Mercury Floor Machines DC-21-1500 Burnisher – 21", 1500 RPM, 84 lbs
Mercury DC-21-1500: 21" Burnisher at 1500 RPM for Controlled Gloss
The DC-21-1500 runs a 21" pad at 1500 RPM — positioned between the 1170 RPM entry model and the 2000 RPM ultra-high-speed version. That mid-range speed delivers measurable gloss improvement on VCT and hardwood without the heat buildup or friction marks that a 2000 RPM machine can leave on softer finishes.
DC-21-1500 Motor and Pad Specifications
- Pad size: 21" — covers more square footage per pass than 19" or 20" models
- Speed: 1500 RPM — mid-range between the DC-21-1170 (1170 RPM) and DC-21-2000 (2000 RPM)
- Machine weight: 84 lbs — provides consistent downward pad pressure without operator effort
- Motor type: D.C. direct-current drive — sustained torque at rated speed under full pad load
- Compatible pads: White, tan, or natural fiber burnishing pads only; never use stripping or scrubbing pads at this speed
Where 1500 RPM Fits in Commercial Cleaning
A 1500 RPM burnisher suits facilities that need a visible shine without running the highest-heat machine on the floor. Grocery stores, retail chains, and office buildings with VCT or urethane-coated hardwood benefit from this speed range: enough friction to thermally bond the finish layer, not so much that the pad glazes or burns soft finishes. For facilities with a mix of floor types — some areas with older finish, others recently stripped and recoated — the 1500 RPM speed offers a workable middle ground that the 2000 RPM model does not. If the goal is dry-bright restoration on a single finish type with no variation, the DC-21-2000 is faster; if the floor is sensitive or the finish is thin, step down to the DC-21-1170.
Burnisher Pad Selection and Heat Cycle at 1500 RPM
At 1500 RPM, pad choice directly controls gloss output. White pads produce a harder, higher-gloss result because they generate more friction heat per pass. Tan pads are softer and leave a satin finish that masks minor scratches without fully filling them. Natural fiber pads (sisal or tampico blends) reduce heat transfer and work well on urethane or water-based finishes where thermoplastic bonding is less desirable. On each pass, allow the pad to complete the heat cycle — the finish should feel warm to the touch, not hot. Overlapping passes by 2–3 inches prevents lap marks. The 84 lb machine weight contributes approximately 0.6 lbs per square inch of pad pressure, which is consistent with manufacturer recommendations for 1500 RPM burnishing on commercial-grade finish.
| Specification | Value |
|---|---|
| Model | DC-21-1500 |
| Pad Size | 21" |
| Speed | 1500 RPM |
| Machine Weight | 84 lbs |
| Motor Type | D.C. Direct-Current Drive |
| Compatible Pads | White, Tan, Natural Fiber |