Sidecar Windshield How-to
This page explains the steps I took to make a polycarbonate plastic windshield for my 1984 California Sidecar Co. Friendship I.
1. Remove and trace the old windshield on paper
2. Measure the tracing size and order the new plastic (mine was 27″ x 41″)
3. Trace the old windshield onto the new plastic.
4. Cut and trim the new piece
5. Drill, bend and pre mount the new windshield
6. Mark the bottom edge of the new windshield on the sidecar body
7. Apply a new foam seal (if a new one is desired)
8. Mount the windshield
9. Install the snaps for the soft-top
TRACE THE PATTERN
I took the snaps off the old plastic and laid it down on large piece of paper. As I slowly rocked the old shield from side-to-side I drew its outline. This gave me a flat pattern to measure so I would know how large a piece of plastic to order.
I paid $75 for a piece of 3/16″ (aprox. 7mm) thick polycarbonate plastic. I recommend using 1/8″ thick material. I’ve had problems with tiny cracks that have appeared on the outer radius of the shield. Bending the plastic to this radius without heat has proven to be too much stress. The local plastic shop sold me HYZOD a LEXAN equivalent made by Sheffield, a subsidiary of the Bayer (aspirin) Co. I also bought a roll of 3M foam tape that is normally used to make a seal between a pick-up truck topper and the sides of the bed.
To cut the plastic I traced the pattern of the shield directly onto the protective sheet covering the new plastic. I extended the pattern lines about 1/4″ all the way around prior to cutting to have a little room for error. I cut the shape with a fine toothed, saber saw and used a table top, electric disc sander to finish the edges. The plastic was a dream to work with.
I simply drilled the holes with the plastic on top of a piece of wood.
Pre mount the shield and trace the bottom edge onto the sidecar body with a pencil or china marker. Remove the shield and apply the foam seal with the bottom edge along this line.
Because the plastic wants to stay flat, three or four hands would be useful. I used a strong nylon twine and tied a bowstring between the second snap holes. This helped hold the plastic in a curve that allowed me to bolt the shield in place. I was worried about the string breaking. The plastic had a lot of tension on it and it would have really hurt (maybe injured) me if the string had broken.
DON’T OVER TIGHTEN!
Ideally the screw heads would just touch the plastic and stop. The problem is tension must be applied to pull the plastic down to the foam seal. This is not ideal. The stress on the holes causes stress cracks in the material. Drill the mounting screw holes large enough to allow for some movement.
- Regular polycarbonate plastic is very soft. It scratches extremely easily. It may be worth the extra cost to buy the polycarb with the hardness coating. Like they use on cycle windshields. The fellow that sold me the plastic said it was about twice the cost (i.e. $150 US in 2001).
- The trailing edge of the plastic is developing tiny cracks. I’m not sure why but my guess is the radius of the bed is a little too much for the plastic.
I was warned NOT to heat the plastic to make the bend because it would expand in uncontrollable directions. I would be tempted to try heat because of these tiny cracks.
trailing edge cracks
- The mounting holes are cracking on the inboard side of the sidecar only! I have no idea why they would develop cracks only on one side. Perhaps making the mounting holes a little larger and adding washers or rubber grommets would ease the stress on the material around these holes.
mounting hole cracks
A more experienced windshield maker may have the answer to some of these problems.
Someone mentioned that he would like to make your windshield taller. Perhaps you could make the trailing edge longer. You would have to figure out where to drill the holes and make a new soft top, but it should work.