About Abrasives

8/13/2019 About Abrasives

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About AbrasivesYou will find here a general background on coated abrasives. These terms and concepts will giveyou a better understanding of the many variables which must be considered when choosing theperfect product for your particular application.Our technical staff will work with you to choose the proper backing, grain type and density, bondand joint to make your sanding operation more efficient.

How are they madeTwo processes are involved in the production of coated abrasives: manufacture and finishing. Themanufacturing process is a continuous operation that comprises the application of adhesives, theirpolymerization and the application of abrasive grains on the backing. This last operation is performed byone of two systems: one electrostatic and the other by gravity.In the first, the abrasive grains are passed into an electrostatic field where they become charged one endof each grain becoming positive and the other negative. A negative electrode used creating theelectrostatic field attracts the positive end of the grain particle and repels the negative end. Thus the grainis turned and applied in an upright position on the backing resulting in a uniform sharp and aggressiveabrasive surface.In the gravity system, the abrasive grains fall in a controlled manner on the adhesive coated backing. Thematerial thus processed can be coated according to the application needs, in a closed or open coat.

In the first case, the particles cover totally the surface of the backing and their use is adequate for severeoperation and for most applications. ost coated abrasives have this type of coating.In the second case, each abrasive particle is spaced at given distances, covering from !"# to $"# of thesurface. This coating loads less readily being effective in operations where the sanded material tends toclog the coating, for instance: solder, paint, varnish and woodworking.As a result of the manufacturing process large size rolls of different widths called %umbos are obtained,on which the finishing process begins. These %umbos are dried or cured and conditioned to the propermoisture contained for future processing into the form required. The rolls are stored and then cut to itsfinal form such as: &heets, 'iscs, (olls, )elts, *&A *aper 'iscs, +lap heels and &pecialties.FLEXINGThe fle-ing of a coated abrasive consists of a controlled fracture of the continuous adhesiveabrasivecoating at a certain angle and direction in order to obtain the degree of fle-ibility required for everyapplication and improve the performance of the coated abrasive.

There are basically three varieties of this operation: fle-ing, bifle-ing and fullfle-ing.In fle-ing, fracture lines of the material are perpendicular in relation to the edge of the material, forming a/"degree angle, which provides certain fle-ibility in the lengthwise direction.In bifle-ing, there are two fle-ing lines at 0! degrees, each in relation to the edge of the material,providing intermediate fle-ibility, that is, both crosswise and lengthwise.+ullfle-ing is a combination of the two above, that is, two fle-ing lines at 0! degree and one at /" degreein relation to the edge of the material. The result is a more fle-ible material, both lengthwise andcrosswise.ABRASIVE BELT JOINTSThe basic 1oins are either 2butted2 together or 2lapped2.3ap %oinsIn such a 1oin the abrasive grain is skived from end of the piece and the other end is lapped and glued onto this skived section. &uch a 1oin should only run in direction indicated.

)utt %oins2)utt splice2, in which belt ends are butted together and 1oined by high strength tape on underside of 1oint.Allows belt to run in either direction for greater belt life and convenience. &mooth running. ost popularsplice suitable for a wide variety of applications and belt sizes.

Abrasive FormsA selection of products is available in different forms such as: &heets, 'iscs, (olls, belts, *&A *aper'iscs, +lap heels and &pecialties.SHEETSThe abrasive sheets are cut to the standard size of /2 - 442 and come in paper or cloth, selectedaccording to the severity of the sanding operation. They are used by hand or with oscillating sanders andemployed for handcraft or in parts with difficult access for mechanical sanding.DISCS

These are circular or octagonal shaped coated abrasives with a vulcanized fiber backing. The mostcommon diameters are those of $2 - $562 and those of / 4562 - $562. The durability and strength of theirmaterials make them adequate for highspeed portable tools.Type of 'iscs:


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4. 7ircular ith 7enter 8ole: &tandard form and is fi-ed to the grinder by locating the center holeonto the spindle and this being held by a retaining nut.

9. 7ircular ith o 7enter 8olea. ;sually held on to a suitable backup by means of a pressure sensitive adhesive.b. 7ommonly referred to as *&A discs and can be produced in *aper or 7loth backings.

ot suitable for +iber backings.

PSA PAPER DISCSThese are special treated open coat material, e-cellent for finishing of primers, body putty, basecoat andclearcoat finishes, acrylic lacquers and dry feather edging. The pressure sensitive adhesive makes thesediscs easy to use, for dry sanding only.ROLLSThese are abrasive sections that come in different widths, from


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Effect of heat on the material

Above analysis should allow type of grain and coating to be selected ? i.e.:

TIMBER

Soft: arnet ! Silicon "arbide ! #$en coat

Tends to %oad: #$en coat

Hard: Aluminum #&ide ! "lose coat 'irconia Alumina ! "lose coat

META%

Hard: 'irconia Alumina ! "lose coat

Aluminum #&ide ! "lose coat

Soft: Silicon "arbide ! "lose coat Metal tends to surface(la)e

'irconia Alumina ! "lose coat

Silicon "arbide ! "lose coat

Tends to load or FillAluminum #&ide ! "lose coat $luslubricant

FI*ISH RE+,IRE-

Initial stock to be removed will decide the initial grade to use and the required finish the choice of the finalgrade.The intermediate grades if required should be chosen so that the previous grit scratch pattern can beremoved in one pass.A correct grit sequence will allow ma-imum value to be obtained from the coated abrasive product.;sually a grit sequence for a particular application and a particular material is determined by setting up atest program."H#I"E #F BA".I*If the work is flat, paper backing should be the material chosen unless there is the possibility of thebacking being snagged or torn.If the work is curved or shaped usually 7loth is the best product.here high tensions are required use 7loth.H#/ 0R#-,"T IS ,SE-

