Flat Laps for Pumice
Pumice pre-polish is the stage between smoothing and final polish — it takes the grey haze off a smoothed glass surface and leaves it ready for cerium oxide. What you run the pumice on decides how fast that stage goes and how even the result is. These are the two laps built for it.
Synthetic felt pads — .050" thick
Optical-grade felt with a solid, unperforated face. The felt holds the pumice slurry evenly right across the disc, so the cut stays consistent edge to centre.
At .050" they match the thickness of resin diamond smoothing pads, so they drop into the same lap sequence without re-setting the machine.
- Four sizes: 8, 12, 18 and 24 inch
- Also excellent for facet work with cerium oxide
- Gentler, more controllable finish
MJ urethane laps
Extruded urethane carrying fine fibres that generate friction against the glass, with an open pore structure that holds the pumice in place.
Faster and more aggressive than felt — the choice for larger work and production runs.
- Two sizes: 24 inch (magnetic backed) and 30 inch
- Cuts the pre-polish stage down noticeably
- Mounts and swaps in seconds on a magnetic platen (24")
The full range
Synthetic Felt Polishing Pad — 8 Inch
8" · .050" thick · solid face
HG-HGF8-050
$19.60
Synthetic Felt Polishing Pad — 12 Inch
12" · .050" thick · solid face
HG-HGF12-050
$49.00
Synthetic Felt Polishing Pad — 18 Inch
18" · .050" thick · solid face
HG-HGF18-050
$120.54
Synthetic Felt Polishing Pad — 24 Inch
24" · .050" thick · solid face
HG-HGF24-050
$233.24
MJ Urethane Flat Lap — 24 Inch, Magnetic
24" · 15 mm · magnetic backing
HG-LAPIT-24-MJ
$293.02
MJ Urethane Flat Lap — 30 Inch
30" · 2-3/4" thick
HG-LAPIT-30-MJ
$476.28
Sizes and thickness at a glance
| Lap | Diameter | Thickness | Backing | Price |
|---|---|---|---|---|
| Synthetic felt | 8" | .050" | — | $19.60 |
| Synthetic felt | 12" | .050" | — | $49.00 |
| Synthetic felt | 18" | .050" | — | $120.54 |
| Synthetic felt | 24" | .050" | — | $233.24 |
| MJ urethane | 24" | 15 mm | Magnetic | $293.02 |
| MJ urethane | 30" | 2-3/4" | — | $476.28 |
Getting the best out of them
- Match the lap to your platen. Order the diameter your flat lap grinder is built for — an undersized lap wears unevenly at the rim.
- Keep the pumice wet and worked into the face. A dry lap glazes over and stops cutting; a properly charged one cuts steadily for a long session.
- Run pumice and cerium on separate laps. Cross-contamination is the single most common reason a final polish will not come clear.
- Rinse the lap down at the end of a session so the slurry does not set into the felt or the urethane pores.
- Step up, not around. Finish smoothing properly before pre-polish — pumice removes haze, it does not remove scratches.