GRINDING WHEEL GUIDE –

FEATURING THE 4 1/2 x 1/2 x 7/8 GRINDING WHEEL – Type 27 – A24R

AA Abrasives 40100 – Grinding Wheel – T-27 - A24R

4 1/2x1/4x7/8, Grinding Wheel, T-27, Resin Bond, A24R, Metal

• Our most popular wheel

• For general purpose grinding

• Longer life for fewer wheel changes

AA Abrasives – 40100 – Grinding Wheel

A24R grain is designed for use on tougher metals where consistent stock removal and wheel life is important. Grinding wheels made with this grain have a longer life than other grinding wheels resulting in fewer wheel changes.

What does it mean? A24R: A=Aluminum Oxide, 24=Grit (Coarse), R=Medium Bond. See the Grinding Wheel Guide below.

Portable grinders with Type 27 depressed center wheels are a favorite combination among the power tools users for metal fabricating.  AA Abrasives – 40100 – Grinding Wheel – T-27 - A24R is recommended for structural steel metal and welds and most other ferrous metals on grinders such as Dynabrade 50303 or Metabo WE14-125VS.

Dynabrade 50303 Depressed Center Wheel Air Powered Grinder can be used for fast stock and weld removal-rust and scale removal and heavy duty deburring with a 4 ½” Type 27 depressed center wheel like the AA Abrasives 40100.

Metabo WE14-125VS Electronic Variable Speed Small Angle Grinder is an alternate grinder that can be used with a 4 ½” Type 27 depressed center wheel like the AA Abrasives 40100. The advantage to using a variable speed grinder is that when you switch from a grinding application to a surface finishing application you can lower the RPMs according to the product specifications. If you do not require a variable speed grinder, check out the Metabo W8-115 4 1/2" Angle Grinder.

GRINDING WHEEL GUIDE

The First series of letters indicates Grain Type; A=Aluminum Oxide (Used in Metal Applications) C=Silicon Carbide (Used for Masonry Applications) ZA= Alumina Zirconium used for (Stainless Steel and Ferrous Metal Applications) TA=Ceramic Treated Aluminum Oxide (Used for Metal Applications)

The Second series of letters indicates Grain Size or Grit; 8-24=Coarse, 30-60=Medium, 70-180=Fine and 220-Up=Hard. The Third series of letters indicates Bond Hardness; A-N=Soft, O-S=Medium and T-Z=Hard.

Wheel Types; Type 1=Flat Wheel for Cutting, Type 27=Depressed Center Wheel for Grinding and Cutting Applications, Type 28=Hat or Saucer Shaped for Grinding and Type 29=constructed with an upward angle built into the grinding section to provide full face contact for light stock removal and blending operations.
Type 28 and Type 29 wheels may only be used on the face and never on the periphery for cutting-off.

Note: Harder Wheels have a longer life where a softer wheel will cut faster.

Fine Grain=Long Life=Slower Cutting and Grinding.

Coarse Grain=Short Life=Fast Cutting or Grinding.

ABRASIVE PRODUCTS AVAILABLE AT AA ABRASIVES

AA Abrasives coated abrasives product categories include resin fiber sanding discs, trim kut discs, flap discs, PSA cloth discs, quick change mini sanding discs, PSA gold stearate rolled sanding discs, PSA blue film discs, Hook and loop gold stearate sanding discs, Hook and loop blue film discs, mounted flap wheels, unmounted flap wheels, straight cartridge rolls, full tapered cartridge rolls, no lap bands, abrasive shop rolls, sandpaper, cloth sanding sheets, sanding belts.

The three basic raw materials used in the manufacture of coated abrasive products:

1. Grain - a synthetic or natural abrasive
2. Bond - an adhesive that permanently bonds the backing to the abrasive
3. Backing - a backing that the abrasive is bonded to

To view any of these abrasives go to our coated abrasives page here AA Abrasives - Coated Abrasives

HOW TO USE RESIN BOND MOUNTED POINTS FOR GRINDING

Grinding applications require mounted points that have a perfect balance in terms of chip performance, intended surface finish and service life. In foundries and mold forming operations, the use of mounted points on straight grinders and flexible shafts is often the only method of getting to hard-to-reach parts on workpieces and simultaneously improving the surface.

For best mounted point performance, always run the mounted point at the maximum allowable speed according to AnSI B7.1. 

Resin Bond Mounted Points

“W” shapes are best used for offhand and precision grinding of medium to heavy stock . The most commonly used mounted points are the A-1 Resin Bond Mounted Points, A-3 Resin Bond Mounted Points and the W220 Resin Bond Mounted Points.  AA Abrasives resin bonded mounted points are made of premium aluminum oxide and designed for a high RPM die grinders. They are excellent for weld removal on hard to reach areas on metal and stainless steel. 

AA Abrasives resin bond mounted points are made from Aluminum Oxide, these mounted points come with a 1/4" shank.


In the video below, a W220 resin bond mounted point is used on a Dynabrade 52678 Straight Line Extension Die Grinder to finish 304 stainless steel racks.

If you are interested in A-1 or A-3 resin bond mounted points, please visit the appropriate link below - A-1 Mounted Points A-3 Mounted Points

Our online abrasives store is always open - Visit us at aaabrasives.com anytime.

Or call 1-800-888-1802 to speak to an abrasives specialist - M-F 9-4 EST

WHAT IS A STAINLESS STEEL WIRE END BRUSH?

