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VII. Speed Gluing Table Tennis Rackets
Experience has shown that to achieve the maximum performance from regluing, a fresh sheet of rubber needs to be "primed" before it can be reglued. This entails putting two or three thin layers of speed glue on the sponge prior to its use on the racket. Each of the layers should be allowed to dry completely before placing another layer on the sponge. After the final priming layer is dry, it is best to wait at least eight hours and preferably twenty-four hours before the sheet is ready for regluing and putting on a racket. One reason for this is that the glue solids (as opposed to the solvents, which evaporate), need a number of hours to develop a stable strong bond with the sponge. If one does not wait a long enough time for the solid layer to bond, the spin component of the rubber will be reduced and the sheet may not stick to the racket face securely.
A. Priming the Rubber for Regluing
To achieve the maximum performance from regluing, a fresh sheet of rubber needs to be "primed" before it can be re-glued. This entails putting two or three thin layers of speed glue on the sponge prior to its use on the racket. Each of the layers should be allowed to dry completely before placing another layer on the sponge. After the final priming layer is dry, it is best to wait at least 8 hours, and preferably 24 hours, before the sheet is ready for regluing and putting on a racket. One of the reasons for this is that the solids of the adhesive system (as opposed to the solvent, which evaporates), needs a number of hours to develop a stable, strong bond to the sponge. If used before the solid layer has bonded, the spin component of the rubber will be reduced and the sheet may not stick to the racket face securely.
One easy way to judge the amount of glue to place on the rubber is to pour an amount out onto the center of the sheet. The diameter of the circle tells the amount of glue being used very accurately. For priming sheets, a circle of glue of about 1.5 inches (35 mm) in diameter can be used for each priming. Another technique is to count the number of times a brush is dipped into a can. The diameter method is better, however, as it is easy to remember and judge.
B. Amount of Glue to Use on the Sponge
A major consideration for the player when deciding how much glue to apply is how much performance boost is required. To achieve a minimum effect, the diameter of glue applied should be at least 1.5 inches (35 mm). The rubber should dome up in a few minutes. The height of the dome depends on a number of factors, including: (1) the softer the sponge, the higher the dome; (2) the thinner the glue build-up, the higher the dome; (3) the thinner the sponge thickness, the higher the dome; and (4) the higher the air temperature, the higher the dome.
The height of the dome is a very good indicator of the potential performance of the sheet. However, a sheet does not always require a big dome to have a performance boost. With experience it is possible to judge from the dome size which effect is likely to occur from a particular amount of glue used. In some circumstances the amount of glue must be adjusted to achieve the same dome. For example, if the sheet has a large glue build-up, more glue may have to be applied than normal to achieve the same dome and therefore the same performance as in previous gluings. This is also true of gluing in cold temperature conditions.
There are a number of doming stages that a rubber sheet can go through, including: (1) a mild dome--having a height of approximately 1" (25 mm); (2) a medium dome--having a height of approximately 2" (50 mm); (3) a high dome, wherein the sheet develops heavy curl; and (4) an extreme dome, wherein the sheet curls up into a tube.
To achieve a big speed glue effect versus a mild effect more glue needs to be applied. However, instead of putting on a large amount of glue at one time, more than one application of glue should be applied, and then one must wait until the rubber has achieved its maximum dome after approximately five to seven minutes. If the dome is not sufficient, another layer of glue needs to be applied using a glue diameter of about 1.5 inches (35 mm) for each application. On sheets which already have a considerable glue build-up, maximum performance can be achieved by using the solvent systems alone, instead of the adhesive systems.
In order for the rubber sheet to stick properly on the blade, a fresh layer of glue needs to be applied on its face. The amount of glue needed depends on a number of factors, including: (1) whether or not the blade has been used before; (2) whether the face is rough or smooth; and (3) whether a sealer has been put on the face and, if so, the type of sealer employed.
For a previously used blade having an average roughness, start with a circle of glue about 1 inch (25 mm) in diameter. Brush the glue over the entire face evenly. If there are any dry spots cover them with glue, obtaining the glue by dipping the brush into the bottle. If it appears that edges might curl, cover the edges with a second application of glue by the dip method.
On a brand new blade, apply two thin even coats of glue. The first coat should be allowed to dry before applying the second coat. If the sheet does not sticking properly with a 1" (25 mm) circle of glue, then with the next gluing increase the amount to 1.5 inches (35 mm). If the blade has been sealed, it may have to be lightly roughened with fine sandpaper to get the sheet to stick properly.
