** The information provided below details the issues relating to CS-10F wheels and the efforts Taber Industries undertook to correct them.  Should you have any questions regarding this information, please feel free to contact us at 716.694.4000.

Based on numerous customer requests, Taber® Industries recognized that our CS-10F abrasive wheels presented an opportunity for product enhancements and a chance to modernize the manufacturing process.  After investing years of research into this project, Taber engineers developed an improved CS-10F wheel that maintained abrasion rates equal to the old version based on Taber’s internal quality requirements. 

Improved CS-10F Wheel (Type II) – Introduced in October 2002.  The enhancements included:

• New ‘Easy Glide’ wheel hub
• Increased consistency
• Extended shelf life
• Less color transfer from wheel to sample
• Change in wheel hardness to match other Calibrase wheels

Unfortunately, shortly after the market release Taber began to receive customer calls that the improved wheels were providing lower haze values.

Reformulated CS-10F Wheel (Type III) – With a limited number of improved CS-10F wheels (Type II) shipped, Taber responded swiftly.  A slight adjustment was made to the wheel formulation (June 2003), and a reformulated Type III wheel was introduced to the marketplace.  A memo providing detailed information regarding the need for this reformulated CS-10F wheel was supplied to customers who purchased Type II wheels (July 2003).

Following the second release of the improved CS-10F wheel (Type III), customers began to report higher haze values.  For some materials, the difference was considered significant.  After reviewing viable options with key industry members, Taber Industries notified our CS-10F wheel customers that the Type III wheel could provide higher haze values than expected (October 2003).

The initial improved CS-10F wheels (Types II and III) were designed based on their wear characteristics.  For the reformulation efforts, an evolutionary model design was utilized that identified and examined all potential sources of variation with respect to haze measurement.   As an example, when studying wheel refacing and preparation the following issues were investigated:

Wheel Preparation

Other sources of variation that were investigated included instrument set-up; specimen conditioning / cleaning; evaluation techniques; material issues; operator influences and instrument calibration. 

The evolutionary model established multiple wheel formulations and enabled Taber Industries to focus our evaluations on the wheel candidates that were most promising.  After a number of iterations, a wheel candidate was selected and used for validation round robin testing.  This interlaboratory test concluded that, with the recommended test method changes mentioned below, the performance of the Type IV wheel candidate provided results comparable to historical values.  Type IV wheels were introduced in October 2004.  Note, although CS-10F’s were historically red, the color brown was selected to distinguish between the other types of CS-10F wheels.

During the reformulation efforts, it became apparent that some ‘inconsistencies’ in the test results could be attributed a number of other factors.

In many cases, operators were unaware that the Taber Abraser should be calibrated on a regular basis.  To educate customers, a marketing campaign was undertaken to remind people that the Taber Abraser is a precision test instrument and must be calibrated.  To determine if an abraser is out of specification between annual calibrations, the Calibration / Verification Kit was developed.

During discussions with operators, a number of ambiguities in the test procedures were identified.  A thorough review of ASTM D1044 and ANSI Z26.1 Test 17 was conducted to identify vague instructions that might affect repeatability and reproducibility.  All recommendations and changes were made public while the methods were being balloted and approved.  These included:

Wheel Refacing

To ensure that the abrading function of the wheels is maintained at a constant level, they should be refaced prior to each test.  The recommended procedure for standardizing the CS-10F wheels is to reface them for 25 cycles on the fine side of an ST-11 refacing stone.  The procedure is shown below:

1.)	Mount the wheels on their respective flange holders, taking care not to handle them by their abrasive surfaces.
2.)	Select the load to be used (500 g on each wheel) and affix it to the abraser.
3.)	Mount an ST-11 refacing stone on the turntable, fine side up, and secure using the nut.
4.)	Lower the vacuum nozzle and adjust its height to within 0.8 to 1.6 mm (1/32 to 1/16 in) of the refacing stone.  Set the vacuum suction force to 100.
5.)	Lower the arms so the wheels contact the surface of the ST-11 refacing stone.
6.)	Reface the wheels before abrading each specimen for 25 cycles.