The amount of work to be done, stock to be removed, finish required, cost of labor will usually decidewhether application should be by hand or machine.If the work cannot be taken to the machine then some type of portable sander may be necessary.;se of 1igs, moulds, platen, etc. should also be decided if it will make the sanding 1ob less difficult ? lesscostly and achieve the desired results.rain Ty$esThe ability of the abrasive grain, which penetrates the articles being abraded, depends to a large e-tentupon the hardness, toughness and shape of the abrasive. The types of the abrasives used according totheir hardness are: &ilicon 7arbide, Alumina Firconia, *remium Aluminum G-ide, hite Aluminum G-ide,)rown Aluminum G-ide and Emery.SILICON CARBIDE&ynthetic mineral produced in electric furnaces, with a glossy black color and a high degree of hardness.'ue to its brittle characteristics it fractures into sharp silverlike wedges having cutting edges that permit

rapid stock removal. (ecommended for finishing nonferrous metals such as brass, bronze, copper andaluminumB and other materials such as leather, glass, wood, rubber and plastic. It is also used to finishand polish automotive primers, lacquers and sealers in general.ALUMINA ZIRCONIAIt is a mi-ture of zirconium o-ide dissolved in aluminum o-ide at molten temperatures. The type used forcoated abrasives has a microcrystalline structure and is characterized as sharp, hard and e-tremelytough. )ecause of the microcrystalline structure and e-treme toughness, smaller particles of the grainbreak off in use and at a much slower rate than standard aluminum o-ide. It produces superiorperformance on a wide variety of materials of both high and low tensile strength under high grindingpressures. aterials include carbon steel, stainless steel, tough bronzes, a wide variety of stainless steeland e-otic alloys, grey, malleable, ductile and nodular cast iron, aluminum, titanium, etc. Alumina Firconiais e-cellent on high grinding pressures applications and very often it is equally effective on many of thesesame materials at lower grinding pressure levels.PREMIUM ALUMINUM OXIDE (HT or Blue)&ynthetic mineral based on fused aluminum o-ide of high purity which has been thermically treated atvery high temperatures substantially improving its hardness and friability properties, due to these


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improvements, premium performance aluminum o-ide grain, maintains a sharp cutting edge that cutscooler, resulting in longer life and lower grinding costs. It is used for grinding high tensile strengthmaterials such as: steel, stainless steel and tough bronzes. It is also very effective for rough grinding ofmany low tensile strength materials such as: grey cast iron, low carbon steel, aluminum and brass, whenheavier grinding pressure used resulting in longer life and lower grinding costs.WHITE ALUMINUM OXIDE

hite Aluminum G-ide is a durable manufactured abrasive, which is characterized by the long life of itscutting edges. It is recommended for the sanding of all types of woods.BROWN ALUMINUM OXIDEThe )rown Aluminum G-ide grain has large crystal size in its structure. It is characterized as sharp, hardand tough, and it is used for grinding and polishing high tensile strength materials such as steel, stainlesssteel, tough bronzes, etc. It is also very effective for rough grinding many low tensile strength materialssuch as: grey cast iron, aluminum, brass, etc., when heavier grinding pressures are used.EMERanmade Emery is a regular aluminum o-ide with a low ferric o-ide content. The mineral enhances highdurability, recommended for hand polishing of ferrous and nonferrous materials.NON!WOVENSonwoven abrasive products offer a fle-ible, open structure which prevents cloggins and allowsconformity to irregular shapes. They are selfdressing and can be used wet or dry. onwovens come in

Aluminum G-ide and &ilicon 7arbide for a wide variety of applications in finishing and surfacepreparation. *remier manufactures belts, discs and pads in nonwoven materials.

Bac1in(sThese are the base materials supporting the abrasive grains. The types used are: *aper, 7loth,Culcanized +iber and 7ombination.PAPERThe paper used in the manufacture of coated abrasives is durable, strong and ideal for light applications,both by hand and with sanding devices, since the surface of the paper provides better finishes. Three areseveral weights or thicknesses of paper backings, from weight A @the lightest to weight E @the heaviest.+or wet applications, waterproof papers are used. These papers are impregnated with different types ofsynthetic elastomers that enhance important properties of the paper such as wet strength, pliability andresistance to moisture. 3ight papers are coated with fine abrasive grains, adequate for a final finish of the

materials. Those of intermediate weight are covered with coarser grains, adequate for intermediatesanding operations. The heavy or cylinder papers are coated with the entire range of abrasive grains andare recommended for manual or stationary sanding equipment. The principal difference between the lightand the heavy paper is strength: heavy paper has a lengthwise tensile strength almost twice that of lightor intermediate papers.*aper backings in use are:2A2 wt. $" grams per square meter @g.s.m. ? is a light and fle-ible paper usedby hand. 8and operation allows the operator to follow intricate curves2feet2 the surface imperfections during sanding.272 wt. 49" g.s.m. is a slightly heavier hand sheet than 2A2 wt. and is a moreeffective backing for the coarser grades.2'2 wt 4!" g.s.m., heavier than the 272 wt., stronger but still basically a handsheet, used on the coarser grades ? *6" and coarser.

2E2 wt. 99" g.s.m. is stronger and less fle-ible than the 2A2, 272, or 2'2 wts.Is used mainly on machine sanding applications. 8as high resistance totearing.2+2 wt.


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operations and5or where contour sanding is necessary.2H2 wt 'rills 7loth ? is a heavier, less fle-ible and stronger backing than the%eans 7loth. ;sed in heavy and medium grinding applications where+le-ibility is not important.2&2 &ateens is a 'rills 7loth that is stretch resistant for use on sectionalbelts ? belts wider than 4


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temperature and relative humidity occur, such cyclic changes can bring about rapid deterioration of thebond and the backing. *rovided coated abrasives are not sub1ect to e-treme variations of temperatureand (.8., performance should not vary greatly.&TG(AJE 7G'ITIG&

&torage and handling of resin fiber discs requires certain normal precautions. 'iscs should not besub1ected to e-treme atmospheric conditions.

