Building A Fiberglass Trunk Lid (part 1)

This body did not come with any type of trunk lid or filler piece for the trunk.  At first I was going to make a mold off the body and then pull a piece from the mold and complete a trunk.  After looking at how much it would cost for the fiberglass, resin, bondo,sandpaper, time etc.  and knowing that I would probably never need the mold again, I decided to just make one from fiberglass and finish it on the car.  Doing it this way makes the deck lid a little heavier but saves a lot of time and money.  I could make one out of sheet metal, but I wanted to keep the entire car fiberglass.  I started by taking a piece of 22 ga. sheet metal and rough bent it over an oxygen bottle to get a basis curve to fit the body.  Then I bent a long strip at 90 degrees and pop riveted it to the top or forward edge so that it would sit on the edge of the body. Next I used several sheet rock (sheet metal) screws and screwed it along the edge and bottom to suck the metal close to the body contour. Next I covered the sheet metal with wax paper , taped it down and then applied 4 layers of 1 oz  fiberglass mat ( not shown).  This then forms the basis for the trunk and the rest of the process.

Now comes the fun part.  I made a pattern of the contour of the body and transferred it to a 2 x 4 and rounded the edges of the contour on both sides,  This will make 2 lefts and 2 right sides to form the inside lip of both the trunk and the body.  Cover the  2 x 4 with wax paper so that it fits tight and nice, tape it down good and use  some mold release or car paste wax.  Cover with three or four layers of 1 oz fiberglass mat.  Make two off one side and then reverse and make two off of the opposite side.

I also need a nice straight one for the front or top of the trunk lid.  Use a nice straight 2 x 4 , cover with wax paper and apply 3 or 4 layers of 1 oz. fiberglass mat.

This picture shows all five fiberglass pieces along with the 2 x 4 I used to make the side pieces.

Trim the pieces with a band saw or jig saw leaving at least an inch on both sides.  Do this with all five pieces.  Use some lacquer thinner to clean up any mold release or wax residue.  Take some 36 or 40 grit sand paper and rough up the outside surfaces to help insure a better bond and grip for the fiberglass bondo.

Now its time to put these pieces in place.  Take some 36 or 40 grit sandpaper and rough up the inner surfaces of the body and the inner surface of the trunk.  Mix up some fiberglass bondo and spread it along the surface to be bonded (mated).  I pre drilled two 1/4 inch holes and pre fitted each piece so that when the installation takes place,  the bolts will hold the pieces in place until cured.  When cured (kicked) remove the bolts, fill the hole and dress up /off any excess.  Fill in low spots rough sand and get ready for the next step in part 2.

Filling Wheel Wells

With the body flipped over, I went ahead and finished the rear roll pan by adding some fiberglass bondo and then finishing off with some ultra lite bondo.  This picture also shows the extent of the wheel cutout that I am going to fix next.

I took my flat table ,covered it with wax paper and then laid up 4 layers of 1 oz. fiberglass mat , let set up and then repeated the process and wound up with two flat pieces big enough to cover each of the openings.  I then sanded the area on the back side of the body with 40 grit sandpaper on a small hand electric sander and got all of the ridges and bumps out so that the flat pieces I just made would lay flat.  

         

Next I cut the flat pieces about two inches larger than the area to fill.  Using fiberglass bondo, I coated the inside around the opening and placed the flat pieces against the body and secured them in place with six sheet rock screws - into pre drilled holes.  Then I used a bondo spreader and smoothed out the fiberglass bondo on both sides and let set up.  This does two important things:  one ,it gives a great deal of strength  to the panel by overlapping- and two , it allows the blending of the back and the front to occur.  I could have cut the flat panel to fit the opening  and beveled both the body and the flat filler piece and then used mat on the back side and fiberglass bondo on the front and eliminated the  step in the front.  I have found that in this type of situation, that I would rather have the strength that overlapping gives than go the other route.  Not that it wouldn’t work, because it definitely would - I just wanted extra strength from the overlap.  I then blended the front with some fiberglass bondo to fill some of the lower spots and then finished off with ultra lite bondo.

Here you can see what the back side of the filler piece looks like after some extra fiberglass bondo has been spread out and tapered.  This give some extra strength and makes it look a little better.  I will build a flat panel from Luann plywood and cover it when I upholster the trunk area.  This shot also shows the back of the cockpit bulkhead and how I filled the seam with fiberglass bondo to secure it in place and make it more ridged.       

This body has a  4 inch body roll pan installed at the factory and it must have been done on a Monday or Friday because it definitely needed some extra work.  I used my electric hand sander and sanded the edges as smooth as possible where the top of the roll pan and the bottom of the body were laminated together , roughed up the gel coat on both sides and then coated the entire length with fiberglass bondo and smoothed it out.  After it set up, I again sanded the area and blended it as much as possible , filled in the places I missed or were low and then when they were cured, I used ultra lite bondo and finished blending the two together.  It actually came out quite nice.  

This picture shows the roll pan and the wheel well after the ultra lite bondo has been applied and sanded.  From this point, there is just a little detail work to be done, and then these areas will be ready for the first coat of urethane primer. 

Remodeling The Cockpit

Well after looking at the back of the cockpit on this roadster and realizing that I am a big guy, I decided to do some remodeling and increase the length by about four inches , this way I will sit further back and gain more room inside and wind up with a much more comfortable ride.  So here I go to build a better ride.

You can see how and where I cut the back of the cockpit and then I moved it back about four inches and laid it on top of the remaining piece and bonded it together with some fiberglass bondo.  This is really great stuff!  Whoever came up with it should be in the hot rod hall of fame.  if there is such a thing. 

Next I cut a piece of 1 x 2 inch piece of poplar and glued( bondo) it to the top sides of the body and clamped it in place.  Actually the cut piece of the body is not fiberglassed in place yet , but I wanted to show how it was cut and “glued “ down.  So I got a little ahead of myself but now it is hopefully a little clearer.

Here is a closeup of the 1x2 in place and ready for the removed fiberglass piece to be bondoed in place both on the back and on the front.

After It has set up, I took some small pieces of fiberglass matt and tied the ends to the body.  I used three layers of 1 oz matt to do this.  Then I used fiberglass bondo to finish shaping the contour so that it would blend in and flow.

This picture shows how nice the whole process came together and flowed out.

When you look at the rough finished product, it flows nicely, looks good, and the benefits from the added four inches will make this two hour remodel worth the effort.  When I get to the actual finishing of the body, I will use ultra light bondo and this will smooth everything out and get it ready for primer.