HOW TO READ A GRINDING WHEEL SPEC

The Measurement of a Grinding Wheel

Diameter of grinding wheel x Thickness of grinding wheel x size of arbor hole -

We will reference the AA Abrasives #60397 - 12x2x1-1/4 Pedestal Grinding Wheel T-1 Vitrified A36 - from our Vitrified Bonded Grinding Wheel Series.

12=Diameter x 2=Thickness x 1-1/4=Arbor Hole

*Note that the arbor hole can be bushed down meaning a bushing may be inserted in the arbor hole to reduce the size of the arbor hole.

Pedestal Grinding Wheel

What does the rest of the description mean after the size?

T-1 means the grinding wheel is flat. This is also referred to as a Type 1 Grinding Wheel or a straight toolroom wheel;

Vitrified is the bonding of grinding wheel;

A36 - A means it is an aluminum oxide grinding wheel and the 36 means the grinding wheel is composed of a medium grain size also known as grit.  See the grain size chart below.

A/O  also means aluminum oxide;

RPM is the Revolutions Per Minute or Maximum Operating Speed  - not all specifications will show this. The tool, the grinding wheel and application must be in agreement to ensure safe operation.

Grinding Wheel Specification Sheet

Grain Size/Grit:

Coarse: 8, 10, 12, 14, 18, 20, 24

Medium: 30, 36, 46, 54, 60

Fine: 80, 100, 120, 150, 180

Grade:

Soft: B, D, E, F, G, H

Med:  I, J, K, L, M, N

Hard: O, P, Q, R, S, T

Bond:

V- Vitrified

B- Resin

B2: Resin Bonded

BF: Reinforced Resin

Grain Types:

A- Dark Aluminum Oxide – Most common grain. Used for Heavy Duty General Purpose

AS3- 20% Ceramic Aluminum Oxide, 30% Pink Grain, 50% White Grain. Excellent for form and corner holding.

AZ- Blue Aluminum Oxide- Grinds fast with excellent cool cutting action and requires minimal dressing.

RA- Red Aluminum Oxide (Ruby)- Harder grain and sharper than PA & AZ wheels good for steels with high level chromium

PA- Pink Aluminum Oxide- General Purpose Grain that is tough but friable. Tool Room sharpening applications.

WA- White Aluminum Oxide- Highly friable grain for fast cool cutting. Good for light grinding on all steels particularly on tool and die steels.

GC- Green Silicon Carbide- very friable use for carbide grinding applications.

AA Abrasives carries its own line of Grinding Wheels.  We are also an authorized distributor of Norton Grinding Wheels. 

Visit our webstore to view our full line of abrasives and industrial power tools.

aaabrasives.com

Our webstore is open 24/7.

We are available by phone M-F 8:30 - 5 EST

1-800-888-1802

AA ABRASIVES WAFFLE WHEELS-FLEX-GRIND-FINISH-FGF WHEELS

AA Abrasives, Inc. introduces our newest wheel for grinding and finishing metals in one step. The AA Abrasives WaffleWheels-Flex-Grind-Finish-FGF-Wheels are reinforced resin bonded wheels with a flexible structure for multiple tasks.  The Waffle Wheel-Flex-Grind-Finish-FGF-Wheel is made of a white aluminum oxide grain for contaminate-free results and is recommended for metal, aluminum, non-ferrous metals, stainless and regular steel. 

     The face waffle pattern of the Waffle Wheels-Flex-Grind-Finish-FGF-Wheels is designed for cooler grinding and minimal material load up for a smooth finish. The flexibility of the waffle pattern on the face wheel is recommended on contours and is engineered to absorb vibrations to reduce operator fatigue. 

    

Some of the advantages of the Waffle Wheels-Flex-Grind-Finish-FGF-Wheel over a traditional grinding wheel are:

• They do not leave as deep scratches

• Operator has more control over taking down welds and metal removal while grinding

• Ability to have more control when getting close to Parent Metal

• A one step process prior to powder coat or painting over metal

Waffle Wheel-Flex-Grind-Finish-FGF Wheel

    The AA Abrasives Waffle Wheels-Flex-Grind-Finish-Wheels are used with a right angle grinder and are available in both a 7/8” and 5/8-11 arbor hole in a 4-1/2", 5" and 7” size in a T-27.

MetaboW8-115 Quick 600264420 as shown in video on electric power tool with AA Abrasives Waffle Wheels-Flex-Grind-Finish-FGF-Wheel 4-1/2x1/8x5/8-11 WA46-QBF#40750.

Recommended Dynabrade 52632 Air Grinder with AA Abrasives Waffle Wheels-Flex-Grind-Finish-FGF. Dynabrade 52632  for use with AA Abrasives Waffle Wheels-Flex-Grind-Finish-FGF-Wheel 4-1/2x1/8x5/8-11 WA46-QBF#40750.

Recommended Metabo W24-180 US606445760 electric power tool for use with AA Abrasives Waffle Wheels-Flex-Grind-Finish-FGF-Wheel 7 x 1/8 x 5/8-11 WA46-QBF #40754.

Recommended Dynabrade Air Grinder 50350 for use with AA Abrasives Waffle Wheels-Flex-Grind-Finish-FGF-Wheel 7 x 1/8 x 5/8-11 WA46-QBF #40754.

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

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.

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

How to Grind and Finish Stainless Steel with an AA Abrasives Dimple Wheel

AA Abrasives presents the Dimple Wheel. 

AA Abrasives AA-Flex Wheel aka The Dimple Wheel

The Dimple Wheel allows for one step grinding and finishing. These abrasive wheels are also known as the AA-Flex Wheel. They are constructed of aluminum oxide grains bonded to a strong, slightly flexible fiberglass reinforcing and have "dimples" on the grinding surface. AA-Flex wheels will remove stock much like a resin bond depressed center wheel and finish like a resin fiber disc. These flexible abrasive wheels are excellent for use on stainless steel and aluminum.

The Dimple Wheel is demonstrated here in a metal fabricating shop. The “Dimple” Wheel is used to grind and finish the surface of a stainless steel railing. The dimple wheel is used to create a smooth, uniform finish on stainless steel. This is a 4-1/2 x 1/8 x 7/8- A - Medium -Type 27 disc. The Dimple Wheel is used on a Metabo W8-115 angle grinder. 

Click here to view our full line of Dimple Wheels  - grinding and finishing in one step.

For additional technical information or information on any abrasive products, visit our website at aaabrasives.com or

Call 800-888-1802 to speak to an abrasives specialist at AA Abrasives.