Ideal storage is 9" degrees 7elsius @>6 degrees +ahrenheit. !">"# relative humidity.+or long storage leave discs in original packaging.(otate stock to insure freshness of supply.

E2ui$ment Ty$es. )-% !%*T S#+-%(Illustrates the basic principle of a single wide belt sander. ide belt sanders can come in manysizes and designs ? the basic principle is the same. A conveyor belt takes the work under or over

the sanding belts. ;sually the sanding heads are ad1ustable as to height per the work. )elttensioning is achieved by a hydraulic operated ram which moves the idler pulley closer to orfurther away from the sanding head. The second idler assists in tracking the belt. Also the topidler moves in a horizontal plane and keeps the belt in alignment ? this movement is achieved ina number of ways, but the activation of the pulley is caused by the belt intercepting a flow of aircutting off a photocell. ;sed widely in plywood industry ? particleboard ? metal sheet sanding ?furniture industry. )elt widths vary from >4"mm up to


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(ough grinding metal parts to a desired size @roughing and shaping, and finishing them to requiredtolerance and surface finish @dimensioning and finishing using coated abrasive belts.#brasive $laningJlued ?up or lumber banded manmade board panels prior to intermediate sanding or the application ofoverlays.#ccuracy

7onformity in dimension to an e-act standard.#ctive &illerA fine, solid material dispersed in the grain bond adhesive of a coated abrasive, which is chemicallyreactive during grinding to promote faster and5or smoother cutting action by the coated abrasive product.These materials are useful primarily in grinding stainless steels, other high nickel alloys, and titanium.#dhesiveThe substance used to bond the grain to the backing on a coated abrasive product.#lumina;nfused aluminum o-ide.#luminum O;ideAn abrasive made by fusing the mineral bau-ite.#nnealTo treat a metal, alloy, or glass with heat and then cooling, thereby removing internal stresses and

making the material less brittle.#rborThe spindle of the grinding machine on which the contact wheel or idler pulley is mounted.#rbor 0oleThe hole in the contact wheel or idler pulley sized to fit the machine arbor.#rc of "ontactThat portion of the circumference of the coated abrasive belt touching the work being ground, when on acontact wheel.#rea of "ontactThe total area of the grinding surface of a coated abrasive product in contact with the work being ground.#rithmetic 'eanThe average of a collection of numbers obtained by dividing the sum of the numbers by the quantity of thenumbers. Also known as average.

#ssembliesA term used to describe a section of abrasive used in the loading of a Connegut 8ead )rush &ander.Available with the pieces either straight scored, staggered scored, or unscored, these cloth specialties areused for fine sanding of contoured wood parts when finishing is required without destroying characterlines.#utomatic TrackingA system that ensures the coated abrasive belt runs true on a contact roll or idler. These automatictracking systems are usually tight of all controllers and constantly ad1ust belts during operation to achieveideal and consistent tracking.!ackingA fle-ible or semirigid material to which abrasive grain is bonded by an adhesive. *aper, cloth, fibre andcombination are the ma1or backings used for coated abrasives.!ack $ass

A light grinding cut taken on the bottom @back side of coil or sheet material, to relieve stresses fromrolling and to prevent distortion from occurring during subsequent grinding operations on the finish side.!ack Satin&moothing the print side of coated abrasive backings to retard platen wear during use. The process isemployed primarily for wide and narrow belt applications involving fine and coarse grit polyester products.!ackstandGne of the most popular industrial abrasive belt machines for offhand or other grinding and finishing.*referably floormounted, it usually provides tracking and tensioning controls. ork is applied to thecontact wheel below the centerline.!ack


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A wheel or roll is in static balance when, centered on a frictionless horizontal arbor, it remains at rest inany position.!ands 8#brasive9&pirallywound and bonded to an inner liner, these cylindricallyshaped cloth specialties are used one-panding rubber drums for sanding and polishing hardtogetat corner, grooves, and contouredsurfaces.

!arber $oleA spiral pattern produced on a workpiece during centerless or cylindrical grinding. ormally caused byimproper operating conditions.!atch SystemIn rough lumber sanding, several boards of equal or unequal widths of the same relative thickness areaccumulated side by side into a unit roughly equal to the width of the abrasive belt in use. This 2batch2 isthen fed into the sander and all the boards are sandedsimultaneously.!elt uardA protective device covering the abrasive belt, which is normally an integral part of the grinding machineused to protect operators and bystanders from personal in1ury.!elt =ointThe area of an abrasive belt where the two ends are spliced together with an adhesive. &ee )utt %oint

and 3ap %oint.!elt =oint 'arksA pattern left on the workpiece at regular intervals, normally caused by a belt 1oint specification that is notsuitable for the application.!elt TensionThe force or strain put on a coated abrasive belt during use, normally e-pressed in pounds per inch ofbelt width.!ench StandAn offhand grinding machine attached to a bench, usually has either one or two wheels mounted on ahorizontal spindle.!i @&ee 'ouble +le-.!illy (oll

A pneumatic or hydraulicactuated pressure roll used to apply pressure forcing the work against a widecoated abrasive belt.!lending;sing abrasives to develop a consistent finish over an entire workpiece as on a welded area.!oard &ootA unit of measurement for lumber equal to the volume of a board 492 - 492 - 42, i.e., 400 cubic inches.!ody