C. Wet Versus Dry Application
With some speed glues of the past, a number of players put the glue on when it was still wet. This is not recommended with the present solvent and adhesive systems as it reduces the spin component of the rubber. With the wet application, players may have to wait up to an hour before the normal spin component is achieved. This approach could also prevent the sheet from reaching the maximum dome, which can affect the control and feel of the rubber. For the present solvent and adhesive systems, best results appear to occur when the sheet is adhered when it is tacky but dry.
D. Putting the Rubber on the Blade Too Early
If a sheet is put on before it has fully expanded or domed, this can negatively affect the playing characteristics of the rubber. The speed/spin performance of the sheet will be reduced and the rubber may have a dead "cardboard" feel. This can occur for a number of reasons, including gluing the rubber in a cold environment, or not waiting long enough for the sheet to fully dome.
If for any reason the rubber is not playing up to normal standards and it is suspected that the sheet was put on without being fully domed, all is not lost. Continue to play with the racket, and after approximately twenty to forty minutes of play, remove the sheet and glue it on again. Playing with the rubber for this period of time activates the chemicals in the sponge and causes the sheet to dome. It is not unusual to see a significant increase in the dome size immediately after it is removed from the racket, compared to the way it was when first put on. When regluing the second time, the likely result is a second increase in dome size from even a small amount of glue. As a result, only a small amount of glue is needed on the rubber and the blade, i.e., just enough to cover both surfaces.
E. How Often to Reglue
How often to reglue depends to a large extent on the performance level desired. Many players will find that one regluing will last the length of a day-long tournament (assuming it is eight hours long). This is especially true if the racket was glued heavily the first time. However, regluing every three to four hours appears to provide the maximum effect. In a two-day tournament, the present solvent and adhesive systems will have a considerable residual effect from the first day to the second day. Therefore, less glue will be needed the second day to achieve the same performance as the first day. Some players have reported that the glue effect lasted up to forty-eight hours after regluing three times in a single day.
F. Performance Changes Over Time
The present solvent and adhesive systems were designed to have a constant performance for a long period of time. However, performance variation varies over time, at least to some extent, and the player should anticipate this occurrence to establish the timing of regluing for tournament play.
For the first half hour after regluing there will be an increase in speed with a lesser degree of spin increase. After approximately thirty minutes the spin/speed component will be balanced and should remain at this balance for the next few hours. This is the ideal time for tournament play. This period of time can be reduced by warming up with the racket while it is in the high speed mode. After approximately three to four hours, the speed component of the rubber will decrease (slightly to moderately depending on the conditions) while the spin component will remain high. Some players may find this performance balance more to their liking. For an early morning tournament match this state can be achieved by regluing the racket heavily the night before and putting it in a racket press.
If the reglued rubber does not have enough spin or speed, it also may be that the sheet was put on too wet. If this is suspected, continue play with the sheet for another forty minutes. If there is no improvement in performance reglue the sheet.
G. When to Remove the Rubber From the Blade
Typically, it is beneficial to remove the reglued rubber sheet immediately from the blade after finishing playing. The reason for this is that the expanded sheet wants to shrink and is prevented from doing so by the adhesive bond. This puts a great deal of stress on the sponge and can reduce the effective playing lifetime of the sponge and top sheet. Also, with time the adhesive bond becomes stronger. In some instances the sheet can be very difficult to remove. When removing a highly bonded sheet, it is best to slowly pull the sheet off the blade. For blades which have not been sealed or which have a rough face, the sheet should be pulled up in the direction of the grain so as not to pull out wood fibers. Do not try to rip the sheet off. This will prematurely age the stop sheet of the rubber.
H. Using a Racket Press
Table tennis racket presses are very useful for regluing for a number of reasons, including: (1) presses aid in the successful bonding of heavily curled or domed sheets by holding the sheet with even pressure on all points of the racket face; (2) presses extend the speed glue effect; and (3) presses help provide consistent regluing performance. When using a racket press cover sheets should always be placed over the rubber to protect its surface. Also, never over-tighten the press; light, even, constant pressure is all that is needed for most situations.
I. Removing Glue Build Up
After a number of regluings, the glue buildup may inhibit the speed glue effect. Also, glue build-up can be so great as to affect the weight balance of the racket. Glue buildup of up to six grams or more per sheet is not uncommon. If glue build-up is adversely affecting performance, the sheet can be discarded or an attempt can be made to remove the glue. Removing the glue is a very messy and time-consuming process and requires the use of powerful solvents. However, the solvent systems of the present invention solve this problem.
