3" x 24″ Cork Sanding Belt – 12 Pack | For Premium Glass Fabrication Finishing

The Makita 9924DB and the CR Laurence LD324 are the 3 x 24 portable sanders glass shops set up for edge work, and a shop that seams and refines edges on one of them polishes on it too. This ungritted cork belt is that polishing step: charged with cerium oxide slurry, it takes the fine matte left by a 400 to 800 grit silicon carbide belt to a clear polish, on the same sander, with no separate polishing machine.

We convert these belts in Anaheim, California from natural cork bonded to a cloth backing and pack them twelve to a box, the largest pack in our cork range for a portable size, because a 3 x 24 sander on an edging bench runs all day. Glass shops, stained glass studios, and stone and acrylic fabricators using the same sanders buy them.

• Ungritted natural cork on cloth: a carrier for cerium oxide or pumice, not an abrasive
• 3 x 24 size for the Makita 9924DB, CR Laurence LD324 and other 3 x 24 sanders
• Follows the 3 x 24 silicon carbide belt on the same sander after 400–800 grit
• Longer platen contact than a 3 x 21 for straighter polishing on long edges
• Twelve belts per pack for an edging bench that polishes every day
• Converted in Anaheim, California; free shipping on orders over $200

How does a cork belt turn a matte edge into a polished one?

Silicon carbide cuts. Every grit leaves scratches, and even the 800 grit pattern on glass reads as a uniform grey matte. Polishing needs a different mechanism: loose compound held against the glass by a carrier that is soft enough to conform and firm enough to press. Ungritted cork is that carrier. It has no grain of its own, cannot scratch, and its open structure holds slurry in the same way a felt or cork lap does on a bevelling machine.

Charged with cerium oxide the cork belt removes the fine matte and leaves the edge clear. Charged with pumice it gives a quicker, cheaper bright pre-polish that is often enough on edges that will be framed, or a first stage before a second cork belt with cerium. Run dry, or run without compound, it only warms the glass. The same belt polishes granite, quartz, solid surface and acrylic after a 400 grit pass with a fine polishing paste, and knife makers charge cork with a green stainless compound to pre-polish bevels after 600 to 800 grit.

Which compound should you use on a 3 x 24 cork belt?

• Cerium oxide: for a clear, optical polish on shower door, mirror, table top and shelf edges. Mix with water to a thin cream. Fastest after 600 or 800 grit.
• Pumice: for a bright pre-polish after 400 grit on edges that will be hidden in a channel or frame, or as the first of two cork stages.
• Fine polishing paste: for stone, quartz, solid surface and acrylic edges on the same sander.
• Green stainless compound: for steel and knife bevel pre-polish with the sander in a bench stand.

Compound is sold separately. With twelve belts in the box there is no reason to share one between compounds: mark each belt on the inside with the compound it carries. A pumice grain in a cerium belt scratches every edge polished after it.

Grit guide: the silicon carbide stages before the cork belt

The cork belt removes only the previous scratch pattern. On a 3 x 24 sander the whole sequence runs on one machine with a lever change between belts, so step through every grit.

Hold the finished edge to a light. Lines or haze mean the previous grit was not completed; go back one belt and repeat rather than spending more time on cork.

Which sanders take a 3 x 24 cork belt?

• Makita 9924DB: the 3 x 24 sander most glass shops run on the edging bench. Verified fit.
• CR Laurence LD324: the glass-industry 3 x 24 sander named on our matching silicon carbide listing.
• Other 3 x 24 belt sanders, portable or bench-mounted. Confirm the length in the manual; a 3 x 21 sander is three inches short and will not tension this belt.

This belt is the polishing partner to our 3 x 24 silicon carbide glass belt and mounts the same way: release the tension lever, slide the belt on, check the inside for a direction arrow, re-tension, start the sander clear of the work and set tracking so the belt runs centred on the front roller. Cork is thicker than a coated belt, so the lever feels firmer and tracking wants a re-check after the first minute. On a variable-speed sander use the low end for cork.

How to charge and run a cork belt on a 3 x 24 sander

1. Finish on silicon carbide at 400 grit or finer, 600 or 800 for the fastest cerium polish. Rinse or wipe the edge so no swarf reaches the cork.
2. Turn any water drip off. The LD324-type setup that drips water for the silicon carbide belts should be dry for cork; the slurry supplies the moisture.
3. Mix the slurry: cerium oxide or pumice and water to a thin cream in a squeeze bottle.
4. Charge the running belt with the sander held clear of the work at low speed until the whole cork face is damp and evenly coated. Keep slurry away from the motor vents.
5. Polish with light pressure. Start the sander before it meets the edge, keep it moving with the platen flat, and let the machine's weight do the work. The longer 3 x 24 platen helps keep a long edge straight.
6. Keep the cork damp, not wet. Add a squeeze of slurry as the face dries and the polish slows. Never let the belt run dry with compound caked on it.
7. Check against a light, then release the tension lever and store the belt flat or hanging. Do not fold a cork belt.

Use it for / don't use it for

Use it for

• Polishing seamed and refined glass edges on the same Makita 9924DB or LD324 used to grind them
• Shower door stiles, shelves, table tops and mirror edges on an edging bench
• Bevels and edges on stained glass and art glass pieces
• Granite, quartz, solid-surface and acrylic edges after 400 grit
• Knife bevel pre-polish with green compound, sander in a stand

Don't use it for

• Seaming, shaping or chip removal; the silicon carbide belt does that
• Anything coarser than a 400 grit scratch
• Running under a water drip, or running dry without compound
• 3 x 21 or 3 x 18 sanders

Specifications

Frequently asked questions

Related products and guides

• 3" x 24" Silicon Carbide Glass Fabrication Belts, 12 pack (grinding stages before cork)
• All glass fabrication abrasives (silicon carbide belts, cork belts and discs)
• 3" x 21" Cork Sanding Belt, 8 pack, for Makita 9903-class sanders
• 4" x 24" Cork Sanding Belt, 6 pack, for Makita 9403-class sanders
• Custom belt sizes, including cork, made to order in about 3 days