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A change in the characteristics of the workpiece being ground. ormally detected by a surfacediscoloration or distinct 2burning2 odor.!urnishing;sing coated abrasives to create a special effect on a workpiece @refining the surface. ;sually done todevelop a smooth, lustrous surface finish on metal, leather, etc.!urrs

A thin, ragged tin left on the edge of a piece of metal by a cutting tool @including coated abrasives.!ushingA metal or plastic insert used to alter the size of a center hole @primarily in rolls or +lap heels toaccommodate a smaller mandrel or arbor.!utt =oint 8!elt9Two pieces of coated abrasive 2butted2 together @with no overlap to form an endless belt. A very strong,thin, reinforcing patch is used on the back of the butt 1oint to hold ittogether."abinet (oom 8&urniture9The assembly area in a furniture plant where case goods are sanded inthewhite, prior to staining."alendar (oll&teel, rubber, or rolls of other composition, through which materials such as paper, steel, etc., pass to thinthem into sheets or to make them smooth and glossy. A roll, usually rubber, that applies the adhesive

@bond to a coated abrasive backing prior to the grain coating."#$ "odeA simplified system used to identify the various coated abrasive products."artridge (oll&ee *encils."astingAny ob1ect @usually metal or plastic, which is formed by placing a @castable substance in a mold or form,and allowing it to solidify through cooling."enterless rindingAbrasive grinding and finishing the outside diameter of a round workpiece not mounted on conventionalcenters @&ee 7enterless Jrinding Application &ection of manual."enters7onical steel pins of a grinding machine upon which the workpiece is 2centered2 and rotated during

grinding."hatterAn undesirable, repetitive pattern created on the surface of a workpiece, usually at regularlyspacedintervals, due to an outofround or outofbalance condition in the abrasive machine.>"hicken>Treats&mall interrupted indentations or raised areas, appearing as a pattern, on a flat wood workpiece aftersanding. ormally associated with wide belt or oscillating drum sander applications."hips*ieces of material removed by an individual abrasive grain during the abrasive grinding operation."huckA device for holding a workpiece being ground."laddingA process by which two or more @usually dissimilar, e.g., stainless steel and copper metals are bonded

together with heat and pressure, to form a composite surface without the use of any adhesive."limb rindingThe workpiece is presented to the abrasive belt in the same direction the belt is running."losed "oatA coated abrasive product completely covered by abrasive grain on the coat side."oated #brasives*roducts formed by bonding abrasive grain with an adhesive to a fle-ible or semirigid backing."oloring 8"olor !uff9(efers to an operation that generates high lustre or ultrafine finishes on metal surfaces using buffingwheels and compounds."ombinationA strongcoated abrasive backing made by adhering print cloth to 44" pound paper."ombination Sanding 0ead

A wide belt grinding head that offers the option of using the contact roll or platen either individually or intandem."ompensator


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An equipment option on wide belt sanders that reduces the feed speed of the work transport system whene-cessively oversized work enters the machine. This feature improves coated abrasive belt life andreduces machine wear."oncave 8"url9A coated abrasive product with a curved @curled configuration, which bulges inward. The abrasive grainis always in the inside curve @grain side concave.

"oncentrationThe relative content of a component usually e-pressed as a # of total, e.g., grain coverage, amount ofinert filler I adhesive bonds, etc."ontact heelThe wheel, usually rubber, metal, or felt, over which a coated abrasive belt runs and against which work isapplied. Aggressiveness varies with density, angle, and depth ofserration @if any and ratio of groovewidth to landwidth."ontour SandingThe sanding of irregularshaped parts or compound moldings."onventional rindingThe workpiece is presented to the abrasive belt opposite the direction the belt is running."onveyor !elt;sually an endless belt configuration that positions, holds, moves, and finally clears workpieces through

the abrasive heads on a grinding machine."onveyor 'achineA coated abrasive grinding machine on which the workpiece is moved by a belt under the abrading headof the machine."onve; 8"url9A coated abrasive product with a curved @curled configuration which bulges outward. The abrasive grainis always on the outside curve @grain side conve-."oolantThe liquid or solution used to cool the workpiece during grinding, and to prevent it from rusting."reasing 8of a !elt9+olding of the coated abrasive belt on the contact roll or wheel because it has become stretched inservice, or is too fle-ible for the operation. The term is also used to describe a light scoring of the back ofthe belt so that it will 2hinge2 and fit into the comple- shape of a hand block.

"rocusEssentially Iron G-ide in natural or synthetic form, 7rocus coated products are used mostly for cleaningcorroded surfaces of polished metals where a minimum of stock removal is desired."ross


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-imensionsThe size of a workpiece or coated abrasive product ? normally e-pressed in measurement of length,width, and often depth, e.g., 0L - 6L plywood sheet, M2 thick, or a 02 - 4


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Jrooving or rounding of the edges of work caused by e-cessive stock removal at the coated abrasive beltedge. Also called edge snipe.%dge SanderA machine used for edge sanding in a furniture plant.%dge SandingThe sanding of any furniture components requiring flatness and squareness integrity, such as frame legs,

end boards, etc.%dge ShedA term used to describe a condition in which the abrasive grain 2shells2 off the edges of a coated abrasiveproduct @usually a belt during use. ;sually caused by too severe an application of the coated abrasiveproduct.%meryAn abrasive that is a natural composite of 7orundum and Iron G-ide. The grains are blocky, cut slowly,and tend to polish the material being abraded.%nd rainThat portion of a cut piece of wood, which e-poses the growth rings of a tree. An e-ample is the end of a9 - 0.&.%.$.#.2+ederation of European *roducers of Abrasives2 ?

ormally used to describe a European grading system for abrasive grain to differentiate it from the ;&AA..&.I. system. *roducts graded to the +.E.*.A. system have the letter 2*2 prior to the grit designation,e.g., *90", *.&eed 8"ross9Gn surface type sanding operations @i.e., stroke sanding, the rate of horizontal feed of the coatedabrasive across the work.&eed 8-own9Gn conveyor operations or surface sanding, the distance at which the belt and contact wheel are fed intothe work.&eed *inesA pattern on the work produced by grinding. The finer the finish, the finer and more evident are theselines, due to surface reflectivity. &ome types of feed lines @barber pole indicate incorrect grindingconditions.

