Discussion in 'Strings' started by mikeler, May 9, 2013.
Clearly his strings are not snapping back in this photo:
How can you say that his strings aren't snapping back, just by looking at that picture?
think Nadal uses a device like this for spin.
Good question. Anyway, Nadal could generate lots of topspin with his old Duralast strung at insanely high tensions. He also was bulkier back in the day....
I think it has more to do with technique and him being Nadal rather than his strings.
Look how crooked some of his main strings are.
Well, better than multi or s-gut. So maybe not fresh anymore, yes. Not snapping back? No.
That's hardly crooked ... maybe you haven't played with multis for so long you forgot what crooked really looks like ?
Strung @25Kilos in that frame, do the same strokes like he does, and you will see the same on your hands.
But that doesn't mean that strings aren't snapping back.
Looks like a practice session, so this is probably what's going on.
Totally unrelated.....I'm surprised Rafa switches wrists with his watch on and off court.
They are still snapping back big time. The strings are barely out of position. Hehe - this is funny - you are pulling are leg right Mikeler? We need a counter photo of a used PSG string bed before the player straightens all 16 mains after they lose a point when the tennis ball passes right through the string bed due to the space created by the string not snapping back. Come on man - hehehe.
They are not perfectly straight, therefore snapback must not be occurring. I bet he can barely get above 3,000 RPM with that particular setup.
Yeah no. Post a pic of a multi after a practice session. Forbidden to straighten the mains after hitting of course. Even if they don't become perfectly straight, the last time I hit with poly, it still was 100 times more straight after a practice session than my Hex Multi ever was after few hits.
Maybe it would kill your arm, but put some co-poly in the low 50's and hit a bit to see what happens.
I think they are snapping back, albeit not completely. And even in the positions shown in the picture, they'll still deflect and snapback, albeit not optimally.
Personally I wonder if his strings in that picture are either dying or dead. But to get back to your OP, he generates his spin primarily from technique.
Dying IMO. The stencil is fading.
I agree. The strings are definitely snapping back. Nadal's shots should pull the strings completely out of position if it's not snapping back. But it's still mostly straight. The slightly crooked strings probably stopped by the friction of the shaped string during the last stage of the snapping back motion.
They are snapping back. RPM Blast was specifically designed to snap back especially well, as Babolat's Lucien Nogues explained to RSI last year:
Q: How much do geometrically shaped strings contribute to additional spin on the ball?
[Lucien]: Geometric strings such at Babolat RPM Blast and Pro Hurricane Tour do help with additional spin on the ball but the reason is different than what most people actually think. The additional spin doesn’t come from the strings gripping the ball more, but rather from an octagonal cross section string that allows the main strings to “slide” with less effort over the cross strings, which increases the spin. The spin comes from the movement of the main strings rather than the texture of the string.
Full interview: http://www.racquetsportsindustry.com/articles/2012/07/19_the_stringers_file_lucien_n.html
What has happened in the photo Mikeler posted is simply that his strings are not snapping back perfectly into line. There could be several reasons for this, but it does not necessarily mean that they are failing to snap back at all, like notched syngut or multis. For example, they could be snapping back with such vigor that they actually overshoot their original position, and then must snapback a second time in the opposite direction, but by this point they may not have enough energy stored in them and stop moving slightly beyond that original position. They definitely snap back for him when his sticks are fresh, and they are still snapping back when that photo was taken, because if they didn't his shots would suddenly start landing long. And we can be assured that Rafa would notice that and switch to a fresh stringjob.
The paint on the strings is a bad idea, BTW, unless they are using very slippery paints nowadays.
Who said anything about strings snapping back causing spin?
Yup, his strings look pretty crooked to me, too:
See Breakpoints pic too.
I wouldn't take a practicing picture and posing picture seriously. I wouldn't mind practicing with a less than optimal stringbed either. I think if you guys just googling Nadal, see how many pictures you see there have crooked strings, how many have straight strings, this topic probably would be dead by now.
Why do you think Nadal change rackets so often during the match? Once the string stop snapping, Nadal start hitting more balls out, time for a new stringbed!
Did you just cite Breakpoint's post to help solidify your point? That's like applying for adoption and putting Casey Anthony as a character reference.
That is Babolat Duralast, which has a different surface than usual polys and does not snap back well even freshly strung. Other polys with the same type of surface are Pacific XForce, MSV Focus Evo, Polyfibre Panthera..
Makes me think if Rafa is still actually using Duralast painted black nowadays from the OP's pic..
They are snapping back. Perhaps not 100% but pretty damn close. In the highspeed footage you can see that some of the mains get pushed so much that they're touching the neighbouring string.
Huh? So Nadal practices hitting with less spin during practice? That doesn't make any sense.
I don't think Nadal plays with any of stringbeds long enough for them to stop snapping back (if they indeed snapped back when new). I mean if he strings every day, that's not long enough for his strings to stop snapping back, especially since he uses so many different racquet per day.
Yet, Nadal has always produced the most monster spin of anyone on tour? Hmmm.........
And wouldn't painting the strings make them snap back even less?
You've only been here for 9 months, son. What do you know?
This makes no sense whatsoever - contact area in case of octagonal strings is greater than in case of normal "round" strings.