J. Using Speed Glue Solvent Systems
The speed glue solvent systems can be used once the sponge has been "primed" with three or four coats of adhesive system. To reglue using the solvent systems, follow approximately the same approach as discussed above except replace the adhesive systems with the solvent systems. The present speed glue solvent systems have several advantages compared to normal speed glue, including: (1) dramatically reducing the glue build-up on the sheet and greatly extending the life of the rubber sheet; (2) providing higher performance than can be achieved by increasing the solvent amounts above what is practical with normal speed glues; (3) the present solvent systems are more economical in terms of the amount needed to achieve a particular level of performance; and (4) sheets reglued with the present solvent systems can be used almost immediately.
Because the solvent systems have lower viscosities than the adhesive systems, a different approach is needed when applying the solvent systems to the "primed" sponge. Currently, the best results appear to occur by brushing onto the sponge enough fluid to completely cover a circle of about four to about five inches (100 to 125 mm) in diameter. Light brush strokes can be used to distribute the fluid evenly over the entire surface.
The first application should be allowed to dry before applying another layer of the solvent systems. This may take anywhere from two to ten minutes, depending on temperature and humidity conditions and the amount of fluid applied. If desired, apply the fluid several times, allowing the sheet to become dry between applications. Note that for each subsequent application a much smaller amount of the solvent systems will be adequate. Make sure that every area of the sponge is "wetted," and be especially careful with the edges of the sheet. A dry spot on the edge will not stick and the sheet may curl up from this point.
Several small applications of the solvent systems work better than one big application, as the first few applications open up the pores of the sponge for the later applications. The amount of fluid needed can be judged by the resultant dome increase from each application of the solvent systems. For the brave of heart go for the extreme dome by using repeated applications of solvent. But always allow each layer of the solvent systems to dry before proceeding to the next or the result may be a soggy, uneven solids layer that does not perform well.
An interesting effect is seen if one first dopes the sponge with pure D-limonene. After the sponge swells to the maximum (this takes approximately 20 to 30 minutes), a 50/50 cyclohexane/ethyl acetate mixture is then applied. Higher performance and longevity are seen when this approach is used than if one uses the three solvent blend by itself. However, the commercial viability of such a system is somewhat doubtful, as such an elaborate process is practical for only highly competitive or world class players who need every performance advantage possible.
http://www.tomveatch.com/tt/speed.glue. ... wtouseglue
VII. Speed Gluing Table Tennis Rackets
Experience has shown that to achieve the maximum performance from regluing, a fresh sheet of rubber needs to be "primed" before it can be reglued. This entails putting two or three thin layers of speed glue on the sponge prior to its use on the racket. Each of the layers should be allowed to dry completely before placing another layer on the sponge. After the final priming layer is dry, it is best to wait at least eight hours and preferably twenty-four hours before the sheet is ready for regluing and putting on a racket. One reason for this is that the glue solids (as opposed to the solvents, which evaporate), need a number of hours to develop a stable strong bond with the sponge. If one does not wait a long enough time for the solid layer to bond, the spin component of the rubber will be reduced and the sheet may not stick to the racket face securely.
A. Priming the Rubber for Regluing
To achieve the maximum performance from regluing, a fresh sheet of rubber needs to be "primed" before it can be re-glued. This entails putting two or three thin layers of speed glue on the sponge prior to its use on the racket. Each of the layers should be allowed to dry completely before placing another layer on the sponge. After the final priming layer is dry, it is best to wait at least 8 hours, and preferably 24 hours, before the sheet is ready for regluing and putting on a racket. One of the reasons for this is that the solids of the adhesive system (as opposed to the solvent, which evaporates), needs a number of hours to develop a stable, strong bond to the sponge. If used before the solid layer has bonded, the spin component of the rubber will be reduced and the sheet may not stick to the racket face securely.
One easy way to judge the amount of glue to place on the rubber is to pour an amount out onto the center of the sheet. The diameter of the circle tells the amount of glue being used very accurately. For priming sheets, a circle of glue of about 1.5 inches (35 mm) in diameter can be used for each priming. Another technique is to count the number of times a brush is dipped into a can. The diameter method is better, however, as it is easy to remember and judge.
B. Amount of Glue to Use on the Sponge
A major consideration for the player when deciding how much glue to apply is how much performance boost is required. To achieve a minimum effect, the diameter of glue applied should be at least 1.5 inches (35 mm). The rubber should dome up in a few minutes. The height of the dome depends on a number of factors, including: (1) the softer the sponge, the higher the dome; (2) the thinner the glue build-up, the higher the dome; (3) the thinner the sponge thickness, the higher the dome; and (4) the higher the air temperature, the higher the dome.