&errousAny metal alloy containing iron, usually in ma1or amount.&iber 8!acking9A very hard, strong, coated abrasive backing material consisting of multiple plies of impregnated paper.;sed primarily for disc products.&ibre "ombinationA strongcoated abrasive backing made by adhering print cloth to 4"mil thick fibre.&inA thin pro1ection on a casting.&ining OutJenerating super fine finishes on a workpiece during the last stages of a coated abrasive polishingoperation. Either the last step in polishing, or as preparation for subsequent buffing.&inish

The surface quality of appearance, such as that produced by sanding or polishing.&inish rindingThe final operation which produces the desired finish on the workpiece.&inishing $aper*roducts manufactured on 2A2 weight @0" pound backings, normally in fine grits, usually used to handsand for final finish on wood, metal, etc.&inishing (oom(efers to the area in a furniture plant where the primary sanding operations for finishing furniture areperformed, including wash coat sanding and sealer sanding.&ish %yeA spot in a finished coated surface, where the coating is sufficiently thinner than in surrounding areas tocause a visible blemish. This defect is usually caused by the presence on the surface, before coating, of aminute trace of some chemical which prevents easy wetting of the surface by the coating materials.

&ilicones are one of the most common classes of chemicals oft his type, and, as a consequence, they arerigorously e-cluded from highquality coated abrasives.&i;tureA device used to hold and position the workpiece during the grinding and polishing operations.


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&langes7ircular metal plates used to support and drive contact wheels, )EA(TEH heels, or +lap heels.&lap heel+lat pieces of coated abrasive sheets @flaps arranged and fastened together on a core like spokes of awheel. The rotational slapping action of the flaps does the abrading and polishing.&lashing

A fin of e-cess metal along the mold 1oint line of a casting, occurring between mating die faces of aforging or e-pelled from a 1oint in resistance welding.&lesh !uffingechanical sanding of leather, e.g., leathers that are finished by buffing the flesh side @opposite the grainside to produce a nap. The term 2flesh buffing2 refers to the napping process, and is unrelated to the typeof animal skin used.A controlled breaking of the adhesive bond that holds the abrasive grain to the backing of a coatedabrasive product.&lutingJrinding the grooves of a twist drill or tap.&lutter Sanding&anding irregular, intricate shapes or carvings which may be found on furniture frames, legs, chair backs,

etc. ormally done with eight winged 'e3appe 'iscs folded into a pinwheel configuration.&oamingA frothing of bubbles on the surface of a liquid. ;sually refers to 2foam2 in grinding aids, etc., during thegrinding process.&oldingormally refers to creasing of a coated abrasive belt during use. @&ee 7reasing.&orging;sing compressive force to shape metal by plastic deformation. 'ies may be used. Also refers to a pieceof work made by forging.&reehand rindingJrinding by holding the work against the coated abrasive by handB usually called Gffhand Jrinding.&riable(eferring to the property of a substance capable of being easily rubbed, crumbled, or pulverized into

powder.&TSAbbreviation for +ull Top &kive @a type of belt lap 1oint configuration. All of the grain is removed from thetop lap of the 1oint for smooth running.apped =oint(efers to a belt 1oint condition in which the two 1oint ends do not butt tightly together. There is a space or2gap2 at the point of contact of the belt ends. 7ondition may lead to premature product failure.arnetA coated abrasive grain, red in color, made by crushing semiprecious garnet material. 7oated on bothcloth and paper backings, Jarnet is widely used in the woodworking and furniture manufacturing industry.ateThe part of a casting formed by the opening in the mold through which the metal is poured.enerated 0eat

8eat resulting from the removal of metal or wood by a coated abrasive product.la?ing+ormation of a layer of the material being ground over the cutting edges of abrasive grains. It can beavoided by proper selection of abrasive, contact wheels, use of fluids or greases, or changing beltspeeds.lueA coated abrasive adhesive produced by the hydrolysis of animal hides. It is gelatinized by water anddries to form a strong adhesive layer and may be used with or without a filler.lue !ond7oated abrasive products that use animal hide glue in both the maker and sizer adhesive coats. The gluemay be used alone or with an inert filler or e-tender..$.'.Jallons per minute.

radingThe process used to separate abrasive grains into specific size groupings.rainAbrasive particles classified into predetermined sizes for use on coated abrasive products.


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rain &racture(efers to the shape and structure characteristics of abrasive grain used for coated abrasive products,e.g., blocky, chisel shaped, strong wedges, etc.rain Si?eThe nominal size of the abrasive particle e-pressed in grit number, e.g., grit !".rain Spacing

The relative position of the abrasive grain on the coated abrasive product, usually e-pressed as opencoat or closecoat.raphite "oated "anvas7anvas with a layer of graphite adhered to it. 'esigned to reduce friction on a platen type grindingmachine, it is used between the platen and the back of the belt.ravity "oatA process by which the abrasive grain is applied to the adhesive coating @of a coated abrasive product bygravity flow.rease Stick7ompounds of grease, lubricants and binders sold in 2stick2 form, which are applied to the coatedabrasives during use to retard loading and improve metal finishes.rinding(emoving material with a coated abrasive product, usually referring to the use of coarser grit sizes.

