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  1. Log all the thin section billets into the thin section log and assign them a number.
    1. Label the billets with their corresponding number and orientation, if applicable, with a wax pencil. It is very important that these do not get mixed up. Also, write the assigned number on the sample bag and request form.
  2. Make a sample tray by cutting a wypall (heavy duty paper towel) in half. Place it on a metal tray and draw a grid on it. Write the numbers assigned to the billets on the grid (Fig. 1).
    1. It is helpful to draw a small picture of the billet and orientation arrow next to the number for later reference.
    2. The tray will help you to carry samples around the lab safely.

                            Figure 1



       a. All the rocks should fit loosely. Do not wedge them in.

                                                                                Figure 2

                                  Figure 3

  1. Put the rubber pad on top of the rocks (Fig. 3 and 4).
  2. Sponge pad next on top of the rubber pad (Fig. 3 and 4).
  3. Then metal stopper on the sponge pad (Fig. 3 and 4).
  4. With the weight on top of the stopper (Fig. 3 and 4).

                                  Figure                                          Figure 4

5. Turn on the abrasive drum by overriding it and make sure it is dripping properly.


14. When finished the flat side of the sample should reflect light and feel smooth to touch (Fig. 5). If any parts look dull or feel rough it may need more time on the lap wheel.

                                  Figure 5
(Logitech Thin Rock Section Production Manual)


  1. Use the metal flat plate and Aluminum oxide wet dry sandpaper (Fig. 6).
    1. Start with lowest grit and move to highest.
      1. 240 grit will flatten the sample, but will leave it scratched.
      2. 400 grit will help remove scratches left by the 240.
      3. 600 grit is the finest and will make the billet smooth for bonding.
  2. Hold the billet flat by applying equal pressure across the sample and move in a figure 8 motion on the paper (Fig. 6).
    1. Move the figure 8 slowly across the whole surface.
    2. Rotate the billet from time to time.

                                                                                             Figure 6

3. When finished, the flat side of the billet should reflect light and feel smooth to touch (Fig. 5). If any parts look dull or feels rough, it may need more time sanding.