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Polishing and buffing: Theory and practice
Polishing and Buffing: Theory and Practice by Alexander Dickman, Jr. JacksonLea, a Unit of Jason Inc., Waterbury, Conn.
M
echanical finishing refers to an operation that alters the surface of a substrate by mechanical means, such as polishing or buffing. Polishing plays a vital role in the development of a quality product. The term polishing is not to be confused with buffing. The definition of polishing is the surface enhancement by means of metal removal, and is generally done by an abrasive belt, grinding wheel, setup wheel, or other abrasive media. A definite coarse line pattern remains after such a #polishing operation. This polishing effect removes large amounts of metal from a particular surface. Polishing refers to an abrading operation that follows grinding and precedes buffing. The two main reasons for polishing are to remove considerable amounts of materials to smooth a particular surface. This operation is usually followed by buffing to refine the surface. Buffing is the processing of a metal surface to give a specific or desired finish. The range is from semibright to mirror bright or high luster. Buffing is the processing of a metal surface to give a specific or desired finish. Depending upon the desired finish, buffing has four basic categories. These categories are (1) satin finishing-producing a satin or directional lined finish; (2) cutdown bufing-producing an initial smoothness; (3) cut and color buflng-producing an intermediate luster; (4) luster bufing (color buffing) for the high reflectivity or mirror finish.
TYPES OF BUFFING COMPOUND COMPOSITIONS Greaseless compound is used to produce a satin finish or a directional lined finish. Greaseless compound contains water, glue, and abrasive. As the name implies, it retains the abrasive on the buffing wheel in a grease-free environment, thus, leaving the surface of the finished part clean and free of the residue normally left when using other 34
types of compounds (which will be described later). The principal uses of greaseless compound are for satin finishing or flexible deburring. Generally, the abrasive contained in such compounds is silicon carbide or fused aluminum oxide. Grades are available in abrasive sizing from 80 grit or finer depending upon the degree of dullness required on a particular base metal. Silicon carbide abrasive are used for the finishing of stainless steel and aluminum. Aluminum oxide grades are used for brass and other nonferrous metals, as well as for carbon steel, prior to plating. To produce a finer satin finish on nonferrous materials, fine emery and hard silica are used. For Butler finishes on silver plate and sterling, fine buffing powders of unfused aluminum oxide and soft silicon are used. Greaseless is applied to a revolving buff by frictional transfer. The buff speed is 4,000-6,000 surface feet per minute (sfm). The material melts on the cotton buff, adheres to the peripheral surface, and dries in a short period of time. This produces a dry abrasive coated wheel with a flexible surface. The buffing wheels on which greaseless can be applied are sewed muslin buffs, pocketed buffs, full disk loose buffs, and string wheels. The coarser the abrasive particle, the duller the satin finish. The finer the abrasive particle, the brighter will be the satin finish produced, which is caused by the finer scratch lines. BAR COMPOUNDS Binder Bar compounds contain two types of ingredients, binder and abrasive. The binder can consist of one or more materials taken from animal or vegetable fats, as well as petroleum and similarly derived products. Animal fats are such materials as fatty acids, tallow, and glyceride. Waxes can be from vegetable-, insect-, or petroleum-based products. Petroleum-based or vegetablebased oils also may be used. The animal and vegetable materials are 0 Copyright Elsevier Science Inc.
more saponifiable. When combined with alkali, they will produce a watersoluble soap. The petroleum mineral oils and waxes are unsaponifiable materials and, therefore, might create subsequent cleaning problems. Each ingredient is added to the binder to transmit a specific effect to the bar, such a lubricity, degree of hardness, or improved adherence to a buffing wheel. A binder also controls the amount of frictional heat that can be developed on a surface. This is called slip. Abrasive In bar compounds, the second type of ingredient is the abrasive. There is a wide range of abrasive used in buffing compounds, a few of which are described here. Aluminum Oxide and Other Powders Aluminum oxide powders, fused and unfused, are the abrasive most commonly used in the cut buffing of hard metals, i.e., stainless and steel. Tripoli an&or silica are commonly used for cut buffing of soft metals, i.e., brass, aluminum, and zinc. Chrome oxide is used to achieve the highest reflectivity (color) on stainless steel, and chromium and nickel plate. To achieve a high reflectivity (color) on brass, gold, copper, and silver, iron oxide is generally used. Aluminum oxide is chemically represented as A&O,. The unfused aluminum oxide is white. This is manufactured from bauxite or hydrated aluminum oxide by heating at elevated temperatures. This heating process is called calcination, thus giving the abrasive the common name, calcined alumina. The higher the calcination temperature, the more water of hydration is driven off and the harder the crystalline material becomes. When the calcined temperature is about 95O”C, the product produced is a soft alumina having a porous structure. This type of abrasive is used for luster or color buffing. When the calcined temperature is about 1,25o”C, a harder alumina is produced. METAL FINISHING
??