Weiler Stainless Steel Wire End Brush

Stainless Steel Wire End Brushes are great for removing scale, slag, rust, paint, rubber or plastic flash removal.  They can be used for power tool operations on portable hand tools or drill presses for bores, pockets or corings. This is a versatile abrasive product for cleaning and finishing operations. The Weiler Brush 11113 has plastic rings which hold the wire straight so the tip does not bend when being used allowing for more aggressive action. The operator can remove each ring to expose fresh wire for longer life.

It is important to use good wire end brushes. Do not use damaged or rusted brushes. Wear eye protection and appropriate clothing and use machine guards when using stainless steel end brushes.

Industrial uses for stainless steel wire end brushes include: 

• Hardware;
• Manufacturing;
• Metal Finishing;
• Aerospace;
• Industrial Applications. 

WHAT IS A FLAP WHEEL?

MOUNTED FLAP WHEELS

A flap wheel is a versatile abrasive tool. Flap wheels are made of coated abrasive flaps arranged radially around a hub.  They are flexible and allow adaption to the shape of the workpiece. Flap wheels are suitable for applications such as deburring, finishing, polishing and cleaning. Mounted flap wheels are for use on die grinders, flexible shaft tools and high speed portable drills. Flap wheels produce a uniform, consistent finish on many different materials. Safe maximum RPM ratings are indicated on each flap wheel.

Flap Wheels are used in a wide variety of industries such as: aircraft manufacturing, engine manufacturing, assembly and tool rooms, furniture manufacturing, manufacturing of sporting goods, pots and pans manufacturing, tool and die manufacturing, nuclear power and power plant maintenance, manufacturing food and dairy equipment. The versatility of flap wheels make them an effective abrasive tool for many industrial abrasive applications. 

Video of 1"x1"x1/4" flap wheel-60 Grit - Item 10094 on an extension die grinder used for sanding and deburring inside stainless steel tubing.

AA Abrasives offers a full line of flap wheels, 1, 2 and 3 inch sizes available in either 1/4" Shank and 1/4-20 Threaded Shank with a Grit range from 40 to 320. These flap wheels mount to die grinders with a 1/4" collet.

Mounted Flap Wheel with 1/4" shank- Available in 1"- 2"- 3" diameters
Mounted Flap Wheel with 1/4-20 Threaded Shank - Available in 1" - 2" - 3" diameters

AA Abrasives offers a wide selection of Dynabrade extension die grinders suitable for this type of grinding. Choose from front or rear exhaust. Extension die grinders are available with either a 3" or 7 1/4" extension.

Dynabrade - 51302 - .5hp straight line die grinder - 20,000RPM - gearless, front exhaust - 1/4" collet
Dynabrade - 51306 - .5hp straight line die grinder - 20,000RPM - gearless, rear exhaust - 1/4" collet
Dynabrade - 53511 - .5hp straight line die grinder - 20,000RPM - 3" extension, rear exhaust - 1/4" collet
Dynabrade - 53502 - .5hp straight line die grinder - 20,000RPM - 7-1/4" Extension, rear exhaust - 1/4" collet

Unitized Wheels - AA Abrasives, Inc.

Unitized Wheels

AA Abrasives’ Unitized Wheels are designed to improve quality, increase productivity, and lower manufacturing costs. These multi finishing grinding wheels are excellent for cleaning, deburring, blending, finishing, and polishing. The structure of Unitized Wheels  minimizes heat build up to extend wheel life.  These wheels are less conforming than other preparation wheels to ensure a more consistent and uniform finish.

Unitized wheels are constructed by bonding and compressing layers of abrasives impregnated with non-woven nylon making it more aggressive than a Surface Prep Wheel. On a flat surface a unitized wheel will outlast the surface prep wheel making it a more efficient method for deburring, polishing and cleaning.

AA Abrasives, Inc. carries three types of Unitized Wheels.

2SF - is a softer less aggressive unitized wheel made with silicon carbide and is considered a fine.  This specific wheel is used in applications calling for a very fine non aggressive finish. Specifications: 4-1/2x7/8 #2SF Grey T-27 11,000 RPM  Item #33735.

Suggested Application for a 2SF unitized wheel - polishing mechanical parts such as blades, welds and threads or softer metals such as brass, aluminum, and copper. 

3SF - is considered a medium-soft silicon carbide fine grit. Specifications: 4-1/2x7/8 #3SF Grey T-27 11,000 RPM  Item #33736.

Suggested Application for a 3SF unitized wheel is cleaning heavy scale and oxidation on alloys, titanium and stainless.  

2AM - is considered a medium density with an aluminum oxide grain. This unitized wheel is the most aggressive and is recommended on heavier steels such as carbon and stainless steel. Specifications:  4-1/2x7/8 #2AM Tan T-27 11,000 RPM  Item #33737.

Suggested Application for the 2AM  unitized wheel - heavy blending or substantial burr marks on heavier steel. The 2AM unitized wheel will work on sharpened edges.

Use these unitized wheels on a variable speed grinder such as a Walter Big Buff 30-A-265 

or a Metabo 14-125VS Variable speed . You can decrease the RPM for duller finishes and polishes.

Our online abrasives store is always open - Visit us at aaabrasives.com anytime.

Or call 1-800-888-1802 to speak to an abrasives specialist - M-F 9-4 EST