Low Friction Poly X's For Gut Mains : Softer Alternative to MSV Co-Focus?

corners

Legend
Hey Corners, quick question, as I haven't had time to read the whole ZX thread... for someone using Gut/Poly at 52/49lbs, and looking to try Gut/ZX, should I come in at the same cross tension? I know people are saying it takes time to find the right tension for the ZX, but I'm thinking just compare apples to apples with the same tension, and 49 crosses should be ok... or maybe too low?

Well, with the caveat that I might no know anything at all, below is a post from the Zyex Monogut thread I wrote this morning in response to JackLondon001. The whole thing explains my thinking for why gut/ZX probably needs to be strung quite a bit tighter than gut/poly, but I don't get to gut/ZX until the end. But I understand your thinking of just using your normal gut/poly tension to establish a baseline for comparison purposes. The only thing that would give me pause are the few reports of gut/ZX "moving all over the place," when strung low.

I think 18g Kevlar/ZX would have a much better performance, if it snaps back like Trav said it did in his 18x20.

From my readings of the TW Professor's papers on string snap back and string patterns, I would think that if kevlar/ZX snaps back in an 18x20 but does not in a more open pattern, that the fix would be to up the tension in the open pattern. In this paper on how string stiffness influences snapback, the Professor found that when kevlar mains were used in a very open (16x10) pattern, that the cross strings had to be tensioned quite tight. If they were too loose, the kevlar mains slid too far out of line and then failed to snap back in time to impart additional spin.

Those experiments with kevlar mains and copoly crosses in extremely open patterns, as well as others in that paper done with conventional patterns, led him to suggest "goldilocks principles" of snapback-generated spin:

The optimization rules for spin appear to be "Goldilocks Principles": the stringbed must be not too soft and not too stiff, not too closed and not too open, and not too rough and not too smooth. You can have too much or too little of each. Stiffness helps keep movement in check in open patterns and helps to overcome friction in tighter, higher friction environments. But stiffer materials and higher tensions also create greater inter-string friction and may too severely constrain lateral string movement, thus not getting the maximum spin benefit.

So if the cross strings are too tight, or there are too many of them, the main strings may not be free enough to slide and stretch sideways with the ball. So no additional spin from snapback because the strings weren't able to slide sideways.

But if the crosses are too loose, or if there are too few of them, the main strings will be able to slide sideways too easily and too far, and then not have time/energy to snap back in time, or with enough energy, to impart additional spin.

I have a friend who is going to try Gut/ZX in a Fischer vac pro 90, which is a very low powered racket. I will be stringing it for him and probably will hit a few balls with it. I had pacific tough gut in that racket at 51 lb and even that was low powered as full setup.

I have high hopes for gut/ZX, but after reading several reports about it, as well as about other ZX hybrids, I suspect that the ZX crosses, being so flexible, are going to demand higher tensions than people used to gut/poly would think. I usually do gut/soft copoly at around 50 in a 16x19 midsize. I'm thinking between 57 and 60 with gut/ZX might be about right to get the ZX crosses stiff enough to prevent too much sideways gut movement in that open pattern. The posters who have reported on gut/ZX have pretty much all strung low, around 50 if I remember right, and have described the strings "moving all over the place." This suggests to me that, at those low tensions, the flexible ZX is allowing the flexible gut to slide way too far sideways, where it either gets stuck, or alternately, does snap back, but after the ball has left the strings. Without the resistance of the ball, the sideways snapping strings might then snap back past their original position and get stuck on the "other" side of the stringbed.

So gut/ZX might be the ultimate "goldilocks" setup, because both strings are so flexible, requiring lots of trial and error to get the tension "just right." If so, it could be very expensive to find "just right"; and worse, "just right" might slip away as soon as the ZX loses some tension. Hopefully not.​
 

corners

Legend
Just to add to the above, I compared ZX 16 to a soft copoly that I've used many times with gut mains, Proline II 1.25. I looked at the deflection numbers at TW University, and it appears that ZX strung at 60 pounds deflects the same distance as Proline II strung at 50 pounds. And, at 60 pounds ZX exerts a peak force approximately equal to Proline II strung at 30 pounds (so it should be more comfortable even at that high tension). In addition, the energy return of ZX at 60 is 91.6% versus 84.5% for Proline II at 50.