rinding #ction(efers to the cutting ability of, and the finish produced by, a coated abrasive.rinding #idThe generic term covering coolants and lubricants applied to coated abrasives to improve cut, finish, anddurability by reducing heat and loading. ay be water, various oils @in emulsion or straight, or greases instick form.rinding !urr&ee )urrs.rinding heelA cutting tool of circular shape made of abrasive grains bonded together.rit'esignation of abrasive grain size, reflecting the number of the smallest openings per linear inch in thescreen through which the grain will pass.

roove(efers to the slots in a serrated contact wheel or roll ad1acent to the lands. 3andtogroove ratio hassignificant bearing on the aggressiveness of a contact wheel.uardsetal structures covering e-posed moving parts @flywheels, gear, etc., as well as the abrasive product,on a grinding and polishing machine, designed to protect operators from personal in1ury.0and !lock Sanding;sing a flat block or formed block when sanding with belts or sheets, usually to finish wood workpieces.+lat hand blocks are used to polish flat stock, while formed blocks are sued to sand shaped moldings.0eadingA technique used to improve the finishing characteristic of abrasive belts. The process impacts the voidsbetween abrasive grains with a combination of oil and generated swaff, to retard penetration of theabrasive into the surface being polished, in order to produce uniform, burrfree finishes.

0eat "heck*arallel surface cracks forming a pattern on the surface of a metal as a result of thermal fatigue.0eat "rackA crack or fissure in a workpiece caused by e-cessive heat generated during the grinding operation.0eel Scouring&having the heels of shoes with a cutter to conform to the shoe shape leaves a ragged, uneven edge. It isnecessary to bring @scour the edge to a smooth, even surface which wa-ing and burnishing will keepbright and shiny. &couring is accomplished with silicon carbide coated abrasives.0olddownA device that holds the outer portion of a metal sheet in place during deep drawing operations, in order tokeep it from becoming wrinkled. ;sed to describe any fi-ture for holding a workpiece in position during agrinding operation.0oods

A protective covering, usually providing special ventilation, to carry away ob1ectionable fumes, dusts, etc.,during the grinding process.)dler


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A machine part in a belt system @may be ad1ustable which provides belt tracking and, in someinstallations, belt tensioning ad1ustments.)dler roovesA configuration of slots or grooves in an idler roll of an abrasive belt machine to prevent coated abrasivebelt hydroplaning during a wet grinding operation.)nclusions

;sually mean cavities denoting impurities in metal workpieces.)nde;ingA programmed progression of grinding across a surface. To move the 2feed2 in steps.)n


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+illing of the spaces between abrasive grains on a coated abrasive product with grinding swarf, resultingin a decrease in stock removal and rate of cut. 3oading can be reduced in many operations by using anopen coat product construction or a lubricant.*oad 'eterAn optional feature on wide belt sanding equipment. A meter that reads out the main motor load duringoperation. &ome meters are calibrated in percent of rated horsepower.

*ong Scratch&cratch pattern @long scratches e-hibited on a workpiece after stroke sanding or flat platen type sandingvs. a short Oscratch2 from a contact wheel or roll operation.*ubricant3iquid or solutions used to lubricate the coated abrasive for cooling and to promote a more efficientcutting action.'achine (oomThe area of a furniture plant where the rough cut lumber is dimensioned, glued into panels, andmachined. The dimensioning portion of this operation is frequently carried out on wide belt abrasiveplaners.'agnetic $latenA platen that is magnetized to hold @secure ferrous metal parts during the grinding operation.'aker 8'achine9

A machine that manufactures coated abrasive products by combining the backing, adhesive, andabrasive grain.'akingThe process of producing coated abrasive products.'aking "oatThe first adhesive coat which adheres the abrasive grain to the backing of a coated abrasive product,thereby ensuring proper anchoring and orientation of the abrasive grain.'alleable7apable of undergoing plastic deformation without rupture. A property characteristic of metals that makesthem easily 2workable2.'andrelA metal rod or support used to mount &*I(A*GIT&, *encils, cross and square pads, disc sets, or loosepieces of coated abrasives to be held in the chuck of a grinder for grinding and polishing.

'TS =ointedium Top &kive ? &tandard top lap 1oint skive depth for a T% coated abrasive belt 1oint, grits 0" through6". &ome of the grain is removed from the 1oint top lap.'atte &inish'ull, as applied to the appearance of a surface.'a;imum Operating Speed8ighest permissible operating speed @(* marked on a coated abrasive disc backup pad or +lapheel.'icro &inishA measure of surface finish. ;sually e-pressed in (& @(oot ean &quare.'icron Si?eA unit of measure used to compare abrasive grain size, e.g., 4 micron N .""""


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'Y*O7A butt type belt 1oint similar in construction to *3DE3'. This 1oint utilizes a very thin plastic patchmaterial designed to give 2bump free2 operation of the belt when the 1oint is run over a steel platen orused with a very hard contact wheel.+ailboard'escribes a small, thin wooden fileshaped board to which coated abrasive products are affi-ed to each

sideB usually fine grit +lint on one side ? fine grit Jarnet on the other. ;sed to file and trim fingernails.+atural #brasives;sed to differentiate abrasives that occur in nature as opposed to electric furnace type abrasives. aturalabrasives used for coated abrasives are Jarnet, +lint, 7rocus and Emery.+on


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&mall holes in the surface of a metal, usually caused by corrosion or formed during electroplatingoperations.$lastometerInstrument used to determine the flow properties of a thermoplastic resin by forcing molten resin througha specified die opening or orifice at a given pressure and temperature.$laten

