Common Manual: Working with Polycarbonate

Many of our kits utilize hard-coated polycarbonate for side windows, rear windows, headlight covers etc. Polycabontae can be cut and drilled using standard tools. If you want to do additional research note that Lexan is a General Electric (GE) tradename for their line of polycarbonate products. So while our kits don't use "Lexan" you can use the same fabrication techniques. However, note that Plexiglass is an acrylic and a different material.

General

• Keep the protective film attached until final installation to prevent scratches.
• Take care to keep heat generation from cutting, sanding or drilling to a minimum.
• Ensure that all oil, cutting oil, grease and other coatings are removed from blades, drill bits and fasteners. Certain oils and greases can cause environmental stress cracking.

Cutting

Polycarbonate can be cut with a hacksaw, jig saw or bandsaw. Use a clean, sharp metal-cutting blade with at least 10 teeth per inch. The most important consideration is to support and clamp the sheet to prevent chattering, particularly when using power tools. Allow the blade to perform the cutting; do not force the saw through the material. If possible adjust the saw speed so the blade is moving at approximately 12,000 strokes per minute.

When planning your cut you should leave room to sand the edge to the desired dimension. Radius any sharp inside corner or it will eventually crack.

Sanding

Once a cut has been made it should be finished with sandpaper. Start with 80 grit, and move to finer grits until you get to 400. That should leave a pretty smooth edge. Note that a belt sander (or any power sanding tool) should be used with care as it will quickly generate heat and many of the windows have curves in them which require more finesse than a flat sheet. Final sanding is typically best done with a long sanding board. Carefully work the edges to shape, frequently checking for fit. Remember, you can't un-sand the window! Take your time, and work carefully.

Drilling

Polycarbonate can with standard high-speed steel twist drills. The most important factor to consider when drilling polycarbonate is the heat generated during the actual process. In order to produce a clean, well-finished hole that is stress-free, the heat generated must be kept to an absolute minimum. By following a few basic guide-lines, clean, stress-free holes can easily be produced.

• Adequate support and clamping is required to reduce vibration and ensure a correctly sized hole.
• Holes should not be drilled closer to the edge of the sheet than 1-1.5 times the diameter of the hole.
• All holes must be larger than the bolt, screw or fixing to allow for thermal expansion and contraction.

Additional Resources

A excellent article on working with Lexan can be found here.