DECEMBER
1995
This type of abrasive is used for cutting. Soft aluminas are used to produce luster or a higher reflectivity on all metals, both ferrous and nonferrous. The harder aluminas will cut and remove more metal from the surface of castings or extrusions of aluminum, brass, and other metals. When alumina is heated to 1,85O”C, fused A&O, is produced. This material is made in an electric furnace at approximately 2,OOOC. Bauxite, when mixed with alumina and other oxide materials, produces a specific crystalline structure whose hardness can be varied to meet specified physical properties. This fused mass is then cooled and crushed. In the crushing process, the material is ground, screened to the appropriate size, treated magnetically, and acid washed. It is then rescreened to its final classification (grit sizing). The difference between fused aluminum oxide and calcined alumina is that the fused oxide is of a crystalline structure that is much harder than that of the calcined alumina. Fused alumina oxide is used mainly on abrasive belts or setup wheels for polishing. As for buffing, fused aluminum oxide is used for cutting down ferrous metals. The abrasive sizing is generally from 60 grit to -325 grit for buffing compounds. Tripoli Tripoli is considered to be microcrystalline silica, which is naturally made. It is highly suitable for buffing of aluminum, brass, copper, and zinc die cast or other white metals. Tripoli and silica can be used as cutting abrasives or so-called cut and color abrasives for nonferrous metals. Tripoli should not be classified as an amorphous silica, but is microcrystalline in nature. Crystalline silica may cause delayed lung injury for people exposed to it over a long period of time. Users of products containing these abrasives should be aware of this possibility and provide adequate ventilation and masks to those who are exposed. Silicon Carbide The chemical symbol for silicon carbide is Sic. Silicon carbide is of a crystalline structure that is harder than fused aluminum oxide. It is formed by mixing coke and silica in an electric furnace at approximately 1,900-2,400C. The material is cooled, ground, and then screened to the required grit size in a METAL
FINISHING
??
DECEMBER
1995
Table I. Relative Hardness of Abrasives Abrasive Type
Chemicalsymbol
Aluminum oxide (fused) Aluminum oxide (calcined) Tripoli-silica Silicon carbide Iron oxide (red rouge) Chrome oxide (green rouge)
fbfd,Scale 8-9+ a9+
Al& Al& Si02 SIC Fe& CrJ4
process similar to that of fused aluminum oxide. The crystalline structure of Sic is a hexagon-type structure. Red Rouge The chemical formula for rouge is Fe,O,; it is also called jeweler’s rouge. Its purity is 99% ferric oxide. The crystalline structure of ferric oxide is spherical. Rouge is mainly used on precious metals to give an exceptional high luster. Green Rouge The chemical formula for chrome green oxide is Cr,O,. The hardness of chrome oxide is a 9 on the Moh scale as opposed to iron oxide, which is 6, and is used to produce an exceptional luster or color on ferrous, as well as nonferrous, metals. These abrasives are a small percentage of the materials available to give a specific finish required on a particular substrate. The relative hardness of each is shown in Table I. BUFFING WHEEL SPEEDS Although the wheel speeds for buffing with grease bars will vary greatly from job to job and operator to operator, the figures in Table II in surface feet per minute will serve as a guide for hand-buffing operations. Buffing wheel speeds for automatic operation may vary with the design of the machine and the contact of the work to the wheel. They can, therefore, be more definitely fixed without depending
9’6 6 8-9
upon the physical ability of the hand buffer to maintain the correct position and pressure against the wheel. LIQUID SPRAY BUFFING COMPOSlllONS Liquid spray buffing compositions have largely replaced bar buffing compositions on automatic buffing machines. Unlike the bar compounds previously discussed, the liquid buffing compound is a water-based product. The liquid buffing compound has three main constituents: water, binder, and abrasive. Water is used as the vehicle to transport the binder and abrasive to a buffing wheel through a spray system. The water and binder are reacted to form an oil/water emulsion. In this emulsion, the abrasive particulars are suspended and could be thought of as particles coated with a binder material. The emulsifying materials act as a device to hold the oil-soluble molecules onto the water molecules. Keep in mind that the abrasives are the same as used in bar compounds. The larger the abrasive particle, the less surface area present when compared with the weight of that particle. Surface area and density play an important role in the suspension of any liquid emulsion. Stability is the ability to keep the abrasive particle in suspension. When the abrasive particles tend to fall out of suspension, their weight factor is greater than the ability of the emulsified material to maintain stability. Viscosity, therefore, plays an important role in a suspension.