The height of the dome is a very good indicator of the potential performance of the sheet. However, a sheet does not always require a big dome to have a performance boost. With experience it is possible to judge from the dome size which effect is likely to occur from a particular amount of glue used. In some circumstances the amount of glue must be adjusted to achieve the same dome. For example, if the sheet has a large glue build-up, more glue may have to be applied than normal to achieve the same dome and therefore the same performance as in previous gluings. This is also true of gluing in cold temperature conditions.
There are a number of doming stages that a rubber sheet can go through, including: (1) a mild dome--having a height of approximately 1" (25 mm); (2) a medium dome--having a height of approximately 2" (50 mm); (3) a high dome, wherein the sheet develops heavy curl; and (4) an extreme dome, wherein the sheet curls up into a tube.
To achieve a big speed glue effect versus a mild effect more glue needs to be applied. However, instead of putting on a large amount of glue at one time, more than one application of glue should be applied, and then one must wait until the rubber has achieved its maximum dome after approximately five to seven minutes. If the dome is not sufficient, another layer of glue needs to be applied using a glue diameter of about 1.5 inches (35 mm) for each application. On sheets which already have a considerable glue build-up, maximum performance can be achieved by using the solvent systems alone, instead of the adhesive systems.
In order for the rubber sheet to stick properly on the blade, a fresh layer of glue needs to be applied on its face. The amount of glue needed depends on a number of factors, including: (1) whether or not the blade has been used before; (2) whether the face is rough or smooth; and (3) whether a sealer has been put on the face and, if so, the type of sealer employed.
For a previously used blade having an average roughness, start with a circle of glue about 1 inch (25 mm) in diameter. Brush the glue over the entire face evenly. If there are any dry spots cover them with glue, obtaining the glue by dipping the brush into the bottle. If it appears that edges might curl, cover the edges with a second application of glue by the dip method.
On a brand new blade, apply two thin even coats of glue. The first coat should be allowed to dry before applying the second coat. If the sheet does not sticking properly with a 1" (25 mm) circle of glue, then with the next gluing increase the amount to 1.5 inches (35 mm). If the blade has been sealed, it may have to be lightly roughened with fine sandpaper to get the sheet to stick properly.
C. Wet Versus Dry Application
With some speed glues of the past, a number of players put the glue on when it was still wet. This is not recommended with the present solvent and adhesive systems as it reduces the spin component of the rubber. With the wet application, players may have to wait up to an hour before the normal spin component is achieved. This approach could also prevent the sheet from reaching the maximum dome, which can affect the control and feel of the rubber. For the present solvent and adhesive systems, best results appear to occur when the sheet is adhered when it is tacky but dry.
D. Putting the Rubber on the Blade Too Early
If a sheet is put on before it has fully expanded or domed, this can negatively affect the playing characteristics of the rubber. The speed/spin performance of the sheet will be reduced and the rubber may have a dead "cardboard" feel. This can occur for a number of reasons, including gluing the rubber in a cold environment, or not waiting long enough for the sheet to fully dome.
If for any reason the rubber is not playing up to normal standards and it is suspected that the sheet was put on without being fully domed, all is not lost. Continue to play with the racket, and after approximately twenty to forty minutes of play, remove the sheet and glue it on again. Playing with the rubber for this period of time activates the chemicals in the sponge and causes the sheet to dome. It is not unusual to see a significant increase in the dome size immediately after it is removed from the racket, compared to the way it was when first put on. When regluing the second time, the likely result is a second increase in dome size from even a small amount of glue. As a result, only a small amount of glue is needed on the rubber and the blade, i.e., just enough to cover both surfaces.
E. How Often to Reglue
How often to reglue depends to a large extent on the performance level desired. Many players will find that one regluing will last the length of a day-long tournament (assuming it is eight hours long). This is especially true if the racket was glued heavily the first time. However, regluing every three to four hours appears to provide the maximum effect. In a two-day tournament, the present solvent and adhesive systems will have a considerable residual effect from the first day to the second day. Therefore, less glue will be needed the second day to achieve the same performance as the first day. Some players have reported that the glue effect lasted up to forty-eight hours after regluing three times in a single day.
F. Performance Changes Over Time
The present solvent and adhesive systems were designed to have a constant performance for a long period of time. However, performance variation varies over time, at least to some extent, and the player should anticipate this occurrence to establish the timing of regluing for tournament play.
