I've been thinking about this subject for almost a month, now. **insert scratching of head, here** I have read (and heard) a lot about how the materials and design of the frame and shaft can affect the way a racquet plays, and how it gives feedback to the player. I kept thinking that these characteristics should be affect by every part of the racquet, especially the parts that hold the string or come in contact with the string. I don't think there have been any major changes in either the technology (materials?) or design of grommets ever since they came into being. With the availability of new composites and space-age materials, I wonder if there is a case for reviewing the grommets currently in use by all major manufacturers? I'm not a techie so you guys will have to excuse my "non-technical" chatter. Won't grommets be responsible at elast in part for a "damping" effect on the strings? If a "better" grommet (by design and material) were to be used, which would absorb less of the energy transferred from the player to the strings, would that not be desirable? Also, such a "better" grommet would provide more tactile feedback as well. Your thoughts?
I think a more correct analogy may be: "will the design of the shock absorbers of a car, make the car ride corners better, make the car safer, make for smoother handling on rough roads?"
Thts a Good one!I wasn't making an analogy, I was making a point. I think to know the answer, one will need to find out exactly how much energy is loss via grommets ? Even if it does, is the amount significant? p/s if yonex ppl are here, u just gave them another gimmick to tempt us with newer models in near future. Hahaha.
Coming soon: New Yonex Hyperspace Grommet - this high-technology grommet contains, within its familiar iconic cylindrical shape, special nanohyperspace(NHS). The patented NHS allows string to actually pass from one side to the other. So advanced is this NHS (formerly called a hole) that it can also pass light, sound, and the smell of fresh apple pie. Introductory sale price: [how much you got?]
Not hawking anything new, cobalt. The same 'space' technology has been used in the centre of round pastries at Dunkin' Donuts for years. Strangely,even their empty spaces somehow seem to contain 50 calories each. -- To get back to your original question, grommets have gone through plenty of changes over the years. From drilled holes in wooden rackets to cylindrical plastic inserts to these double grommets at the throat and the grommet strips you can get for certain rackets. Not to mention the myriad of grommet hole patterns. The benefits are ease of stringing and reduction of string fraying. But does it actually help the racket performance? You need the big brains of BC to weigh in. There must be something on grommets somewhere in BC.... did you do a search?
I did search for some more info on grommets on BC, but nothing of substance could I find... Er, I was referring to the other Hawking earlier... but point taken...
well, let's list out something that people have done: - good ole dual pass round grommet - reducing single use grommet to thinner diameter - flared grommet on the inner frame side - thin grommet head which allow string to hug the frame - slightly elongated grommet heads (in Armortec series) - bridged grommet with curved bridge (2 holes) - multiple grommet stripes - going without grommet all together (Prince, Babolat) - softer grommet on strategic locations (usually middle strings) did i miss anything?
To the OP, hope we will not be treading into sink holes and worm holes or the final frontier, which is space instead of purely tackling plain ol' grommets. I'd like titanium (I know, I know, nothing new about the material...) mix with some kind of hard plastic for a grommet (the kind you find in armaments). That way, no one's ever gonna need grommet change before the frame collapses.
What's to say grommets aren't the final frontier in the racquets racket? (pun very intended! ) Think about the number of times our precious strings are forced to come in contact with those little plastic thingies, and how those thingies absorb or redirect or deflect some part of the energy on contact. but how much do you reckon it would take off your paycheque? Here's what I found: PEBA. Excerpts from Wikipedia: http://en.wikipedia.org/wiki/Polyether_block_amide "Polyether block amide or PEBA is a high performance thermoplastic elastomer. "...PEBA is found in the sports equipment market: for damping system components ... "...It is used in various other sports applications such as racquet grommets and golf balls." Apparently, some manufacturers also used teflon coating for friction reduction to allow for more efficient energy transfer.
Dunlop had come up with a "Biomimetic" racquet that also featured "AFG" or Anti-Friction Grommet design that minimizes string contact with the grommets. However, I believe this is only being used in their tennis racquets. Read below: "The 3Dom (rhymes with freedom) grommet system is a set of green pods made of material that is significantly softer than regular grommet material. The soft pods encase Anti-Friction Grommets (see below) and perform a similar function to cartilage surrounding joints; they provide padding while at the same time allowing greater freedom of movement for the strings. By allowing the strings to move in and out and left and right, more recoil is created giving shots additional power. The 3Dom system also serves a dual purpose of dampening any string vibration, making the racket easier on your arm at impact. "Anti-Friction Grommets (AFG) make up the second part of the 700’s grommet system. AFG allows the strings greater freedom of movement by minimizing their contact points with the grommet itself. This Biomimetic concept is based on the sandfish skink, an animal which has the ability to ‘swim’ through sand due to the formation of its miniature scales. Similarly, the AFG grommet system comprises a series of small ridges in each grommet designed so the string comes into contact with the ridges, rather than the entire grommet bed as in other rackets. By solely touching the ridges, string/grommet contact is significantly reduced, resulting in more string movement and greater power and spin for the player."
Interesting topic. We have to understand what function the grommets serve. In addition to holding the strings in the frame and transferring force and feel from the hand to bird and vice versa, we must not forget that the most important function of grommets is to protect the frame holes from disintegrating under the pressure of the strings. Especially during a hard hit eg smash. As such, from a warantee and durability point of view, manufacturers are bound to design grommets with this foremost in mind in regards to materials, structure, and placement. Grommets are designed to partially deform and give way slightly in order to even out the forces of te strings in order to protect the frame. IMHO of course.
Yonex had a pretty good idea with the MP embedded grommet/hole system where IMO, the force vectors were not so tangential where the string reached the frame.This would to my mind, allow for higher "flow" of force through the strigbed. Why did they discontinue this? Anyone know? Did it affect structural integrity?
IIRC, for the frame to hold up against the pressure from the string touching it at those points, the frame had to be made of very high [ultra high] modulus graphite which is very strong and stiff but unfortunately quite brittle. That is why when the MP100 was in its hey day, a lot of users (I believe the not so "professional" ones though) were breaking the racquets from mishits and off centre shots and were constantly complaining about how fragile the racquet is. This is also including the other high end MP racquets.
...hence, MP 99 is much more highly regarded than MP 100. Maybe the colour yellow is just better than red in certain respect?
Are you a designer for (not from, but for) Dunlop? AFG and 3Dom are like peas in the pod (with all the pun intentions intended).
those guys wouldn't let me near their front door if they had the sense! BTW, "AFG concept is based on the sandfish skink, an animal which has the ability etc etc..." Sandfish... Sandtrout.... Arrakis... Winner!