Table II. Suggested Wheel Speeds for Hand-Buffing Operations A&al Carbon and stainless steel Brass Nickel Aluminum Zinc and other soft metals Chromium
Cutfing Down (sfm)
Luster Suffhg (sfm)
8,000-9,000 6,000-9,000 6,OOC-9,000 6,00&9,000 5,000-8,000 7,000-8.000
7,000-9,000 6,OOO-9,000 6,00&8,000 6,000-7,000 6,000-7,OOU
35
hatever vour mass finishing requirements - in ’ quality, time cycles, operating v procedures and bottom line Washington Mills has a ceramic media in the right composition, density, shape and size to match... perfectly! Since 1868, our media has been evolving with the changing needs of industries like yours. Offering new choices for new products; and ever-superior results Washington Milk - World’s largest manufacturer of standard abrasive grains & specialty electrominerals as well as Boron Carbide.
on everything from golf clubs to 0 parts, jewelry to jet engine es to surgical instruments... and you name it! With Washington Mills, you take no chances. Quality, performance, consistency and durability are ALWAYS there. Plus service, expertise and experience unrivalled in the industry - from a pioneer and world leader. WASHINGTON Ceramics
MILLS Corporation
20 North Main Street North Grafton, Massachusetts 01536 Telephone: 508 839-6511 Fax: 508 839-7675 Telex: 6711292
of equilibrium for a defined period and at a constant temperature. A viscometer is used with a specific spindle. This reading, multiplied by a factor, will give a viscosity reading in centipoise. A plus or minus of 25% deviation is normal. The control of viscosity of a compound is somewhat difficult. Variations in raw materials or the method of blending are two reasons for viscosity changes. Viscosity is an arbitrary measurement. Liquid compounds are supplied to the spray guns by means of either airpressure feed tanks or high- and/or low-pressure drum pumping systems. The spray system needs to be designed to allow the liquid buffing compound to penetrate the air boundary of the rotating buff wheel and allow the compound to adhere to the wheel. Liquid abrasive compounds offer so many recognized advantages that their use is now accepted by the finishing industry as standard procedure for high-production buffing.
SUMMARY There are many other aspects of buffing and polishing than these briefly discussed here. Though this very important contributor to the metal-finishing industry is still a great deal more an art than a science, basic engineering principles can be applied. With the proper melding of buff and compound, applied in a controlled fashion, optimum finish and maximum economy can be achieved.
Circle 064 on reader information card
Biography The flow characteristics of a liquid buffing compound are controlled generally by the viscosity of that compound, as well as its degree of slip. The viscosity stability of any emulsion is established by its thixotropic nature, which means the viscosity becomes lighter in direct proportion to the amount of shear to which the compound is subjected. As the degree of slip is increased, the flow characteristics of the compound will also increase in direct proportion to the resultant change in slip or the resultant change in the coefftcient of friction. 36
The gel-type property of an emulsion is broken down by the action of the pump, thus producing viscosity changes. The changes are determined by the amount of shearing action of the pump and by the length of time. This breakdown is necessary to allow the transfer of the bufftng compound from the pump to the spray gun, which many times requires a significant distance. The viscosity of a liquid compound is measured under a constant set of conditions. To measure viscosity, a representative sample from a batch is needed. This sample must be in a state
Alexander Dickman, Jr. is Operation/ Technical Manager of Abrasive Products for JacksonLea, A Unit of Jason Inc., Waterbury, Connecticut. He has an A.D. in chemical engineering from Waterbury State Technical College and a B.S. in chemistry, with a minor in physics, from Southern Connecticut State University. He has been involved in the metal-finishing field since MF 1980.
