The length and width of my teardrop is bigger than a standard sheet of plywood, so I needed to connect a few pieces together. I chose to use a biscuit jointer, and then use fiberglass and epoxy to strengthen the joint. In this image, I'm using a flush trim router bit to cut the plywood to the exact size of the trailer.
Before I routed the plywood down, I attached it to the trailer frame using stainless steel carriage bolts, washers, nuts, and zinc torque washers. The torque washer has mini pins that gouge into the wood, preventing the carriage bolt from spinning, thereby getting a tighter turn on the lock nut.
I tried to find stainless torque washers without success. So, I painted mine with primer. These will never be exposed to weather, so probably a worthless step, but I did it anyway.
Here is the fill sized primary deck, sanded down on the joint. I saved a few bucks by getting UV coated birch plywood, but I had to sand this outer coating off so that the epoxy would have something to stick to. If I had to do it again, I would have payed the couple extra dollars for the normal birch plywood. You can see the attachment carriage bolts surrounding the frame.
This is going to be a raised deck, with the electrical and ventilation running underneath a secondary deck. I'm using 1x2" poplar boards in between the 2 decks. Here are the outside edges clamped temporarily into place.
Fiberglass cloth taped down and ready for Epoxy
After the epoxy is applied, the fiberglass cloth becomes transparent. Once this dries, I will flip the board over and repeat on the other side. This should create a very strong joint, using a combination of Biscuits and fiberglass to hold all 3 sections together.
I'm also planning on running the AC ventilation in between the raised deck. There isn't enough room simply by using the 1/2" poplar boards, so I used a Dado bit to remove some material in the deck where the vent till go.
Since plywood is 3/4", and I removed almost 1/2" of material, the sheet is a little thin around this area, so I chose to use fiberglass to strengthen the lowered section.
Next Steps is to remove all of the bolts holding the sheet to the trailer, flip it over, and seal the joints on the other side with epoxy and fiberglass. The entire underside will be sanded, and then I'll use a truck bed liner to seal anything that will be exposed to the open road.
Fiberglass and epoxy finished, so now the deck is sealed on both sides. Having used biscuits to glue the plywood sections together along with the fiberglass should create a strong deck. I decided to use Herculiner truck bed liner to seal the bottom of the deck. It will take at least 2 coats, but and hope to finish tomorrow night. Then I'll be able to flip the deck over and permanently attach to the trailer.
Flipped the deck over tonight and started on the raised deck and electrical conduit. I used 2" poplar boards as the strips to support the upper deck. These were attached with 2" Stainless steel screws. The conduit was positioned and holes were cut to accommodate the pipes, which will house the trailer wiring.
Wood support strips were placed around the routed A/C return, as well as the trenches for the 110V electrical wiring and 12V for the galley. I originally thought I would paint this, but realized that no on will ever see this anyway once the top deck is attached.
The aluminum strip at the back is extra support for the spare tire holder. Running the wires through the conduit will be the next step, as well as cutting insulation for the blank areas.
I decided to paint the interior of the raised deck to help keep everything sealed. Not sure why I picked brown, as no one will see it.
I'm running some of the electrical cabling through the raised deck. Click here to see the electrical thread.
Pink insulation was added to the gaps in the deck. I also used a rain gutter pipe as the air return for the A/C unit.
I may use spray foam to seal the gaps in the remainder of the deck, but I still have some electrical items to complete first.
The spare tire mount was installed on top of an aluminum strip to give additional support.
Using expandable spray foam, I sealed the remainder of the deck for insulation.
I used a hacksaw blade and a surfoam to remove the excess foam. Once the foam is level with the raised deck sides, then the top deck can be installed.
The top deck was installed, and wires pulled through the top, along with the air return.
Close up of the air return and wiring. Speaker and stereo remote, trailer light and brake wiring, 12V to Galley, and 110V to Galley.
The back part of the top deck also needed holes for the air return and wiring.
The top deck consists of 3 sheets of plywood, with the one piece in the middle being the smallest. Once I finished installing that last middle piece, I filled all the screw holes and sanded down the joints. I originally was going to use some flooring material on top of this layer, but decided that it was unnecessary as most of it would just be hidden underneath a Mattress anyway. I will paint it as the last step in the raised deck. The entire deck is very sturdy now, and a very solid base for the teardrop.r