RC shells create the overall look of your RC vehicle whether it's a plane, car or truck. With a switch of the shell you can change the look of your model from a plain painted streetcar to a professional looking ad-covered race car. Along with determining appearance of your vehicle, the shell absorbs much of the damage caused by regular use. New shells can begin to add up in costs though, so making your own can be a worthwhile project cost wise for the RC hobbyist. Doing so is achievable with a model of the shell you want and a homemade vacuum former. The results are a strong durable RC shell that meets or exceeds the quality of the manufactured product, at a discount in total price.
Measure and cut four 2-by-4 inch boards to a length of 26 inches with a table saw. Join the boards into a square containing a 24-inch opening by overlapping one end of a board over another and securing them at the overlapping section with two wood screws. Measure and cut a ½-inch sheet of MDF to create a 28 square-inch panel. Place the MDF over the 2-by-4 inch frame and join the two using wood screws through the panel into the boards beneath. Place a screw every four inches around the panel edge.
Drill a 1-inch hole through the centre of one of the 2-by-4 inch boards forming the side of the frame to hold the vacuum attachment.
Measure and cut the pegboard to create a second 28 square inch panel. Place it on the remaining frame opening and tape it to the 2-by-4s with duct tape around all of the seams between the panel and the boards. Place dust tape over all of the other seams in the frame as well.
Remove the bristles from a vacuum cleaner dusting brush hose attachment using a utility knife. Place a bead of epoxy onto the rim where the bristles attached and glue the attachment over the 1-inch hole in the side of the frame. Hold it in place for two minutes to allow the epoxy to take hold and secure the attachment. Place a bead of silicone caulk around the joint of the attachment and the frame to seal it tightly.
Create a second frame with a 24-inch opening using 1-by-4 inch boards cut 25 inches long. Join the frame with wood screws. Cut a sheet of Lexan to 25 square inches and staple it onto the new frame, with a staple placed through the plastic every ½ inch.
Create your RC body model. Sculpt the shape of the model you wish to create using wood or structural foam. You can use traditional woodworking tools to create the foam body. Due to the size of the former, your model must be less than 24 inches square. Height is less important due to the stretching qualities of the plastic.
Place the MDF/pegboard onto a flat surface with the peg side up. Attach the vacuum cleaner hose to the vacuum and then to the attachment on the frame.
Center the RC body model onto the pegboard.
Turn your oven on to broil. Place the second frame with the Lexan onto an oven rack, centred in the over. Watch the plastic. As it heats, it will begin to form rippling waves in its surface then go back to a level state. Remove the frame from the oven when it levels.
Place the frame onto the pegboard over the body model. Push the plastic straight down over the model if the model is greater than the four-inch height of the frame in order to avoid stretching one side of the body thinner than the other. Turn on the vacuum to apply suction through the pegboard against the plastic, pulling it down over the model. Continue to apply the suction as the plastic begins hardening. Turn off the vacuum, and remove the plastic frame. Pull the staples from the frame and pull away the Lexan. Cut the RC body from the plastic using the utility knife.
To create larger car bodies, increase the size of the frames. Push on areas of the plastic not forming tightly to the model with your fingertips to press the plastic against the model manually. Use lightly applied heat from a heat gun to heat any area of the plastic that cools too quickly to form properly around the model.
Wear heavy work gloves while creating the body to prevent burns.
Tips and warnings
- To create larger car bodies, increase the size of the frames.
- Push on areas of the plastic not forming tightly to the model with your fingertips to press the plastic against the model manually.
- Use lightly applied heat from a heat gun to heat any area of the plastic that cools too quickly to form properly around the model.
- Wear heavy work gloves while creating the body to prevent burns.