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View Full Version : Crosses breaking with NRG2


coach
06-29-2004, 09:36 AM
I use a Pro Kennex 5g with a 16 x 20 open pattern, strung at 62 lbs (65 is max recommended). I have never broken a main, only crosses. This is using a soft string, Tecnifibre NRG2 (17g). Breakage isn't premature but I keep reading that mains are supposed to break first, not crosses. Is this normal with a soft string or does it reflect something else? It's a one piece string job, does anyone recommend going 2 piece with a hybrid? Thanks.

thatballwas_IN
06-29-2004, 11:18 AM
Are you constantly having to adjust the strings?
I play with Technifibre NRG2 18g, and the crosses move way too much and I always have to adjust them. They haven't broken, but I have a dense string pattern.
I think you might want to try a hybrid if you have the same problem. I am moving to a hybrid or all poly string ...

coach
06-29-2004, 11:20 AM
I have to adjust the mains more, but still not too much as I use stringsavers which keep them in place a bit.

NoBadMojo
06-29-2004, 12:26 PM
coach that can happen with that string for some reason. i would usually break the mains w. nrg but the crosses were badly worn when the mains broke and i did break crosses a couple of times w. this string. the main thing is to break them near the center right? :) you may wish to give the new technifibre bi-phase x-one a try..they seem to have alleviated much of this problem as the strings lock much better, there is less tension loss, more durability, and the string seems to play more consistently from sesion to session..it maybe has a touch less power but all of the feel and spin. it's a great string IMO..the next best thing to gut. ed

Match-Point
06-29-2004, 12:32 PM
NoBadMojo is on to somethin'. X-One Biphase is an awesome multi string. Try it in 16 gauge and you will not go back to NRG2. IMHO of course. . . M-P

Eug
06-29-2004, 01:45 PM
Generally, soft multifilaments strings will break in the crosses. This is perfectly ok. When I used to string with Wilson Sensation NXT, I always broke the cross strings. Dont sweat it at all.

tguru
06-30-2004, 03:24 AM
Crosses break due to ball abrasion. String savers can do nothing to reduce this. Multis, due to their construction, will break much sooner than a center core string where crosses are concerned. Switch to a center core string if you want to eliminate the problem.

coachrick
06-30-2004, 07:18 AM
Different Coach here...Anybody compared the NRG with TRC in the same gauge? I've got a number of NRG clients who might trade off some feel and power to pick up a bit more durability. I haven't used enough TRC to get feedback on its longevity. Seems like it might be a good trade-off.

Steve Huff
06-30-2004, 02:54 PM
Multifiliment strings usually do break in the crosses. They fray and break. What I would do is use a hybrid. Use the NRG2 in the mains and something like Gosen OG Micro 17 in the crosses. Since these synthetics are not as elastic as the NRG2, I string them 3-5# lower than the mains. You probably won't be able to tell the difference in play.

NoBadMojo
06-30-2004, 03:38 PM
i dont think multi's usually break at the crosses at all. i dont think any string normally does. i think they CAN break there, and if one does break chances are a main would have broken in the next very short while anyway. unless you have some sort of hybrid. i would 9 times out of 10 break a main or two or 3 w. the nrg and cant remember ever breaking a cross in any other multi i have used other than nrg2. but much of this depends on tension, the frame, style of play, etc. as long as you are making consistently good contact, i wouldnt worry about it. but still..most of the hit comes from the mains. it would be interesting to see how a gosen og hybrid would work though. my .02 Ed

Steve Huff
07-01-2004, 08:07 AM
I used NRG2 and 515 for several years. I don't think I ever broke the mains. The crosses always frayed and broke before the mains did. Also, of the guys I string for, one uses Prince Perfection. His always frays and breaks the crosses first. I'm talking about wearing out. Some guys that hit with a lot of spin and hit really hard my BREAK the mains first, but when the strings just wear out, start to fray etc. it's almost always the crosses in a multifiliment stringjob.