Exactly! I forgot to respond to that post with the same comment as yours. The surface areas that comes into contact between two round strings is much smaller than between two flat sides of octagonal strings, thus, the frictional forces between the two octagonal strings should be greater than that between two round strings. Thus, octagonal strings should be less slippery and snap back less than round strings do, all else being equal.
I did not say anything about snapping back vs spin. I was only commenting on the characteristics of Duralast, which does not snap back like RPM Blast etc. A poly that snaps back may give you around 2 per cent increase in rpm over a poly that does not snap back, at most. It is the technique that matters. Give Rafa a full bed multi and he can still produce more spin than many other players.
This is precisely why I am suspicious the black strings in the OP are painted, as they did not snap back. Simple. Unless the string is already dead of course.
To me, it seems like the edged strings give the most spin not the smooth ones.
He doesn't go into detail on exactly how this works. Friction force is the same regardless of surface area. This is one of those surprising things you learn in Physics 101. So it shouldn't make a difference whether the contact surface is small or large - the total friction force should be the same. So actually, his comment makes no sense for the opposite reason. But, what I think he probably means is that it's better to have two flat, hard surfaces sliding against each other than two round, pointed surfaces, which might have a tendency to bite into each other. If you've got two rounded surfaces the pressure might be greatest at the apex of the curve of each string, where the two strings will cut into on another. We know this happens, as main strings get notched and cross strings get dented. With two flat strings, on the other hand, the pressure is more equal over a larger area, which one would think would reduce the tendency for the two strings to cut into each other.
The recent work by the TW Professor on how strings go dead suggests that "deadness" in polys is largely a function of increasing interstring friction as the strings become worn, notched and dented at the intersections over time. So while new, two round strings might slide just as well upon each other as two flat-surfaced strings, but after a hundred pro-level impacts, perhaps the surfaces of the flat-surfaced strings are still flat and smooth while the round strings are becoming dented and notched, inhibiting free string movement.
I think that is probably what Babolat found when testing shaped polys like RPM Blast.
That's my point also. I don't believe that strings snapping back gives the ball any more spin because the ball is well gone from the stringbed by the time the strings snap back. The effect is minimal at best. It's the stiffness of the poly stringbed that gives the ball more spin assuming you have the technique.
As they should due to the shaped strings biting into and grabbing the ball better (more friction). That's their intended design to create more spin. More evidence that it's not the snapping back that causes the spin.
Cofocus Hex crosses are pretty spinny
That depends. The coefficient of friction does remain the same regardless of surface area. But if the force per square inch is also the same, then of course the more surface area you have the greater the total frictional force. That's why performance sports cars use huge brake pads to create more frictional force to stop the car from a high rate of speed rather than use tiny little brake pads.
I actually think it's more to do with heat dissipation. You can have smaller pads but if you stand on your brakes and your ABS kicks on, that's it. Doesn't matter if you had bigger pads, you will stop in the same distance. What the bigger pads will do is kick in the ABS a little sooner on the pedal travel.
What does matter is that if you have smaller rotors it will overheat after a few stops and your car just won't stop anymore. There was a GTS viper that was doing lapping days in Homestead speedway when I was there that cooked his brakes in 2 laps! I took me about 5 laps of hard driving to do, but when the brake pedal sinks to the firewall and your car isn't slowing down that means it's time to pull in and take it easy for a bit and upgrade the brake system as the next mod.
I've seen so much snapback theory lately, this is really the point I was trying to make with this thread. Of course I was having a little fun with Rafa's strings that were barely out of place. Carry on...
It was funny.
This isn't true. Compound X from Michelin gives a COF against concrete of Z. If you put this compound in the form of a bike tire and slap it on the back of a Noble, you're just going to shred the tire within a 10th of a second. Now, if you put some 345s on the back, same compound, you'll go like a stabbed rat. What you're doing is distributing the force that the drivetrain exerts against the ground over a greater area. If you have a greater COF, then this is what gives you more grip over a tire the same size but not as sticky. The force of friction is not higher or lower. The force per unit area acting on a given material is less which allows the material to grip better. This is the reason why dragster tires are not smaller diameter and wider, but rather narrower and extremely tall. The tires don't need to grip laterally, they need to grip in the direction that they're being driven (ignoring the gearing effects of changing wheel diameter). In a road car, that direction is always the same, but depending on how the car is turning, the lateral forces may be higher in which case you distribute that load over a greater area laterally. Friction itself isn't as important.
Mikeler, what exactly was the point you were trying to make?
He isn't, he's trolling the **** out of everyone willing to listen :lol:
What part of "if the force per square inch is the same" did you miss? I kept the force per unit area constant so it can't be less. The same amount of force per unit area over a larger area equals greater total frictional force.
what about the force of gravity? Won't heavier strings be more attracted to the ball?
Not to mention the compounded impact of relativity. Faster swing speed increases relative mass, thereby increasing this gravitational effect. This would explain why lead tape works.
I didn't miss it at all, it just doesn't matter. In your brake analogy, the only way the force per area stays the same when you increase the pad size is if the calipers produce more force. That entirely negates the argument.
I think what you mean is the force remains constant but over a larger area. The force/unit area when the area is larger means that it's actually lower.
I seem to get the most spin from shaped strings. Maybe it is because they have less surface area and can slide back. I get amused with people claiming you need smooth round strings to get SnapBack and spin.
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