How to Use the Rupes LHR21 Mark V Random Orbital Polisher

Quick answer

Start with a clean surface, use a medium-cut pad and compound, set speed to 4-5, and work in a crosshatch pattern with light pressure.

Step-by-step guide to using the Rupes LHR21 Mark V

1. 1. Prepare the surface and choose your pad: Wash and dry the panel thoroughly. Select a pad based on the level of correction needed: a medium-cut pad for moderate swirls or a finishing pad for light haze. Attach the pad to the PrecisionPro backing plate, centering it carefully. Common mistake: using a dirty or worn pad. Always start with a clean, conditioned pad.
2. 2. Apply compound to the pad, not the panel: Squeeze a dime-sized bead of compound onto the face of the pad. Spread it over a 2x2 foot area at low speed (2-3) before increasing speed. This prevents splatter and ensures even coverage. Checkpoint: if the compound dries out or powders, you are using too much product or working too long without refreshing.
3. 3. Set speed and begin polishing: Set the variable-speed dial to 4-5 for cutting or 3-4 for polishing. Hold the polisher flat against the surface with light to medium pressure (about 5-7 lbs). Move in a slow crosshatch pattern: left-right, then up-down, overlapping each pass by 50%. Common mistake: pressing too hard. The polisher's orbit does the work; heavy pressure stalls the pad and reduces cut.
4. 4. Work in sections and check your progress: Polish one 2x2 foot section for 3-4 passes before moving to the next. Wipe off residue with a microfiber towel and inspect under a work light. If swirls remain, repeat with a more aggressive pad or compound. Checkpoint: if you see holograms or micro-marring, switch to a finer pad and reduce speed.
5. 5. Finish with a polishing or wax step: After correction, swap to a finishing pad and a fine polish at speed 3-4 to refine the gloss. Follow with a sealant or wax for protection. Clean the pad after each use to maintain performance. Common mistake: skipping the finishing pass. The correction step leaves a haze that needs refinement for a mirror shine.

Product facts

• Rupes LHR21 Mark V Single Tool: Built around the advanced POLYSYNTHEC™ gear system and PrecisionPro backing plate, this 21 mm orbit polisher delivers smoother, more efficient power with reduced noise and vibration. The reduced vibration makes it easier to maintain consistent pressure and control during long correction sessions, leading to more uniform results.