by Bert Smith
That's right, the CREATION of a headrest. With aerodynamics coming onto the scene more and more each year, the design and construction of your headrest is a vital part, and should not be rushed. Here is a method that has been used and proven to be successful the past few years.
With the driver in the car, determine the location and tilt of the helmet. This can be done by measuring the height of the helmet above the car, and the distance between the brim and the top of the cockpit cover (Figure 1).
With the driver out of the car, replace the helmet using the above measurements. Now measure how deep the back of the helmet drops into the car (Figure 2).
The next step is to build a small shelf to hold up the back of the helmet (Figure 3).
Wax the edge of the helmet on both sides, then put a lip of bondo on the car where the rivets of the helmet touch the car (Figure 4). Leave the helmet in place until the bondo is completely hardened, then carefully remove the helmet. The helmet should now slide in, and lock into place. It may be necessary to file and use more bondo to achieve a perfect fit.
Now wax the entire exterior of the helmet, and put it into place. Cut strips of fiberglass cloth, about eight or nine inches in length, and about two inches wide. Cover the back half of the helmet with resin, and lay the Strips over the helmet, extending onto the car body a few inches (Figure 5). Put several layers of cloth on the helmet, using plenty of resin. After the resin has set and becomes hard, carefully remove the helmet. You will now have a mold for the helmet to slip into a perfect fit. This mold adds a lot of strength to the headrest.
The ideal material to use to construct the actual headrest is a large piece of scrap Kodak photographic paper, that has been coated with resin. The resin coating allows the paper to form a smooth headrest with no wrinkles or folds. Form the paper over the helmet mold to desired shape (Figure 6). Fasten the paper to the car with a staple gun or small tacks.
The entire headrest is now ready for fiberglassing. Three or four layers of cloth, or one or two layers of fiberglass mat will give needed strength. After fiberglassing, some bondo may be required, but the paper usually eliminates the need for much.
I hope you find these tips helpful in creating your headrest.
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