1-1/8" x 21" Metalworking Sanding Belts, 20 PACK

The Makita 9031 belt file takes a 1-1/8" x 21" belt, and on metal that tool lives or dies by what is on it. These 1-1/8" x 21" metalworking belts give the 9031 and other belt files of the same size a proper metal grain: zirconia for carbon steel and iron, Zirconia+ (Grinding Aid) for stainless and aluminum where heat and loading are the problem, ceramic for hardened and tool steel under firm pressure, and Cloth A/O for the fine grits that finish the job.

We convert them in Anaheim, California on a Y-weight poly-cotton backing with heat-treated grain, so they stand up to the pressure of a narrow contact arm without stretching or shedding at the joint. Twenty belts of one grit per pack keeps a fabricator, millwright or auto-body shop from running out halfway through a weld seam.

• Exact 1-1/8" x 21" size for the Makita 9031 belt file and same-size electric and air belt files
• Ceramic, zirconia, Zirconia+ (Grinding Aid) and cloth aluminum oxide, one size, one listing
• 24–600 grit range: knock down a weld and grain the surface with the same tool
• Y-weight poly-cotton cloth built to outlast typical paper and light-cloth file belts
• 20 belts per pack; heavy grains can be run wet or dry
• Converted in Anaheim, California; free shipping on orders over $200

Which grain should you put on a belt file for each metal?

A belt file concentrates all its pressure on a strip barely over an inch wide, which is why it heats metal so fast. Choose the grain for the metal first and the pressure you can apply second.

• Zirconia: carbon and mild steel, cast iron, weld beads, general fabrication. It micro-fractures under load and stays sharp as long as you keep pressure on it. Offered in the coarse and medium grits, 24–120.
• Zirconia+ (Grinding Aid): zirconia with a grinding-aid top coat over the grinding aid already in the resin. The coating lubricates and cools the cut, which is exactly what a belt file needs on stainless steel, aluminum and titanium. It is the belt we recommend for TIG weld cleanup on stainless tube and handrail.
• Ceramic: the orange-red belt for hardened steel, tool steel, stainless and nickel alloys. It holds a near-constant cut rate for its whole life but only when fed firm, steady pressure. A 9031 has enough power to use it on the platen; on the nose wheel with light pressure it glazes.
• Cloth A/O: heat-treated aluminum oxide on the same poly-cotton cloth, forgiving at light pressure. All the 150 through 600 grit belts are aluminum oxide; they take out the coarse scratch on steel and are the right grain for brass, bronze and aluminum from start to finish.

Do not try to finish with zirconia or ceramic above 120 grit; the result is a bright scratch, not a finish. Step to Cloth A/O or a non-woven belt.

Grit guide for weld cleanup and deburring with a 1-1/8" x 21" belt

A typical stainless handrail sequence is 60 Zirconia+ (Grinding Aid) to level the weld, 120 to blend, then 220 and 320 Cloth A/O to match the mill grain. On aluminum keep to 80, 120, 220 Cloth A/O with the grease stick and never dwell.

What tools does a 1-1/8" x 21" belt fit?

• Makita 9031 belt file sander: the electric belt file this size is cut for, verified.
• Other electric belt files and air belt tools that list a 1-1/8" x 21" belt. Match both dimensions to the manual; a 1" x 21" belt will run on some 1-1/8" arms but wanders, and we stock the 1" width separately.
• Shop-built fixtures and small bench sanders adapted to this size for deburring small parts.

Mounting on a belt file: retract the arm, slip the belt over the drive and nose wheels, release the tension and jog the tool while adjusting the tracking knob until the belt runs centred. Check the inside of the belt for a direction arrow before you mount it; if one is printed, run the belt that way or the joint will lift. Unusual belt-file lengths can be made to order in about 3 days.

How to get the most out of it

1. Use the platen for leveling and the nose for reach. Grind a weld flush against the backed section of the arm; use the nose wheel only for inside corners and radii, where you cannot apply much pressure anyway.
2. Feed zirconia and ceramic pressure; feed aluminum oxide finesse. Self-sharpening grains need load to keep fracturing. If a zirconia or ceramic belt goes shiny and quiet, press harder or step down to a fresh belt; if aluminum oxide loads, ease off.
3. Never park the tool. A belt file blues stainless in a second or two of dwell. Work in long, overlapping strokes along the seam and let the belt speed do the cutting.
4. If your tool has speed control, turn it down for aluminum, brass and thin stainless. On a variable-speed belt file, slower speed plus a grease stick rubbed on the running belt keeps aluminum from packing the grain and stops thin stainless from warping.
5. Run wet on a wet-capable tool. The poly-cotton backing accepts coolant; a mist keeps titanium and stainless cool and the swarf off the belt. Most belt files run dry, which is fine on steel.
6. Clean loaded belts with a crepe belt eraser on the aluminum oxide grits, and switch to the grinding-aid belt if zirconia keeps loading.
7. Dust, sparks and storage. Collect steel dust in a metal-rated or wet collector, never a wood-dust bag. Wear eye and face protection. Store belts hanging or loosely rolled, dry, out of sunlight, and warm cold belts before use.

Use it for / don't use it for

Use it for

• Flushing and blending TIG and MIG welds on tube, handrail, roll cages and frames
• Deburring laser-cut, plasma-cut and punched steel and stainless parts
• Cleaning casting flash and parting lines on iron, steel and aluminum
• Reaching inside boxes, brackets and slots a grinder cannot enter
• Graining stainless and aluminum repairs to match the surrounding finish with the fine Cloth A/O grits
• Removing rust, scale and old coatings before welding or paint

Don't use it for

• Light-pressure work with ceramic; it glazes and heats the part instead of cutting
• Finishing with zirconia or ceramic above 120 grit; switch to Cloth A/O or non-woven
• A 1" x 21" tool or any belt file with a different belt length; measure first
• Sharing a dust collector between wood dust and steel sparks

Specifications

Frequently asked questions

Related products and guides

• 1" x 21" Metalworking Sanding Belts, 24 pack
• 1-1/8" x 21" Surface Conditioning Belts for satin blending on the 9031
• 1-1/8" x 21" Sanding Belts, 40 pack, for wood and general use
• Grease stick for sanding aluminum and non-ferrous metal
• Custom sanding belts made to order in about 3 days