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Thin Section Preparation:
Select a clean specimen - no oil from the natural environment or from rock saws,
- Cut specimen using a water-cooled saw to approximately 1"x2"x1/2" thick.
- Lap specimen using the large 12" diameter power lap wheel with 200 grit until all saw marks have been removed.
- Thoroughly wash specimen to remove any trace of cuttings and grit.
- Lap using 400 grit on a glass plate until all scratch marks from earlier lapping have been removed, and the sample looks absolutely flat in reflected light.
- Thoroughly wash and clean the specimen.
- Lap using 600 grit on a glass
plate - a different plate - not the one you just used.
- Thoroughly wash the specimen.
- Frost a clean glass slide on one side only using 400 grit.
- Wash the slide thoroughly
- Place specimen and glass slide in a clean plastic tray, place sample in the oven (set on the 3 setting) for at least overnight. The specimen must be absolutely dry.
- Mix a small amount of epoxy glue and mount the specimen to the frosted side of the slide.
- Allow the specimen to cure in the oven (same setting) for at least 6 hours.
- Clean the back of the slide with a razor blade to remove all glue.
- Place slide (with section) on the mounting arm of the Buehler thin section machine. Be certain that the chuck arm has been cleaned before mounting the slide using fresh water from the tap.
- Turn on the vacuum switch.
Vacuum must reach at least 20 pounds before you cut the sample.
If it does not reach 20, clean slide and chuck arm, then remount.
- Move chuck arm to the left by gently pushing the arm against spring tension, then lower the arm. Be sure that the saw is properly adjusted to give you a thin section when sawing. Turn on the saw, turn on the water, then slowly rotate sample into the diamond saw. Remove sample to check your setting.
- Gently guide the sample back against the saw blade, and allow gravity to move the sample through the cutting process.
- After sawing is complete, gently raise the arm, then allow the spring tension to move the arm over to the diamond grinding wheel.
- Gently lower the sample against the grinding wheel. Be sure that the sample does not touch the grinding wheel initially.
- Adjust micrometer setting two (2) counts each time you take a pass. Move arm
S l o w l y until sample is at about the correct thickness.
- Turn off the vacuum, the water, and the saw motor.
- Remove sample only after the vacuum is at a setting of less than 5 pounds.
- Final lap the sample to correct thickness using 600 grit on a clean glass plate.
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