METAL FINISHING . DECEMBER 1995
M
echanical finishing refers to an operation that alters the surface of a substrate by mechanical means, such as polishing or buffing. Polishing plays a vital role in the development of a quality product. The term polishing is not to be confused with buffing. The definition of polishing is the surface enhancement by means of metal removal, and is generally done by an abrasive belt, grinding wheel, setup wheel, or other abrasive media. A definite coarse line pattern remains after such a #polishing operation. This polishing effect removes large amounts of metal from a particular surface. Polishing refers to an abrading operation that follows grinding and precedes buffing. The two main reasons for polishing are to remove considerable amounts of materials to smooth a particular surface. This operation is usually followed by buffing to refine the surface. Buffing is the processing of a metal surface to give a specific or desired finish. The range is from semibright to mirror bright or high luster. Buffing is the processing of a metal surface to give a specific or desired finish. Depending upon the desired finish, buffing has four basic categories. These categories are (1) satin finishing-producing a satin or directional lined finish; (2) cutdown bufing-producing an initial smoothness; (3) cut and color buflng-producing an intermediate luster; (4) luster bufing (color buffing) for the high reflectivity or mirror finish.
TYPES OF BUFFING COMPOUND COMPOSITIONS Greaseless compound is used to produce a satin finish or a directional lined finish. Greaseless compound contains water, glue, and abrasive. As the name implies, it retains the abrasive on the buffing wheel in a grease-free environment, thus, leaving the surface of the finished part clean and free of the residue normally left when using other 34
types of compounds (which will be described later). The principal uses of greaseless compound are for satin finishing or flexible deburring. Generally, the abrasive contained in such compounds is silicon carbide or fused aluminum oxide. Grades are available in abrasive sizing from 80 grit or finer depending upon the degree of dullness required on a particular base metal. Silicon carbide abrasive are used for the finishing of stainless steel and aluminum. Aluminum oxide grades are used for brass and other nonferrous metals, as well as for carbon steel, prior to plating. To produce a finer satin finish on nonferrous materials, fine emery and hard silica are used. For Butler finishes on silver plate and sterling, fine buffing powders of unfused aluminum oxide and soft silicon are used. Greaseless is applied to a revolving buff by frictional transfer. The buff speed is 4,000-6,000 surface feet per minute (sfm). The material melts on the cotton buff, adheres to the peripheral surface, and dries in a short period of time. This produces a dry abrasive coated wheel with a flexible surface. The buffing wheels on which greaseless can be applied are sewed muslin buffs, pocketed buffs, full disk loose buffs, and string wheels. The coarser the abrasive particle, the duller the satin finish. The finer the abrasive particle, the brighter will be the satin finish produced, which is caused by the finer scratch lines. BAR COMPOUNDS Binder Bar compounds contain two types of ingredients, binder and abrasive. The binder can consist of one or more materials taken from animal or vegetable fats, as well as petroleum and similarly derived products. Animal fats are such materials as fatty acids, tallow, and glyceride. Waxes can be from vegetable-, insect-, or petroleum-based products. Petroleum-based or vegetablebased oils also may be used. The animal and vegetable materials are 0 Copyright Elsevier Science Inc.
more saponifiable. When combined with alkali, they will produce a watersoluble soap. The petroleum mineral oils and waxes are unsaponifiable materials and, therefore, might create subsequent cleaning problems. Each ingredient is added to the binder to transmit a specific effect to the bar, such a lubricity, degree of hardness, or improved adherence to a buffing wheel. A binder also controls the amount of frictional heat that can be developed on a surface. This is called slip. Abrasive In bar compounds, the second type of ingredient is the abrasive. There is a wide range of abrasive used in buffing compounds, a few of which are described here. Aluminum Oxide and Other Powders Aluminum oxide powders, fused and unfused, are the abrasive most commonly used in the cut buffing of hard metals, i.e., stainless and steel. Tripoli an&or silica are commonly used for cut buffing of soft metals, i.e., brass, aluminum, and zinc. Chrome oxide is used to achieve the highest reflectivity (color) on stainless steel, and chromium and nickel plate. To achieve a high reflectivity (color) on brass, gold, copper, and silver, iron oxide is generally used. Aluminum oxide is chemically represented as A&O,. The unfused aluminum oxide is white. This is manufactured from bauxite or hydrated aluminum oxide by heating at elevated temperatures. This heating process is called calcination, thus giving the abrasive the common name, calcined alumina. The higher the calcination temperature, the more water of hydration is driven off and the harder the crystalline material becomes. When the calcined temperature is about 95O”C, the product produced is a soft alumina having a porous structure. This type of abrasive is used for luster or color buffing. When the calcined temperature is about 1,25o”C, a harder alumina is produced. METAL FINISHING
??