NOTE 1: Do not brush or touch the surface of the wheels after they are refaced.
NOTE 2: New wheels or wheels trued using a diamond tool refacer, must first be broken in with 100 cycles on the fine side of the ST-11 refacing stone followed by a test on the material to be evaluated (of 500 cycles or less) with the results to be discarded.
NOTE 3: A thin fin of wheel material may form on the left hand edge of the wheel as the main body of the wheel wears down.  To remove, gently rub the edge of the wheel using your finger.  Avoid touching the running surface of the wheel.
NOTE 4: The maximum allowed time between refacing and testing should not exceed 2 minutes.
NOTE 5: The ST-11 refacing stone has a useful life of 10,000 cycles (approximately 400 refacings of 25 cycles), after which it should be replaced.

IMPORTANT: It has been observed that debris may adhere to the side of the CS-10F wheel and dislodge during testing. To eliminate this as a potential source of variation, Taber Industries recommends using a soft bristle, anti-static brush (e.g. Taber p/n 132616). After resurfacing the wheels on the ST-11 refacing stone, gently pass the brush along the side of the wheels to remove any loose particulate material. [August 1, 2007]

ST-11 Refacing Stone

The useful life of the ST-11 Refacing Stone has been defined at 10,000 cycles (approximately 400 refacings of 25 cycles).  To monitor usage, a label is now included on the bottom of the container this product is shipped in.  It is suggested that for each refacing, one box be checked until all boxes are full.  When full, the refacing stone should be discarded and replaced.

Vacuum Pick-Up Nozzle Changes

It was found that a ‘modified’ vacuum pick-up nozzle with enlarged openings removed the debris from the wear path more effectively when conducting haze testing.  The Haze Kit (part #132615) may be purchased from Taber Industries or a Taber distributor, which includes:  modified vacuum pick-up nozzle assembly, antistatic brush, and a 1/32” gage pin.  Alternatively, you may modify the vacuum pick-up nozzle openings yourself (it is strongly suggested that it be marked to differentiate it from standard vacuum nozzle).

NOTE: If your company utilizes the Taber Abraser for tests other than ASTM D1044 or ANSI Z26.1, you will need a second vacuum pick-up nozzle with the standard nozzle openings. 

Cleaning Procedure

Before testing, any protective masking material should be removed from the specimen.  If required, the specimen should be cleaned using a method recommended by the manufacturer.  After abrasion, use a soft bristle, anti-static brush (part # 132616, available through Taber Industries) to lightly brush off any debris adhered to the surface of the test specimen.  To remove any remaining particulate, clean the specimen following the manufacturers’ recommendation or, if none is specified, use an Isopropyl alcohol soaked lint free cloth to gently wipe both surfaces of the specimen.

To ensure repeatability and reproducibility, it is advised that you verify the test method being used is current and reflects the most up-to-date version.  All companies following ASTM D1044 should be using the test method released in 2005 (referenced as ASTM D1044-05).

Click here to view a Taber abrasion test on Exatec® automotive glazing products according to test method ASTM D1044 (video is courtesy of Exatec LLC).

There are a total of four different wheel formulations that have been referred to as Taber CS-10F.  These are commonly referred to as Type I, Type II, Type III or Type IV.  There are distinguishing features to each wheel for easy identification.

CS-10F (Type I)

• Old style wheel
• Red color
• Metal hub sleeve inserts
• Metallic label
• Hardness reference Shore A 72 ±5 (referenced incorrectly as Shore D in ASTM D1044)
• Lot number and expiration date are printed on side of wheel
• Last batch expiration date October 2003

CS-10F (Type II)

• 1st release of improved style wheel
• Pinkish-red color
• ‘Easy-Glide’ plastic hub
• New design label including print area for lot code and expiration date
• Identified by production lots that begin with the letter: P, R, S, T, W, X, Y
• May result in false low haze readings due to ‘residue’
• Last batch expiration date July 2005

CS-10F (Type III)

• 2nd release of improved style wheel
• Pink color
• ‘Easy-Glide’ plastic hub
• New design label including print area for lot code and expiration date
• Identified by production lots that begin with the letter: Z, AA, AB, AC . . . through AS
• May result in high haze readings
• Last batch expiration date December 2006

** Will be available for a limited time after the release of Type IV, as model CS-T3 (part# 132661)

CS-10F (Type IV)

• Reformulated CS-10F wheel
• Brown color
• ‘Easy-Glide’ plastic hub
• New design label including print area for lot code and expiration date
• Identified by production lots that begin with the letter: AT, AW, AX, AY, AZ, BA . . .