CD Machine Polishing & Compound Selection 3 — Questions and Answers
Question 1: A rotary polisher set at 1,800 RPM is most analogous in actual pad speed to a DA polisher set at approximately:
- 3,000 OPM
- 6,000 OPM
- 9,000 OPM (Correct answer)
- 12,000 OPM
Correct answer: 9,000 OPM
Due to the DA polisher's orbital motion reducing effective cutting speed, approximately 9,000 OPM on a DA is needed to approximate the cutting action of 1,800 RPM on a rotary.
Question 2: What is 'jeweling' in the context of machine polishing?
- Applying a liquid crystal coating after polishing
- A final ultra-fine polishing step to maximize gloss and clarity (Correct answer)
- Adding metallic flake compounds to enhance paint depth
- Using a rotary polisher on glass surfaces
Correct answer: A final ultra-fine polishing step to maximize gloss and clarity
Jeweling refers to the final ultra-fine polishing stage using the least aggressive polish and pad to maximize surface clarity and gloss.
Question 3: When selecting between a 5-inch and a 6-inch backing plate for machine polishing, the 5-inch plate is preferred for:
- Large flat hood panels for maximum coverage
- Panels with complex curves and tight areas (Correct answer)
- Heavy oxidation removal on horizontal surfaces
- Applying base-coat touch-up paint
Correct answer: Panels with complex curves and tight areas
A smaller 5-inch backing plate offers better maneuverability on curved panels and tight contours, reducing the risk of uneven pressure and strike-through.
Question 4: Which condition indicates that a polishing pad needs to be replaced rather than cleaned?
- The pad has a slight yellow tint from polish residue
- The foam has compressed permanently and no longer returns to its original thickness (Correct answer)
- The pad shows minor surface glazing that rinses off
- The pad has absorbed a small amount of compound
Correct answer: The foam has compressed permanently and no longer returns to its original thickness
Permanent foam compression reduces pad effectiveness and can cause uneven polishing; a pad that doesn't spring back should be replaced.
Question 5: Why should a detailer avoid applying compound directly to the center of a polishing pad?
- The center of the pad generates the most heat and will burn the product
- Product applied only to the center distributes unevenly and may fling off at startup (Correct answer)
- Compound damages the pad's center mounting hardware
- The center is reserved for finishing polish only
Correct answer: Product applied only to the center distributes unevenly and may fling off at startup
Applying compound only to the center causes uneven distribution and increases the risk of product flinging off when the machine starts, so product should be applied in a cross or dot pattern near the edges.
Question 6: What technique helps prevent compound from drying out prematurely during a polishing session in hot or dry conditions?
- Increasing machine speed
- Adding water or quick detailer to thin the compound on the pad (Correct answer)
- Using a heavier compound with more filler
- Working larger sections at one time
Correct answer: Adding water or quick detailer to thin the compound on the pad
Misting the pad or work area with water or quick detailer prevents compound from drying and dusting, maintaining lubricity and cutting ability.
Question 7: A customer's black vehicle has heavy water spot etching below the clear coat. The MOST appropriate first step is:
- Apply a finishing polish immediately
- Use a clay bar to remove the spots
- Use a cutting compound with an aggressive pad to level the surface (Correct answer)
- Apply a water spot remover chemical only
Correct answer: Use a cutting compound with an aggressive pad to level the surface
Water spot etching that has penetrated below the surface requires mechanical cutting with an aggressive compound and pad to level the paint around the etch marks.
CD Machine Polishing & Compound Selection 3
A rotary polisher set at 1,800 RPM is most analogous in actual pad speed to a DA polisher set at approximately: