Back to Forum
Page 1 of 3 123 LastLast
Results 1 to 20 of 46
  1. Gozo is offline
    says May the Spin be with you!
     
    Advanced TTD Member 247 389
    Gozo's Avatar
    Gozo is offline
    says May the Spin be with you!
     
    Advanced TTD Member 389 247
    #1

    Tackiness versus grippiness

    As per title,

    Grippiness versus Tackiness, which is a better option to generate spin.

    Does tacky grippy rubber exist? If yes, technically should be able to produce super massive awesome spin right?

    P/S Mod, if similar thread exist kindly assist to merge. Thank you.

  2. SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 892 1,386
    SFF_lib's Avatar
    SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 1,386 892
    #2
    Quote Originally Posted by Gozo
    As per title,

    Grippiness versus Tackiness, which is a better option to generate spin.

    Does tacky grippy rubber exist? If yes, technically should be able to produce super massive awesome spin right?

    P/S Mod, if similar thread exist kindly assist to merge. Thank you.
    Yes H3, especially boosted one is both tacky and grippy.

    I am sure most understand what tackiness is.

    Grippiness generates spin by allowing the ball to sink into the topsheet and sponge. The repulsive force spins the ball.

    If you have intermediate level of technique, you will generate spin from H3 by the tackiness and a bit of grippiness.

    Professionals like FZD can sink the ball all the way into a 42 degree H3. So you get a crazy spin from both the tackiness and grippiness of the rubber.

    That’s why even club level players can generate more spin with a 39 degree H3 than a D05. To be fair D05 slightly tacky and more grippy than T05

  3. Kuba Hajto is offline
    says Equipment matters a lot to scrubs who can't make minor adjustments to their stroke.
     
    Elite TTD Member 632 1,479
    K
    Kuba Hajto is offline
    says Equipment matters a lot to scrubs who can't make minor adjustments to their stroke.
     
    Elite TTD Member 1,479 632
    #3
    Quote Originally Posted by SFF_lib
    Yes H3, especially boosted one is both tacky and grippy.

    I am sure most understand what tackiness is.

    Grippiness generates spin by allowing the ball to sink into the topsheet and sponge. The repulsive force spins the ball.

    If you have intermediate level of technique, you will generate spin from H3 by the tackiness and a bit of grippiness.

    Professionals like FZD can sink the ball all the way into a 42 degree H3. So you get a crazy spin from both the tackiness and grippiness of the rubber.

    That’s why even club level players can generate more spin with a 39 degree H3 than a D05. To be fair D05 slightly tacky and more grippy than T05

    I may be crazy but I think there are slight differences between Commercial and Prov+ H3 top sheet (and Battle 2 in fact as well). Commercial H3, Bloom Spin, Battle 2 commercial, and Jupiter 2 among others are basically icy when they are moist and cold (imagine playing in winter is not so well heated room or in a basement in general). They are stupidly hard to get the grip on. In my opinion, Prov+ are very often less tacky but a little more grippy, and they are not as garbage as those conditions.

    Having tackiness helps a bunch with the short game as well as produces stupid amounts of spin.

    I think it actually the best when you have a tacky topsheet, and elastic enough to grip the ball. This might sound like chasing a golden unicorn, but that actually is just pesky illegal boosted tacky rubber.

    Offtopic: I miss tackiness so much 😭 I will probably get as close to identical blase as possible and just have a second almost identical setup with the only difference being tacky rubber on FH.

    The Following User Likes Kuba Hajto's Post:

    latej

    WTB Butterfly Ovtcharov and Vodak Horejsi ALC PM me if you want to sell one.

  4. igorponger is offline
    This user has no status.
     
    Senior TTD Member 190 643
    igorponger's Avatar
    igorponger is offline
    This user has no status.
     
    Senior TTD Member 643 190

    User Info Menu


    Jan 2012
    Former Soviet Union
    643
    190
    910
    Read 0 Reviews
    #4
    PLAIN GRIPPY RUBBER WOULD PLAY MORE BOUNCY AND SPINNY as follows from Tiefenbacher's laboratorian investigations.
    German engineer, Mr.Tiefenbacher answered this question back in 1990. He had made practical experiments using German and Chinese rubbers. German's came out more speedy and spinny at real play. The physics behind is that it will take a greater amount of energy for the ball to take off from the Chinese tacky rubber surface.

    Be happy.
    Last edited by igorponger; 11-06-2021 at 03:46 PM.

  5. Kuba Hajto is offline
    says Equipment matters a lot to scrubs who can't make minor adjustments to their stroke.
     
    Elite TTD Member 632 1,479
    K
    Kuba Hajto is offline
    says Equipment matters a lot to scrubs who can't make minor adjustments to their stroke.
     
    Elite TTD Member 1,479 632
    #5
    Quote Originally Posted by igorponger
    PLAIN GRIPPY RUBBER WOULD PLAY MORE BOUNCY AND SPINNY as follows from Tiefenbacher's laboratorian investigations.
    German engineer, Mr.Tiefenbacher answered this question back in 1990. He had made practical experiments using German and Chinese rubbers. German's came out more speedy and spinny at real play. The physics behind is that it will take a greater amount of energy for the ball to take off from the Chinese tacky rubber surface.

    Be happy.

    I know that you are just trolling, but:


    • Please provide a link to that study
    • Isn't 21 years a lot in terms of technology, even in a rather slow-progressing TT domain?
    WTB Butterfly Ovtcharov and Vodak Horejsi ALC PM me if you want to sell one.

  6. bzing is offline
    This user has no status.
     
    Advanced TTD Member 142 455
    B
    bzing is offline
    This user has no status.
     
    Advanced TTD Member 455 142

    User Info Menu


    Jul 2012
    Great Britain
    455
    142
    824
    Read 0 Reviews
    #6
    I feel like everytime I smash the ball using the H3, the opponent almost never gets it back. And technically when I smash it the ball does not have any more speed or mechanical spin on the ball for that matter when compared to smashing the ball using a grippy rubber.

    Tacky rubber seem to pack a lot more velocity into the ball than any grippy rubber does, it's why despite the ball may not be travelling faster or have a great mechanical spin, but it makes it harder to return the ball if the ball is struck with a good clean contact (hit-brush kind of loop) where a sufficient friction is applied.

  7. JustANoob is offline
    This user has no status.
     
    Established TTD Member 70 153
    J
    JustANoob is offline
    This user has no status.
     
    Established TTD Member 153 70
    #7
    Quote Originally Posted by igorponger
    PLAIN GRIPPY RUBBER WOULD PLAY MORE BOUNCY AND SPINNY as follows from Tiefenbacher's laboratorian investigations.
    German engineer, Mr.Tiefenbacher answered this question back in 1990. He had made practical experiments using German and Chinese rubbers. German's came out more speedy and spinny at real play. The physics behind is that it will take a greater amount of energy for the ball to take off from the Chinese tacky rubber surface.

    Be happy.

    But did he boost tho ?

    The Following User Likes JustANoob's Post:

    latej


  8. TTOmar is offline
    This user has no status.
     
    TTD Member 12 57
    TTOmar's Avatar
    TTOmar is offline
    This user has no status.
     
    TTD Member 57 12
    #8
    I can say Yinhe Apollo 5 featuring sort of both tackiness and grippiness depends on which style you hit the ball, it has bounciness of hard grippy german rubbers on flat hit, has tackiness on passive block and brush loop. It is a very technical rubber which wrong timing or stance on attacking generates unforced errors.

  9. Dominikk85 is offline
    This user has no status.
     
    Advanced TTD Member 110 256
    D
    Dominikk85 is offline
    This user has no status.
     
    Advanced TTD Member 256 110

    User Info Menu


    Jul 2017
    Germany
    256
    110
    232
    Read 0 Reviews
    #9
    Quote Originally Posted by bzing
    I feel like everytime I smash the ball using the H3, the opponent almost never gets it back. And technically when I smash it the ball does not have any more speed or mechanical spin on the ball for that matter when compared to smashing the ball using a grippy rubber.

    Tacky rubber seem to pack a lot more velocity into the ball than any grippy rubber does, it's why despite the ball may not be travelling faster or have a great mechanical spin, but it makes it harder to return the ball if the ball is struck with a good clean contact (hit-brush kind of loop) where a sufficient friction is applied.

    Not sure that is true, I always heard that grippy is faster on straight smashes and drives and and tacky is better for spin.

    In fact some Chinese players twiddle from their tacky h3 forehand rubber to their grippy tenergy to hit forehand smash against high lobs.

    The Chinese Euro thing gets a bit mixed up though, non chinese companies start to create tacky rubbers like dignics 09 and Chinese companies start to develope grippy rubbers like palio ak47.

    I think tacky top sheet with tensor sponge like dignics 09c might be about the best.

    I wonder when Chinese companies start producing rubbers with h3 like top sheet with tensor like fast sponges
    Last edited by Dominikk85; 11-06-2021 at 05:08 PM.

  10. brokenball is offline
    This user has no status.
     
    Elite TTD Member 467 1,004
    B
    brokenball is offline
    This user has no status.
     
    Elite TTD Member 1,004 467

    User Info Menu

    #10
    Quote Originally Posted by igorponger
    PLAIN GRIPPY RUBBER WOULD PLAY MORE BOUNCY AND SPINNY as follows from Tiefenbacher's laboratorian investigations.
    German engineer, Mr.Tiefenbacher answered this question back in 1990. He had made practical experiments using German and Chinese rubbers. German's came out more speedy and spinny at real play. The physics behind is that it will take a greater amount of energy for the ball to take off from the Chinese tacky rubber surface.

    Be happy.
    https://deltamotion.com/peter/TableT...-%20Impact.pdf
    Great! You read it. You are the second one besides me to have read it. However, I don't see where Tieffenbacher said that tacky rubbers were more bouncy. Where did Tieffenbacher say Tacky rubbers were more bouncy? The bouncy part is due to the foam rubber. The tack part is due to the top sheet. See section C of page 9.

    The "tack" or "stickiness" of the rubber will hold a TT ball on the bottom of the paddle for many seconds. However some speed is lost because some extra force is required to break away from the rubber.

    BTW, I understand what you guys are saying when you use terms such as tacky. Some companies use the term "mechanical" grip.
    There are NO equations that use these terms.
    There is a coefficient of friction which is quite high for normal rubbers. This means the tangential force can be as high as some factor times the perpendicular force. It should be obvious that when the ball just touches the rubber there is no force between the ball and the rubber so there can be NO tangential force. Tacky rubbers will grip even when the force is light like fly paper. However, like fly paper it will inhibit the ball from leaving too.

    Quote Originally Posted by Kuba Hajto
    I know that you are just trolling, but:
    He isn't

    Please provide a link to that study
    I did above.

    Isn't 21 years a lot in terms of technology, even in a rather slow-progressing TT domain?
    What you are suggesting is the Newton's 3 laws of motion don't apply because technology has changed.
    Physics doesn't change. The coefficients of restitution might be a little higher and the ball is certainly bigger and heavier but the basics still apply.

    The Following User Likes brokenball's Post:

    UpSideDownCarl


  11. Zwill is offline
    This user has no status.
     
    Established TTD Member 65 136
    Zwill's Avatar
    Zwill is offline
    This user has no status.
     
    Established TTD Member 136 65

    User Info Menu


    Oct 2018
    Hungary
    136
    65
    70
    Read 0 Reviews
    #11
    Quote Originally Posted by igorponger
    PLAIN GRIPPY RUBBER WOULD PLAY MORE BOUNCY AND SPINNY as follows from Tiefenbacher's laboratorian investigations.German engineer, Mr.Tiefenbacher answered this question back in 1990. He had made practical experiments using German and Chinese rubbers. German's came out more speedy and spinny at real play. The physics behind is that it will take a greater amount of energy for the ball to take off from the Chinese tacky rubber surface.Be happy.

    Actually I'm with igorponger on this one may it sound as crazy as it does. Tacky rubbers like H3 are indeed spinny, but I feel like the stickiness is not only holding back the speed but the spin as well.

    I am a huge sticky rubber fan, H3 blue sponge is probably thebest rubber out there for me, but not because it is the most spinny.

    That being said the conditions have to be determined too, humid, cold, hot, ball is new or old? Tacky rubbers are much more consistent with new balls and well used balls that are shiny. The stickiness grabs the shiny balls very well, while grippy rubbes might slip.

    This is not so black and white as forums tend ot make it to be and I don't see much discussion about these conditions.

    The Following User Likes Zwill's Post:

    UpSideDownCarl

    Last edited by Zwill; 11-06-2021 at 09:09 PM.

  12. IB66 is offline
    This user has no status.
     
    Senior TTD Member 521 997
    I
    IB66 is offline
    This user has no status.
     
    Senior TTD Member 997 521
    #12
    Quote Originally Posted by Kuba Hajto

    I know that you are just trolling, but:


    • Please provide a link to that study
    • Isn't 21 years a lot in terms of technology, even in a rather slow-progressing TT domain?

    There’s a study Brokenball posted, you can also find it on the ITTF website, it was about dwell time, etc.
    the study was Undertaken by a French institute for ITTF, they also did a study regarding bounce from tables.
    The report showed that grippy Euro / Jap rubbers can produce more spin. However I thought there were some results not included on one of the tables, which for me casts a little doubt on the study.
    also the physics behind it is too much for my brain to fully understand!!!!
    another point is that I think the study was commissioned by ITTF’s equipment and technology department, could be wrong on this though, anyway the head of this department could be seen to be very biased in favour of ESN, because she worked for them for a long time!!
    of course this is purely speculation.
    Anyway, once a person is linked to a company, I just feel they will be biased towards that companies products. In the same way a sponsored pro will be.
    This study was undertaken a while ago as well.

    The other study on bounce of balls on tables and the varying finishes they have is a very valid one, I think the ITTF are looking in to compressing the range of bounce and spin so that the differences in how different manufacturers tables play is standardised to a certain extent.


  13. brokenball is offline
    This user has no status.
     
    Elite TTD Member 467 1,004
    B
    brokenball is offline
    This user has no status.
     
    Elite TTD Member 1,004 467

    User Info Menu

    #13
    Quote Originally Posted by IB66
    The other study on bounce of balls on tables and the varying finishes they have is a very valid one, I think the ITTF are looking in to compressing the range of bounce and spin so that the differences in how different manufacturers tables play is standardised to a certain extent.
    There is already a specification for the COR of a ball bouncing off a steel plate from 30cm high. The unfortunate thing is that the COR changes as a function of impact speed according to the Tiffenbacher studies. This means the balls may be much different if bouncing at different speeds.

    The bounce off of tables is harder to define. First you must look at how the tables tops are made. Most of the time they are made by compressing wood pieces with a glue. This assumes the woods pieces are distributed evenly and the glue is applied evenly before compressing. I find it hard to believe this can be done within a few percent of variance in the finished density of the wood.

    The table tops are also varying between manufacturers. This affects the bounce after impact. I am not a fan of table tops that are slick as it doesn't reward loopers enough. A real loop will bounce out low and fast because there is some friction between the ball and table.

  14. IB66 is offline
    This user has no status.
     
    Senior TTD Member 521 997
    I
    IB66 is offline
    This user has no status.
     
    Senior TTD Member 997 521
    #14
    Quote Originally Posted by brokenball
    There is already a specification for the COR of a ball bouncing off a steel plate from 30cm high. The unfortunate thing is that the COR changes as a function of impact speed according to the Tiffenbacher studies. This means the balls may be much different if bouncing at different speeds.

    The bounce off of tables is harder to define. First you must look at how the tables tops are made. Most of the time they are made by compressing wood pieces with a glue. This assumes the woods pieces are distributed evenly and the glue is applied evenly before compressing. I find it hard to believe this can be done within a few percent of variance in the finished density of the wood.

    The table tops are also varying between manufacturers. This affects the bounce after impact. I am not a fan of table tops that are slick as it doesn't reward loopers enough. A real loop will bounce out low and fast because there is some friction between the ball and table.

    Yeah, the tables with higher friction attributes cause the ball to react more on impact but reduce the amount of spin remaining on the ball after impact with the table. The ‘slippery’ tables when the ball can ‘skid’ through don’t remove as much spin from the ball, so you have more residual spin to deal with.
    Table top thickness, material type, and paint finish are factors that all contribute to how the ball reacts after impact with the table.
    the above is sort of hard to get a grip on!!!
    when I play on a glossy slippery table I feel that I’m not spinning the ball well, because you don’t ‘see’ as much reaction when the ball bounces, but the spin is still there.
    I also think that possibly the ITTF want to increase the appeal of table tennis, not make it easier per say, but a better sport for spectators. Bigger balls, trying to reduce spin levels, maybe trying to slow the game down helping to create longer exciting rallies.
    the type of table surface and properties will play quite a big part in this.

    Moving back to the tackiness/grippyness subject, we all get obsessed about max this and max that!!!
    a ball spinning at 6000 rpm and one spinning at 6500 rpm can we really tell the difference during play??? How much does that additional 500rpm actually make??
    I think that many rubbers produce heavy heavy spin be they grippy or tacky, it’s more a case of technique of the individual that plays the biggest part.

    On the other hand if you put the ‘control’ into the hands of completely similar robots playing against each other that have the same ‘limits’ but differing rubbers, then maybe you would ‘see’ the difference that the top sheets actually make. According to the study quoted the robot using the grippy rubber should produce some more spin and speed. At least I hope I’ve got this right!!!


  15. SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 892 1,386
    SFF_lib's Avatar
    SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 1,386 892
    #15
    Quote Originally Posted by Kuba Hajto

    I may be crazy but I think there are slight differences between Commercial and Prov+ H3 top sheet (and Battle 2 in fact as well). Commercial H3, Bloom Spin, Battle 2 commercial, and Jupiter 2 among others are basically icy when they are moist and cold (imagine playing in winter is not so well heated room or in a basement in general). They are stupidly hard to get the grip on. In my opinion, Prov+ are very often less tacky but a little more grippy, and they are not as garbage as those conditions.

    Having tackiness helps a bunch with the short game as well as produces stupid amounts of spin.

    I think it actually the best when you have a tacky topsheet, and elastic enough to grip the ball. This might sound like chasing a golden unicorn, but that actually is just pesky illegal boosted tacky rubber.

    Offtopic: I miss tackiness so much I will probably get as close to identical blase as possible and just have a second almost identical setup with the only difference being tacky rubber on FH.

    The sponge of H3 prov is more lively and has higher QC. Commercial H3 is fine. But in my experience out of 5 commercial H3 you might have 3 different feels. But prov H3 is very consistent

  16. SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 892 1,386
    SFF_lib's Avatar
    SFF_lib is online now
    This user has no status.
     
    Elite TTD Member 1,386 892
    #16
    Quote Originally Posted by IB66

    Yeah, the tables with higher friction attributes cause the ball to react more on impact but reduce the amount of spin remaining on the ball after impact with the table. The ‘slippery’ tables when the ball can ‘skid’ through don’t remove as much spin from the ball, so you have more residual spin to deal with.
    Table top thickness, material type, and paint finish are factors that all contribute to how the ball reacts after impact with the table.
    the above is sort of hard to get a grip on!!!
    when I play on a glossy slippery table I feel that I’m not spinning the ball well, because you don’t ‘see’ as much reaction when the ball bounces, but the spin is still there.
    I also think that possibly the ITTF want to increase the appeal of table tennis, not make it easier per say, but a better sport for spectators. Bigger balls, trying to reduce spin levels, maybe trying to slow the game down helping to create longer exciting rallies.
    the type of table surface and properties will play quite a big part in this.

    Moving back to the tackiness/grippyness subject, we all get obsessed about max this and max that!!!
    a ball spinning at 6000 rpm and one spinning at 6500 rpm can we really tell the difference during play??? How much does that additional 500rpm actually make??
    I think that many rubbers produce heavy heavy spin be they grippy or tacky, it’s more a case of technique of the individual that plays the biggest part.

    On the other hand if you put the ‘control’ into the hands of completely similar robots playing against each other that have the same ‘limits’ but differing rubbers, then maybe you would ‘see’ the difference that the top sheets actually make. According to the study quoted the robot using the grippy rubber should produce some more spin and speed. At least I hope I’ve got this right!!!

    Eye opening thank you.

    I’ve never paid attention to the effects of the table tbh. Our club has the privilege to acquire a few Olympic standard tables for the upcoming Oceania championship. But we don’t get to play it yet

  17. Tango K is offline
    This user has no status.
     
    Advanced TTD Member 305 469
    T
    Tango K is offline
    This user has no status.
     
    Advanced TTD Member 469 305

    User Info Menu


    Jan 2020
    UK
    469
    305
    992
    Read 0 Reviews
    #17
    There is this simple thing that, for some reasons, is so confusing when we all try to model things and forget what the model is for.

    from physics perspective. The ball hits you at -V is the same as you hit the ball at V. From practical perspective, there is a huge difference between ball comes at -B1 and you hit at H1 versus ball comes at -B2 and you hit at H2, even if B1+H1 = B2+H2. The ball you deal with is different andthe power you put on is absolutely different. If you sorta get this you’ll kinda see how tackyness works. It kills B, allowing you control your H better, whether it is to shrink the ball more IN YOUR WAY for your own spin+power, or to make your slow thin brush so dead that only spin is left.

    These researches don’t take into account that nobody swings a tacky rubner the same way as they do a bouncy one. (Because it wasn’t their purposes) No matter how hard you try to swing the same, you wont. We automatically adjust.

    think about your forehand swing. So much is put into body rotation for so little actual physics’ energy going into the ball. You have to put a stroke into perspective of human action, not a precise instant burst into the correct contact. Or you can just become Thanos and flick your wrist precisely and the spin and speed will be wonder!

  18. brokenball is offline
    This user has no status.
     
    Elite TTD Member 467 1,004
    B
    brokenball is offline
    This user has no status.
     
    Elite TTD Member 1,004 467

    User Info Menu

    #18
    So, it seems everyone measures "tackiness" by seeing how long a ball will stick to the bottoms side of a horizontal paddle but "tackiness" only seems to last a few seconds IF the rubber is clean.
    "grip" by any other name is just the coefficient for friction. This can be measured.
    Cut 2 TT balls in two perfect halves.
    Glue 3 of the haves to one side of a thin sheet of card board in a triangle pattern. Call this the test widget or just widget.
    Attach a small spring scale to the card board of the widget. It is probably best to do this indirectly by using a thread to connect the card board to the spring scale. This way the spring scale will not add weight to the widget.
    Weigh the widget as accurate as possible. I can measure down to 0.01 grams..
    Now place the on horizontal rubber and pull on the spring scale until the widget starts to move. The force just before the widget moves should be divided by the force due to weight. of the the widget. This will provide the coefficient of friction for the weight of the widget.
    Do this again only this time put some thing small on the widget to increase the weight and measure the weight.
    Do the drag test again and plot the maximum force necessary to pull the widget.
    Keep adding weights and plotting the results.
    you now will have a graph or plot of the coefficient of friction vs force due to weight.
    Note, as one starts to pull on the widget using the spring scale the force will increase until it breaks free. It is the maximum force that you want.

    Now try on an different rubbers and compare. try it on a tacky rubber too.

    For extra credit, the card board of the widget will be lower as more force is applied. Use a micrometer to measure how much the rubber is depressed as a function of extra weight. This will give you an idea of how soft or hard the rubber really is. It will be much more useful that a durometer reading. Eventually you will add so much weight that the rubber no longer compresses. This is where the rubber effectively "bottoms out". A good micrometer may be expensive. Spring scales are cheap.

    I bet no one has a clue as to how much force the ball and paddle exert on each other as a function of impact speeds.. Find out. Do the math.
    If no one does the TT forums will be clueless until someone does.

    For more credit, how much does a TT blade deflect as a function of force?





  19. lodro is online now
    says TT-CLOWN, old git
     
    Senior TTD Member 280 793
    L
    lodro is online now
    says TT-CLOWN, old git
     
    Senior TTD Member 793 280
    #19
    Quote Originally Posted by brokenball
    So, it seems everyone measures "tackiness" by seeing how long a ball will stick to the bottoms side of a horizontal paddle but "tackiness" only seems to last a few seconds IF the rubber is clean. "grip" by any other name is just the coefficient for friction. This can be measured. Cut 2 TT balls in two perfect halves. Glue 3 of the haves to one side of a thin sheet of card board in a triangle pattern. Call this the test widget or just widget. Attach a small spring scale to the card board of the widget. It is probably best to do this indirectly by using a thread to connect the card board to the spring scale. This way the spring scale will not add weight to the widget. Weigh the widget as accurate as possible. I can measure down to 0.01 grams.. Now place the on horizontal rubber and pull on the spring scale until the widget starts to move. The force just before the widget moves should be divided by the force due to weight. of the the widget. This will provide the coefficient of friction for the weight of the widget. Do this again only this time put some thing small on the widget to increase the weight and measure the weight. Do the drag test again and plot the maximum force necessary to pull the widget. Keep adding weights and plotting the results. you now will have a graph or plot of the coefficient of friction vs force due to weight. Note, as one starts to pull on the widget using the spring scale the force will increase until it breaks free. It is the maximum force that you want. Now try on an different rubbers and compare. try it on a tacky rubber too. For extra credit, the card board of the widget will be lower as more force is applied. Use a micrometer to measure how much the rubber is depressed as a function of extra weight. This will give you an idea of how soft or hard the rubber really is. It will be much more useful that a durometer reading. Eventually you will add so much weight that the rubber no longer compresses. This is where the rubber effectively "bottoms out". A good micrometer may be expensive. Spring scales are cheap. I bet no one has a clue as to how much force the ball and paddle exert on each other as a function of impact speeds.. Find out. Do the math. If no one does the TT forums will be clueless until someone does. For more credit, how much does a TT blade deflect as a function of force?

    thanks BB as usual, very exact and methodical. I just had my Sunday afternoon session at the club. Played some singles, some doubles and some time with the coach, sweated a lot; good fun. Later, when i will probably be in a wheelchair, I might have time for the experiments you suggest. In the meantime I am having too much fun just playing TT and be with friends 😂

    Last edited by lodro; 11-07-2021 at 05:27 AM.

  20. IB66 is offline
    This user has no status.
     
    Senior TTD Member 521 997
    I
    IB66 is offline
    This user has no status.
     
    Senior TTD Member 997 521
    #20
    Quote Originally Posted by SFF_lib
    Eye opening thank you.

    I’ve never paid attention to the effects of the table tbh. Our club has the privilege to acquire a few Olympic standard tables for the upcoming Oceania championship. But we don’t get to play it yet

    Some of the glossy tables can mess with your head!!!! The table I have at home is pretty grippy, so when I try and practice ghost or heavy back spin serves, the ball holds up nicely then spins back into the net, the tables at the club I train at, still have some grip, but it’s less than my home table, it’s harder to get the ball to return into the net.
    At first I thought I was not performing the serve correctly, but it’s the table not the player in this instance. .

    The Following User Likes IB66's Post:

    lodro


Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Create a new Topic:
Title is required.