3" x 10-11/16" Surface Conditioning Belts (Non-Woven), 5 PACK

Short, wide and stretch-resistant, this is the belt size that slips over a 3" expanding rubber drum on a Dynabrade-type pneumatic drum sander. A non-woven belt on an expanding drum is how foundries, die-cast shops and fabricators blend and deburr curved surfaces that a flat platen cannot reach: fillets, tube radii, casting parting lines, the inside of a bend.

These 3" x 10-11/16" surface conditioning belts are nylon web loaded with aluminum oxide on a reinforced scrim backing, sold five to a pack in one grade. Choose Coarse, Medium, Very Fine or Ultra Fine depending on whether you are stripping scale or putting a final satin on stainless.

• Sized for 3" wide expanding rubber drums with a 10-11/16" circumference (Dynabrade-type drum sanders)
• Scrim backing keeps the belt from stretching as the drum expands at speed
• Conformable web follows fillets, radii and castings without gouging
• Four grades: 40–60, 80–120, 180–240 and 320–400 grit scratch patterns
• Runs cool and resists loading on aluminum, stainless and titanium
• 5-pack of one grade; free shipping on orders over $200

Which grade should you choose for drum work?

Because an expanding drum puts the belt on a curved, slightly cushioned face, each grade behaves a little softer than the same web on a flat platen. Pick by the scratch you are removing.

• Coarse (40–60 grit scratch), brown: casting scale, forge scale, heavy oxidation and knocking down parting lines on aluminum and iron castings. The drum concentrates pressure on a narrow contact band, so this grade will cut a visible groove if you dwell.
• Medium (80–120 grit scratch), maroon: the general-purpose grade for blending weld toes on tube frames, deburring machined edges and prepping castings for paint or powder coat.
• Very Fine (180–240 grit scratch), blue: a uniform satin on stainless tube, railing fittings and food-equipment parts; the #4-style brushed look on curved work.
• Ultra Fine (320–400 grit scratch), grey: final finish on decorative stainless and aluminum, pre-polish before buffing, and cleaning heat tint off polished parts without dulling them.

Most drum-sander users keep Medium on the drum for daily work and switch to Very Fine for the final pass.

Grade guide for contour blending and deburring

Non-woven web refines a scratch pattern rather than removing stock. If the part still shows 60 grit lines, use a coated drum belt first, then this belt.

What does a 3 x 10-11/16 belt fit?

• Dynabrade-type expanding rubber drum sanders fitted with a 3" wide expander drum whose circumference is 10-11/16". This is the common drum belt size the old page of this product referred to, and it is the reason we stock it.
• Bench-mounted expanding drums on a grinder arbor or polishing lathe, where the drum expands under centrifugal force to grip the belt.
• Pneumatic drum sanders on a stand or in a fixture used for tube and railing fabrication.

Mounting: with the tool stopped, slide the belt over the drum. It should be snug but not forced; the rubber expands at speed and grips the belt from the inside, so a belt that is loose at rest is normal. Confirm the drum's width and circumference against 3" x 10-11/16" before ordering; expanding drums are made in several diameters and a belt one size off will either not fit or fly off. The web has no direction arrow and runs either way. If your drum is a different size, we cut custom belts in about 3 days.

How to get the most out of them

1. Bring the tool up to speed off the part. The drum has to expand before the belt is held firmly. Contacting the work before that happens can spin the belt on the drum and glaze the inside of the web.
2. Use a light touch. An expanding drum already concentrates pressure on a narrow contact strip. Let the web float over the surface; pressing harder just compresses the rubber and tears fibers.
3. Keep the drum moving along the contour. Sweep along a weld or a radius in overlapping passes. Dwelling in one spot with a drum leaves a bright band that is hard to blend out.
4. Follow a coated belt of matching grit. A Medium web after a 120 grit coated drum belt, or Very Fine after 180–220, gives a clean, even satin. Jumping from a coarse coated belt straight to a fine web leaves the deep scratches showing through.
5. Run a lubricant on aluminum. A light mist of water or cutting fluid keeps aluminum from smearing into the web. The belt is not harmed by moisture.
6. Clean and store. Blow the web out with compressed air and keep spare belts flat or hanging away from heat and sunlight. A belt eraser at low pressure will lift packed swarf from a loaded web.

Use it for / don't use it for

Use it for

• Blending weld toes and grinder marks on tube frames, handrails and stainless railing fittings
• Deburring and cleaning aluminum, zinc and iron castings on parting lines and fillets
• Satin finishing stainless food-equipment and pharmaceutical parts with curved surfaces
• Removing heat tint, light rust and oxidation from formed parts
• Prepping contoured parts for paint, powder coat or polishing
• Fiberglass, plastics and non-ferrous alloys where a coated belt would gouge

Don't use it for

• Heavy stock removal or grinding welds flush; use a coated drum belt first
• Flat panel finishing; a platen-backed belt sander or wide belt gives a straighter scratch
• Expanding drums of any other width or circumference
• A mirror finish; follow the Ultra Fine belt with buffing wheels and compound

Specifications

Frequently asked questions

Related products and guides

• All surface conditioning belts and discs
• 3-1/2" x 15-1/2" Surface Conditioning Belts for larger expanding drums
• 1-1/8" x 21" Surface Conditioning Belts for file sanders
• Rolloc Surface Conditioning Discs, 2" and 3"
• Custom belt sizes made to order in about 3 days