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Fiberglass Resto
How to accurately measure and straighten a fiberglass body
Created by Dan BurrillWhen hunting for a resto project, great finds can usually be had at swap meets or from ads in newspapers. It's not uncommon to find a project car that someone decided was too difficult to restore or that they simply lost interest in. Such was the case with the 1923 T-Bucket roadster shown here. The fiberglass body had been widened and the nose had been lengthened for more legroom. Fiberglass has a tendency to slightly warp or twist when overexposed to the elements, or as it ages. This body seems guilty on all counts.
T-Square
This problem is not necessarily hard to correct. The first step is to determine the severity of the damage to the fiberglass. You'll need to take exact measurements of the body from top to bottom, right to left, front to rear, and diagonally across the top of the cockpit. Coupes and enclosed cockpit cars don't seem to be as affected by age and weather, as do convertibles and roadsters, probably because the rigid top gives the vehicle more overall support.
Fiberglass is fairly easy to work with, compared to metal, so usually with some elbow grease a fiberglass body can be straightened and restored. Unlike metal, fiberglass doesn't rust, and damaged pieces can be cut with a Sawzall and replaced to look like new. Many times, just using spacers or bolting the fiberglass body on the steel frame can straighten out warp or fit problems that may exist.
Straighten Up
After taking all measurements, remove the body from the frame (if it came with one). Next, set the body on a flat concrete floor or other flat working surface. Then attach two horizontal aluminum square rods to help with the measuring. Wooden 2x2s also work well for this. With a Corvette or a Cobra type of body, draw a line through the center of the headlights and the taillights and add two more horizontal rods for a real accurate evaluation. For this T-Bucket, only two rods and two levels are needed to get the required measurements.
For an area that needs to be repaired or built up, use DuraGlass or Bondo body filler. Clean, sand, and prep the area to be repaired or built up. Then mix the product with the tube of catalyst, and apply in thin layers. Allow each layer to fully dry between applications. Remember to always sand the previous application before applying the next. Once the body shape is evened out, simply apply primer and paint.
Step 2
Set one level on each rod to check the back and the front of the cab for warp. If there is minor warp, it may be corrected when the body is bolted to the frame. Serious warp may require additional metal bracing to be attached inside the body to bring the body back to standard.
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Step 3
This is what the rod and level should look like for the most accurate measurements.
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Step 4
Start with the left rear and record the measurement from the rod to the floor. Needless to say, the right side should be the same as the left. Plastic, nylon, or rubber spacers or DuraGlass can be used to raise the lower corner if one side or the other is lower. Rubber bushings also work well for this.
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Step 5
Measure the left front to the floor and check the measurement with the right front.
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Step 8
The tape tells us that the extension that was glassed into the front from the firewall to the cowl is off. The upper right side is almost one inch shorter than the left. The short spot turned out to be only in the upper right corner of the firewall and it was fixable with a fiberglass patch and DuraGlass.
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