A flat or shaped support which backs up a coated abrasive belt in the area where the workpiece isapplied. ;sually metal or wood, the platen may be surfaced with resilient material and a lubricant such asgraphite covered canvas.$laten rinderA coated abrasive machine utilizing a platen. The platen provides an area contact to the coated abrasive.;nit pressures are usually low.$lunge rindingThe grinding or polishing of an entire surface in one thrust as opposed to several passes. 'irect infeed isusedB there is no crossfeed. The abrasive belt must be wider than the workpiece.$neumatic -rum Sanding7ontour sanding of chair stock and related parts with coated abrasive sleeves mounted on canvascovered inflatable rubber drums.$olishing

Act of smoothing off the roughness or putting a high finish on metal by using a coated abrasive polishingbelt.$olishing =ackA machine that uses setup wheels or buffs for polishing. Cery easily converted to use coated abrasivebelts.$olyesterA synthetic cloth material used as a backing for coated abrasive products.$ortable rinderA coated abrasive sanding machine that is used by hand @manually and can be easily transported, e.g.,portable disc and belt sanders.$ouncing $aperA coated abrasive paper used to 2pounce2 or finish felt hats. The pouncing process removes hair fibres,producing a smooth, even nap on hat crowns and brims.

$recision orkork which is required to be e-act in measurements, finish, etc. ork that must be ground with greatcare.$ressure #ssist;sing a pneumatic or hydraulic fi-ture to present the workpiece to the belt. Incorporates uniform andfaster stock removal by maintaining constant pressureB lessens operator fatigueB eliminates overgrindingand ensures part uniformity.$rofile(efers to the surface configuration of a workpiece, namely. 'etail of grinding surface, finish, flatness, etc.$rofilometerAn instrument for measuring the degree of surface smoothness in micro inches, 2(&2.$S# 8$ressure


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;sed in centerless grinding, regulating belts are either a coated abrasive product or made from leather ora rubber belting composition. They are run over a steel platen, normally with a carbide insert to preventwear, and function the same as the regulating wheel.(egulating heel;sed in centerless grinding, regulating wheels function both as a frictional driving and braking element,rotating the work at a constant and uniform surface speed.

(esinA synthetic adhesive used as a bonding coat for coated abrasive products.('S 8(oot 'ean S@uare9A measure of surface finish.(ockwell 0ardnessA measure of hardness of a material as determined by the (ockwell hardness test.(oll rinding 'achineA machine for grinding cylindrical rolls, used for rolling metal, paper, or rubber.(ollsA form of coated abrasives @usually in !" yd. 3engths in widths from 2 to !92. &old in roll form to beconverted by the customer.(ough rindingThe first grinding operation for reducing stock rapidly without regard for the quality of the finish.

(ough *umber Sanding(efers to the first sanding operation on lumber, after the sawing operation.($'(evolutions per minute.(ubbingThe final phrase of finishing in which the part surface is 2rubbed 2 by machine or hand to give the requiredlustre.Sanding (oom'esignates a department in a furniture plant that is devoted primarily to machine sanding of dimensionstock prior to assembly.Satin &inishA smooth but not highly reflective surface finish on metal.Satining

A precision leveling of the coated abrasive surface to ensure against scratching of soft materials.Scalloped %dge !elts)elts with edges slit in the pattern of a scallop. ;sed to overhand the edge of a contact wheel to grind orpolish a fillet in a workpiece.ScleroscopeAn instrument for determining the relative hardness of material by a drop and rebound method.Scored (olls7oated abrasive roll material with parallel slits evenly spaced in the length direction. ;sed for makingassemblies.Scratchingarks left on a ground surface by dirty coolant contamination or improper coated abrasive specificationfor the operation.Sealer "oat

A coat of finishing material @generally nitrocellulose in nature designed to close the pores on wood andpromote adhesion of subsequent finishing materials.Sealer Sanding(emoving the roughness or surface impurities from the sealer coat surface prior to the finish lacquer coat.Seaming lass&moothing and easing of the edges and corners of flat glass prior to tempering.Sectional !eltA coated abrasive belt made of sections spliced together to produce belt widths greater than thema-imum product coating width. 7ontains two or more 1oints per belt.Serrated "ontact (oll7ontact roll or wheel with grooves milled into the face to increase the cutting action of the coated abrasivebelt and prolong belt life.S&$'

&urface +eet *er inute.SheddingTerm used to denote the loss of abrasive grain from a product during the grinding process.Shelling


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&ee &hedding.ShoeTechnically referred to as a platen or smoothing bar. A flat metal support located behind the coatedabrasive belt. +requently faced with felt or vinyl foam tape to provide resiliency.Shore -urometerA method of rating the hardness of rubber, plastic, or other material.

Short ScratchJenerated by a contact roll application as opposed to a stroke sander or platen type operation.Silicon "arbideAn abrasive made from coke and silica sand @&I7.Single A controlled breaking of the adhesive bond of a coated abrasive product at a /" degree angle to thelength. The coated abrasive product is stiff in one direction, fle-ible in the other.Si?e "oat&econd adhesive coat applied to a coated abrasive product. The 2size2 coat unites with the maker coatand insures the final anchoring of the grain and propre total adhesive level to the finished product.Skive(efers to the grain removal and taper operation performed on both laps @ends of coated abrasive beltprior to 1oining the two laps necessary in order to achieve adequate 1oint adhesion and desired 1oint

thickness.Slack of !elt SanderA machine configuration in which the workpiece is presented to the coated abrasive belt in the areabetween the two pulleys. ork applied to unsupported area of belt.Slag rindingA wide belt conveyor type grinding operation that replaces portable tool grinding methods for removingslag, scale, and torch splatter from the surface and edges of flame cut and5or plasma cut steel parts.SliversThin, elongated fragments of metal that have been rolled into the surface of the parent metal and areattached by only one end.Slotted -iscs7oated abrasive discs containing numerous radial slots cut from the outside periphery.Slurry "oat