DECEMBER
1995
This type of abrasive is used for cutting. Soft aluminas are used to produce luster or a higher reflectivity on all metals, both ferrous and nonferrous. The harder aluminas will cut and remove more metal from the surface of castings or extrusions of aluminum, brass, and other metals. When alumina is heated to 1,85O”C, fused A&O, is produced. This material is made in an electric furnace at approximately 2,OOOC. Bauxite, when mixed with alumina and other oxide materials, produces a specific crystalline structure whose hardness can be varied to meet specified physical properties. This fused mass is then cooled and crushed. In the crushing process, the material is ground, screened to the appropriate size, treated magnetically, and acid washed. It is then rescreened to its final classification (grit sizing). The difference between fused aluminum oxide and calcined alumina is that the fused oxide is of a crystalline structure that is much harder than that of the calcined alumina. Fused alumina oxide is used mainly on abrasive belts or setup wheels for polishing. As for buffing, fused aluminum oxide is used for cutting down ferrous metals. The abrasive sizing is generally from 60 grit to -325 grit for buffing compounds. Tripoli Tripoli is considered to be microcrystalline silica, which is naturally made. It is highly suitable for buffing of aluminum, brass, copper, and zinc die cast or other white metals. Tripoli and silica can be used as cutting abrasives or so-called cut and color abrasives for nonferrous metals. Tripoli should not be classified as an amorphous silica, but is microcrystalline in nature. Crystalline silica may cause delayed lung injury for people exposed to it over a long period of time. Users of products containing these abrasives should be aware of this possibility and provide adequate ventilation and masks to those who are exposed. Silicon Carbide The chemical symbol for silicon carbide is Sic. Silicon carbide is of a crystalline structure that is harder than fused aluminum oxide. It is formed by mixing coke and silica in an electric furnace at approximately 1,900-2,400C. The material is cooled, ground, and then screened to the required grit size in a METAL
FINISHING
??
DECEMBER
1995
Table I. Relative Hardness of Abrasives Abrasive Type
Chemicalsymbol
Aluminum oxide (fused) Aluminum oxide (calcined) Tripoli-silica Silicon carbide Iron oxide (red rouge) Chrome oxide (green rouge)
fbfd,Scale 8-9+ a9+
Al& Al& Si02 SIC Fe& CrJ4
process similar to that of fused aluminum oxide. The crystalline structure of Sic is a hexagon-type structure. Red Rouge The chemical formula for rouge is Fe,O,; it is also called jeweler’s rouge. Its purity is 99% ferric oxide. The crystalline structure of ferric oxide is spherical. Rouge is mainly used on precious metals to give an exceptional high luster. Green Rouge The chemical formula for chrome green oxide is Cr,O,. The hardness of chrome oxide is a 9 on the Moh scale as opposed to iron oxide, which is 6, and is used to produce an exceptional luster or color on ferrous, as well as nonferrous, metals. These abrasives are a small percentage of the materials available to give a specific finish required on a particular substrate. The relative hardness of each is shown in Table I. BUFFING WHEEL SPEEDS Although the wheel speeds for buffing with grease bars will vary greatly from job to job and operator to operator, the figures in Table II in surface feet per minute will serve as a guide for hand-buffing operations. Buffing wheel speeds for automatic operation may vary with the design of the machine and the contact of the work to the wheel. They can, therefore, be more definitely fixed without depending
9’6 6 8-9
upon the physical ability of the hand buffer to maintain the correct position and pressure against the wheel. LIQUID SPRAY BUFFING COMPOSlllONS Liquid spray buffing compositions have largely replaced bar buffing compositions on automatic buffing machines. Unlike the bar compounds previously discussed, the liquid buffing compound is a water-based product. The liquid buffing compound has three main constituents: water, binder, and abrasive. Water is used as the vehicle to transport the binder and abrasive to a buffing wheel through a spray system. The water and binder are reacted to form an oil/water emulsion. In this emulsion, the abrasive particulars are suspended and could be thought of as particles coated with a binder material. The emulsifying materials act as a device to hold the oil-soluble molecules onto the water molecules. Keep in mind that the abrasives are the same as used in bar compounds. The larger the abrasive particle, the less surface area present when compared with the weight of that particle. Surface area and density play an important role in the suspension of any liquid emulsion. Stability is the ability to keep the abrasive particle in suspension. When the abrasive particles tend to fall out of suspension, their weight factor is greater than the ability of the emulsified material to maintain stability. Viscosity, therefore, plays an important role in a suspension.