For the first half hour after regluing there will be an increase in speed with a lesser degree of spin increase. After approximately thirty minutes the spin/speed component will be balanced and should remain at this balance for the next few hours. This is the ideal time for tournament play. This period of time can be reduced by warming up with the racket while it is in the high speed mode. After approximately three to four hours, the speed component of the rubber will decrease (slightly to moderately depending on the conditions) while the spin component will remain high. Some players may find this performance balance more to their liking. For an early morning tournament match this state can be achieved by regluing the racket heavily the night before and putting it in a racket press.
If the reglued rubber does not have enough spin or speed, it also may be that the sheet was put on too wet. If this is suspected, continue play with the sheet for another forty minutes. If there is no improvement in performance reglue the sheet.
G. When to Remove the Rubber From the Blade
Typically, it is beneficial to remove the reglued rubber sheet immediately from the blade after finishing playing. The reason for this is that the expanded sheet wants to shrink and is prevented from doing so by the adhesive bond. This puts a great deal of stress on the sponge and can reduce the effective playing lifetime of the sponge and top sheet. Also, with time the adhesive bond becomes stronger. In some instances the sheet can be very difficult to remove. When removing a highly bonded sheet, it is best to slowly pull the sheet off the blade. For blades which have not been sealed or which have a rough face, the sheet should be pulled up in the direction of the grain so as not to pull out wood fibers. Do not try to rip the sheet off. This will prematurely age the stop sheet of the rubber.
H. Using a Racket Press
Table tennis racket presses are very useful for regluing for a number of reasons, including: (1) presses aid in the successful bonding of heavily curled or domed sheets by holding the sheet with even pressure on all points of the racket face; (2) presses extend the speed glue effect; and (3) presses help provide consistent regluing performance. When using a racket press cover sheets should always be placed over the rubber to protect its surface. Also, never over-tighten the press; light, even, constant pressure is all that is needed for most situations.
I. Removing Glue Build Up
After a number of regluings, the glue buildup may inhibit the speed glue effect. Also, glue build-up can be so great as to affect the weight balance of the racket. Glue buildup of up to six grams or more per sheet is not uncommon. If glue build-up is adversely affecting performance, the sheet can be discarded or an attempt can be made to remove the glue. Removing the glue is a very messy and time-consuming process and requires the use of powerful solvents. However, the solvent systems of the present invention solve this problem.
J. Using Speed Glue Solvent Systems
The speed glue solvent systems can be used once the sponge has been "primed" with three or four coats of adhesive system. To reglue using the solvent systems, follow approximately the same approach as discussed above except replace the adhesive systems with the solvent systems. The present speed glue solvent systems have several advantages compared to normal speed glue, including: (1) dramatically reducing the glue build-up on the sheet and greatly extending the life of the rubber sheet; (2) providing higher performance than can be achieved by increasing the solvent amounts above what is practical with normal speed glues; (3) the present solvent systems are more economical in terms of the amount needed to achieve a particular level of performance; and (4) sheets reglued with the present solvent systems can be used almost immediately.
Because the solvent systems have lower viscosities than the adhesive systems, a different approach is needed when applying the solvent systems to the "primed" sponge. Currently, the best results appear to occur by brushing onto the sponge enough fluid to completely cover a circle of about four to about five inches (100 to 125 mm) in diameter. Light brush strokes can be used to distribute the fluid evenly over the entire surface.
The first application should be allowed to dry before applying another layer of the solvent systems. This may take anywhere from two to ten minutes, depending on temperature and humidity conditions and the amount of fluid applied. If desired, apply the fluid several times, allowing the sheet to become dry between applications. Note that for each subsequent application a much smaller amount of the solvent systems will be adequate. Make sure that every area of the sponge is "wetted," and be especially careful with the edges of the sheet. A dry spot on the edge will not stick and the sheet may curl up from this point.
Several small applications of the solvent systems work better than one big application, as the first few applications open up the pores of the sponge for the later applications. The amount of fluid needed can be judged by the resultant dome increase from each application of the solvent systems. For the brave of heart go for the extreme dome by using repeated applications of solvent. But always allow each layer of the solvent systems to dry before proceeding to the next or the result may be a soggy, uneven solids layer that does not perform well.
An interesting effect is seen if one first dopes the sponge with pure D-limonene. After the sponge swells to the maximum (this takes approximately 20 to 30 minutes), a 50/50 cyclohexane/ethyl acetate mixture is then applied. Higher performance and longevity are seen when this approach is used than if one uses the three solvent blend by itself. However, the commercial viability of such a system is somewhat doubtful, as such an elaborate process is practical for only highly competitive or world class players who need every performance advantage possible.
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