most low spots on the surface. Sometimes it's necessary to mix one more small batch to fill any remaining low spots. Polyester primer is excellent for finishing parts like this, since it cures evenly even if it is sprayed on thick. Mix 20cc of fiberglass hardener per quart and the primer will cure in three to four hours. Spray three to four wet coats of polyester primer on the enclosures, waiting five to 10 minutes between coats.
2. After the carpet has been fiberglassed, it ends up with a rough texture. This texture must be removed with an angle die grinder. A rough 24-grit disc works best to smooth out this texture quickly. | 
3. These enclosures will be exposed to the elements on the roof of the RV, so we decided to use PVC pipe to run the speaker wire. A 90-degree elbow fitting was molded into the back of each enclosure to allow 3/4-inch pipe to fit inside. |
4. The 90-degree elbows were tacked in place temporarily using superglue and permanently attached with fiberglass-reinforced body filler | 
5. Rage Gold body filler can now be applied to the surface of each enclosure to fine-tune the shape. This picture shows the proper ratio of filler to hardener. A scrap of wood or cardboard makes a great mixing board. |
6. The Rage Gold is spread evenly over the enclosure surface using a spreader. Wearing latex gloves, use your finger to smooth out tight | 
7. The Rage Gold will start to cure in five to 10 minutes and will have a clay-like consistency for another 10 minutes until it hardens completely. Since it's much harder to sand when fully cured, this clay stage is the best time to sand with coarse 36-grit sandpaper. |
8. The first application of body filler will take care of most low spots on the surface. Sometimes it's necessary to mix one more small batch to fill any remaining low spots. | 
9. Polyester primer is excellent for finishing parts like this, since it cures evenly even if it is sprayed on thick. Mix 20cc of fiberglass hardener per quart and the primer will cure in three to four hours. |
10. Spray three to four wet coats of polyester primer on the enclosures, waiting five to 10 minutes between coats. | |