Salad
06-01-2005, 10:33 PM
I have the same experience that the cross breaks first when NRG2 17 is used.

It is an interesting phenomenon. I try to give an explanation as follows:

Conventionally, main breaks because the mono-gut is sawed by the cross. In case of multifilament, the cross breaks because it is planed by the main. How comes?

Take a mono-gut of nylon for comparison, it is the most basic material of synthetic guts,. When hitting topspin or underspin, the mains move laterally (along the stringbed) against the crosses too. Look into a crossing, a crossing point of a main is brushing against a crossing segment of a cross. Though the segment, the displacement of the main is short, thatís enough to set up a one-to-many fight. This process undergoes and a notch on the main forms and in turn, a notch becomes a weak link of the string. Finally, the string breaks at the weakest link. This sawing process is witnessed by examining the saw-cuts, i.e. the notches on the mains.

Now considering a multifilament string made of many fibers of nylon. One of the advantages of multifilament is that when a fiber breaks, the breaking point is NOT a weak link of the string, the remaining fibers just share the tension of the broken fiber. As more fibers break, the string gets thinner, alike a higher gauge string is used, that implies the string is still playable.

To increase of lifetime of multifilament, fibers are protected by a coating and/or a wrap. The coating is an abrasion resistant material.

At home, you find many electrical cables which are divided into two groups, namely, single-wire and multiple-wire. Single-wire cable is rigid and used in electrical wiring, permanent installation. Multiple-wire cable is more flexible and widely used in electric appliances.

Same as multiple-wire cable, multifilament is more flexible, i.e. bends more if same force applies. It is equal to say that the flexural modulus is lower. When the mains move, humps (bends) of the crosses at crossings formed by the weaving of mains and crosses, move. A bending stress shifts along the crosses. Note that the moving mains are just undergoing an abrasion process. As the mains move cyclically, the repeated bending stresses on the crosses make the coating fatigue and break eventually. Once the protection is gone, the fibers of nylon of cross expose to the abrasion resistant coating of the main. The fibers of the cross are planed off bit by bit by the mainís coating. Finally, the fibers left are overloaded by the excessive tension and the cross string breaks.

Occasionally, the protection of main gone first, then the sawing process on the main takes over and the main breaks first. The occasions like tension, style of play and etc. Take tension as an example, low tension makes the bending stress less, in turns lessening the planing effect. I string my Dunlop 200G with NRG2 17 at 65lb, cross breaks first usually.

Any opinions?

leog
06-01-2005, 11:05 PM
tguru is right on, about the friction from the ball. I'm currently hybriding Bab PH18 with NRG2 18 in the crosses, and (no duh...) the NRG2 breaks while the BPH shows no wear at all. This is the first time my crosses have EVER broken first, but considering it's a hybrid with poly mains, I'm not surprised.

The NRG2 does move a lot, and it definitely shows wear from the ball, eventually so much wear that it snaps...Next I'm going to hybrid X1BP 18 with PSG 18 in the crosses--should be a totally different feel, and, considering how fast my NRG2 is breaking right now, possibly the same durability.

TwistServe
06-01-2005, 11:08 PM
NRG218 < X1BP18 < Timo18

Salad
06-02-2005, 12:19 AM
Hi Leog,

Examining the multifilament string, I can easily locate my hitting spot on the stringbed because there is fuzz. The fuzz is formed by the broken fibers of the string. To look closer, I find most of the fuzz around the crossings is on the side that the strings in contact, not the side hitting the ball.

Bent
06-02-2005, 01:06 AM
I always break the X's (E-matrix 16g) in my Dunlop mw 95 (18x20). With string savers.

Salad
06-02-2005, 01:26 AM
Hi Bent,

Thank you for message. String savers make the humps higher, that means the strings bend more at the crossings, in turn makes the fatigue come earlier. In addition, adding savers increase the tension.

The savers reduce the effect of abrasion but breaks the PROTECTION earlier. BTW, the thicker string, i.e. lower gauge no., makes the humps higher too. That' may be the reason why you always break the cross