Quick answer

Plastic shim stock is ideal for precision adjustments on bench mills and lathes where non-magnetic, non-conductive, and corrosion-resistant shims are needed. Choose individual sizes for easy cutting and a snug fit.

Why plastic shim stock over metal?

Metal shims can conduct electricity, rust, or interfere with magnetic chucks. Plastic shim stock eliminates these issues while still providing reliable thickness for fine adjustments. It is also easier to cut with scissors or a knife, saving time during setup.

Choosing the right shim stock sizes

Plastic shim stock is available in individual sizes, letting you pick exactly the thickness you need without buying a multi-pack. Common sizes range from 0.001 to 0.030 inches. For most mill and lathe adjustments, start with a few common thicknesses and stack them if needed.

How to use plastic shim stock for precision adjustments

  1. Measure the gap: Use a feeler gauge or caliper to determine the exact gap you need to fill. Write down the thickness required. Always measure twice; plastic shims can compress slightly, so aim for a thickness that is 0.001-0.002 inch thinner than the measured gap.
  2. Cut the shim to size: Place the plastic shim stock on a clean, flat surface. Use sharp scissors or a utility knife to cut a piece slightly larger than the contact area. Trim to fit precisely. Cutting too small leaves gaps; cutting too large can cause the shim to buckle. Test-fit before final installation.
  3. Install and verify: Insert the shim between the mating surfaces. Tighten fasteners gradually and evenly. Re-measure the alignment or gap to confirm the adjustment is correct. If the fit feels too tight, the shim may be too thick. Remove and try a thinner size rather than forcing it.

Product facts

  • Shim Stock, Plastic, Individual Sizes: Color coded shim is made from a high quality plastic material. Easy to cut and resists oil. The color coding helps you quickly identify thickness, and the oil resistance means it won't degrade in a lubricated machine environment.

    Shim Stock, Plastic, Individual Sizes

    Shim Stock, Plastic, Individual Sizes