(efers to a coating method in which the abrasive grain and adhesive are mi-ed together and meteredonto the backing in one continuous coating.Smoothing !arA platen type device backing up the coated abrasive belt at the point of contact with the workpiece.;sually covered with graphite canvas to reduce frictional heat. ;sed on wide belt machines inwoodworking, particleboard and plywood sanding to promote better finishes.SnaggingJrinding the gates, fins, and sprues from castings.Soluble OilAn emulsifying oil which, when mi-ed with water, forms an emulsion. &oluble oil mi-tures are sometimesused to achieve better finishing than can be produced by dry grinding or by water alone. The water freesthe belt of particles and the oil prevents rust from forming on the e-posed machine part.Specialties

7oated abrasive forms other than sheets, rolls, belts and discs, e.g., assemblies, +lap heels, cones,etc.Spindle&ee Arbor.Spool Sanding&anding conve- or concave profiles on curves such as mirror frames, headboards, and other compoundshapes. &ee *roduct Application and &election &ection for &pool &anding.Spray 'istA method of supplying coolant to the workpiece or coated abrasive belt during metal finishing operations,as opposed to a full flood coat.Stamping !urrA burr caused by stamping dies.Steady (est

A support for workpieces being ground on a cylindrical grinding machine.Straight *ine Sanding(efers to a simple reciprocating type hand sander as opposed to a sander employing orbital motion.Strapping


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Thin %oint ? &pecial coated abrasive belt lap 1oint construction for use in applications where a smoothrunning product with minimum 1oint thickness is a necessity.TolerancesThe permissible variations in the dimensions of machine parts or the permissible deviation from aspecified value in a manufacturing specification or procedure.Tooth

Gne of the regular pro1ections on the edge or face of a gear wheel. The coarseness or abrasive quality ora surface, e.g., roughing a surface for better adhesion of veneers, etc.Torn %dge !eltA coated abrasive belt fabricated with one belt edge torn lengthwise and 1oined along a warp thread toensure straight tearing of subsequent narrower belts when they are ripped. ;sing the torn edge of theoriginal belt as a starting point, narrower width belts can be ripped in succession across, until the originalbelt is used up.TrackingThe act of ad1usting the idler pulley in a coated abrasive belt system so that the belt is properly aligned onthe contact wheel.Traverse Speed&peed at which either the grinding head or the workpiece moves laterally during grinding or polishing.Triple

A combination of &ingle +le- and 'ouble +le-. &pecified on certain products for sanding irregularcontours where ma-imum product conformability is a requirement.TruingThe procedure used to restore a flat surface to a contact wheel or platen.TumblingAn operation for deburring, breaking sharp edges, finishing, or polishing, in which abrasive, water, and thework parts are 2tumbled2 in rotating or vibrating barrel.+)&*O !elt&ometimes called 2&leeves2, this abrasive specialty is formed with a belt type 1oint. ;sed on soft drums atrelatively low speeds for removing tool marks and developing special finishes. Available in widths upthrough /2 and lengths up through 442.p "oat(efers to an electrostatic method @upward propulsion of coating abrasive grain on a coated abrasive

product./ickersA system for measuring metal hardness using a triangular diamond which is pressed into the metalsurface under a fi-ed preload./onnegut #ssembly&ee Assemblies./onnegut heel)rushbacked wheel containing a loading of coated abrasive strips, used to sand contoured workpieces.ash "oatA very light coat of finishing material primarily adding depth to the color of furniture after staining. Thesolution is sprayed on and requires light scuffing.aterproof #brasiveA coated abrasive which will withstand grinding with water or water soluble oil as a grinding aid.

eak Shaped raineedle shaped, very friable, easily fractured abrasive grain, as opposed to 2strong shaped grain2.eb(efers to a flatcoated abrasive product, usually in full width form, as it passes through the manufacturingprocess.et rindingA term used to describe full flood oil grinding and full flood water soluble methods. All methods other thanabsolutely dry are included.hiting+inely ground clay and5or limestone used to absorb oil from stainless steel after polishing.ild ScratchA heavierthannormal scratch in a workpiece finish. ;sually intermittent or random, caused by a coarseparticle, contamination of swarf, etc.

ork (est !lade&upports the material being ground during a centerless grinding operation.ork (est !lade #ngleAngle at which the work rest blade meets the workpiece ? 9" degrees to


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ork (est !lade 0older8olds work rest blade in position during centerless grinding.ork SpeedIn cylindrical and centerless grinding, the rate at which the work revolves, measured in either (* or&+*. In surface, conveyor, or feed type grinding, the rate of work presentation to the coated abrasive,measured in +* @feet per minute.

Yield(efers to the total amount of processed lumber realized from a 3og.Birconium #luminaA term used to describe coated abrasives which utilize a special synthetic grain that gives the mosteffective performance in a variety of applications.

"loth !acking

Type $roperty !acking' R4"

E R99" 9$"

+ R9$"

&iber

Type #verage thickness

%fle- ",0 ",!! mm

% ",> ",>! mm

H ",6 ",6! mm

&ilmType

*E& N *olyester
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#brasive rains and rain Standards

rain rain Standard

A5G @Aluminum G-ide * N +E*A 'I >/ 4$>

&apphire )lueS @microfractureAluminum G-ide * N +E*A 'I >/ 4$>

&57 @&ilicon 7arbide * N +E*A 'I >/ 4$>

F5A @Firconia Alumina N A&I )$0.464/60

Jarnet N A&I )$0,464/60

8ermesit * N +E*A 'I >/ 4$>

!onding Systems

!onding -escription

(esin

(esin, antistatic

(esin, *rocut &ize coat with active additives

(esin, *rolub Applied stearate coat, or active additives in the size coat

Jlue

Jlue, *rolub Applied stearate coat, or active additives in the size coat
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About Abrasives

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