Table II. Suggested Wheel Speeds for Hand-Buffing Operations A&al Carbon and stainless steel Brass Nickel Aluminum Zinc and other soft metals Chromium
Cutfing Down (sfm)
Luster Suffhg (sfm)
8,000-9,000 6,000-9,000 6,OOC-9,000 6,00&9,000 5,000-8,000 7,000-8.000
7,000-9,000 6,OOO-9,000 6,00&8,000 6,000-7,000 6,000-7,OOU
35
hatever vour mass finishing requirements - in ’ quality, time cycles, operating v procedures and bottom line Washington Mills has a ceramic media in the right composition, density, shape and size to match... perfectly! Since 1868, our media has been evolving with the changing needs of industries like yours. Offering new choices for new products; and ever-superior results Washington Milk - World’s largest manufacturer of standard abrasive grains & specialty electrominerals as well as Boron Carbide.
on everything from golf clubs to 0 parts, jewelry to jet engine es to surgical instruments... and you name it! With Washington Mills, you take no chances. Quality, performance, consistency and durability are ALWAYS there. Plus service, expertise and experience unrivalled in the industry - from a pioneer and world leader. WASHINGTON Ceramics
MILLS Corporation
20 North Main Street North Grafton, Massachusetts 01536 Telephone: 508 839-6511 Fax: 508 839-7675 Telex: 6711292
of equilibrium for a defined period and at a constant temperature. A viscometer is used with a specific spindle. This reading, multiplied by a factor, will give a viscosity reading in centipoise. A plus or minus of 25% deviation is normal. The control of viscosity of a compound is somewhat difficult. Variations in raw materials or the method of blending are two reasons for viscosity changes. Viscosity is an arbitrary measurement. Liquid compounds are supplied to the spray guns by means of either airpressure feed tanks or high- and/or low-pressure drum pumping systems. The spray system needs to be designed to allow the liquid buffing compound to penetrate the air boundary of the rotating buff wheel and allow the compound to adhere to the wheel. Liquid abrasive compounds offer so many recognized advantages that their use is now accepted by the finishing industry as standard procedure for high-production buffing.
SUMMARY There are many other aspects of buffing and polishing than these briefly discussed here. Though this very important contributor to the metal-finishing industry is still a great deal more an art than a science, basic engineering principles can be applied. With the proper melding of buff and compound, applied in a controlled fashion, optimum finish and maximum economy can be achieved.
Circle 064 on reader information card
Biography The flow characteristics of a liquid buffing compound are controlled generally by the viscosity of that compound, as well as its degree of slip. The viscosity stability of any emulsion is established by its thixotropic nature, which means the viscosity becomes lighter in direct proportion to the amount of shear to which the compound is subjected. As the degree of slip is increased, the flow characteristics of the compound will also increase in direct proportion to the resultant change in slip or the resultant change in the coefftcient of friction. 36
The gel-type property of an emulsion is broken down by the action of the pump, thus producing viscosity changes. The changes are determined by the amount of shearing action of the pump and by the length of time. This breakdown is necessary to allow the transfer of the bufftng compound from the pump to the spray gun, which many times requires a significant distance. The viscosity of a liquid compound is measured under a constant set of conditions. To measure viscosity, a representative sample from a batch is needed. This sample must be in a state
Alexander Dickman, Jr. is Operation/ Technical Manager of Abrasive Products for JacksonLea, A Unit of Jason Inc., Waterbury, Connecticut. He has an A.D. in chemical engineering from Waterbury State Technical College and a B.S. in chemistry, with a minor in physics, from Southern Connecticut State University. He has been involved in the metal-finishing field since MF 1980.
METAL FINISHING . DECEMBER 1995