So, if we put stock in the numbers, ZX as a cross with gut mains at 60 should perform similarly to Proline II as a cross at 50, except that comfort and "pop" should be significantly improved.

But one final thing to consider is how gut mains at 60 behave versus gut mains at 50. The tighter gut mains will obviously deflect a shorter distance, but probably with more energy, than looser ones would.

Here's a collection of the deflection numbers for ZX 16, Proline II 1.25 and Toughgut 16 at three reference tensions (these are post-tension-loss data):

62 Pounds

Toughgut 30.8 mm
Proline II 30.0 mm
ZX 16 32.1 mm

51 Pounds

Toughgut 33.0 mm
Proline II 32.0 mm
ZX 16 35.2 mm

40 Pounds

Toughgut 16 36.0 mm
Proline II 35.1 mm
ZX 16 40.0 mm


So, if I used gut/PL II at 51/51 my gut mains would deflect 33.0 mm and my PLII crosses would deflect 32.0 mm.

If I switched to gut/ZX 16 at 62 pounds, my gut mains would deflect 30.8 mm and my crosses would deflect 32.1 mm.

Extrapolating from these data, with gut/ZX strung at 55, the gut mains might deflect 31.4 mm and the ZX crosses 33.7 mm.

I'm not sure how useful these numbers are, but they are something. The wildcard is the different interstring friction characteristics of the ZX versus Proline II. TWU's testing showed Proline II 1.25 to have an interstring coefficient of friction of 0.101, while ZX 16 tested at 0.088. According to these numbers, ZX is actually more slippery than Proline II, but playtest reports suggest that this slickness might not last as long as it does with copolys. This might be due to a coating that gets rubbed off, or degradation of ZX's relatively softer surface.

Just looking at all this, I'm thinking 57/57 might be interesting to try for myself.

Pity that TWU hasn't tested Mosquito Bite.
 

Torres

Banned
for someone using Gut/Poly at 52/49lbs, and looking to try Gut/ZX, should I come in at the same cross tension?

I think that will be far too low a tension if you're using ZX. You can get away with it with poly because it has an inherent stiffness to begin with, but ZX is a different animal altogether.

Torres...I don't think he's much into gut/poly, so he might not be of much help either.

I love gut/poly, particularly Wilson Gut 16 / Alu Rough 17. But its only as good as the poly lasts, which in the case of Alu is only a couple of hitting sessions before the poly loses its crispness and tension, and the gut becomes overpowered.

It lasted slightly longer in my 6.1 95/18x20 due to the stick's greater inherent control but its still far too expensive a setup to run as a amateur player's setup because as soon as the control goes and the poly becomes dead or loses too much tension, I want to cut the strings out. It's an amazing string combination in that 6.1 though when fresh.

Have also tried VS/CoF which was good for a couple of hours or so but after that you have similar problems as with Alu. I've yet to find any poly that holds tension well enough to keep the gut from trampolining and is slippery enough to use on a regular cost effective basis. Discho gut / 4G was surprisingly crude, as was Discho Gut / Iontec Salmon Hex 1.20. Wilson Gut 16 / Weiss Scorpion 17 was crap.

I find it alot cheaper and more consistent in performance terms to restring with full poly every week.

I don't mind trying VS/ZX. I actually have some lying around somewhere. Originally, I wasn't convinced that ZX would be slippery enough or stiff enough to hold the gut together but having tried ZX at higher tensions, it's possible it may work as its characteristics seem very tension dependent. Not sure what tensions might be needed but it would have to be fairly high as gut/ZX would be pretty powerful if the tension is too low. I would guess it would need to be in the high 50s or maybe 60lbs CP.

I have high hopes for gut/ZX, but after reading several reports about it, as well as about other ZX hybrids, I suspect that the ZX crosses, being so flexible, are going to demand higher tensions than people used to gut/poly would think. I usually do gut/soft copoly at around 50 in a 16x19 midsize. I'm thinking between 57 and 60 with gut/ZX might be about right to get the ZX crosses stiff enough to prevent too much sideways gut movement in that open pattern.

The posters who have reported on gut/ZX have pretty much all strung low, around 50 if I remember right, and have described the strings "moving all over the place." This suggests to me that, at those low tensions, the flexible ZX is allowing the flexible gut to slide way too far sideways, where it either gets stuck, or alternately, does snap back, but after the ball has left the strings. Without the resistance of the ball, the sideways snapping strings might then snap back past their original position and get stuck on the "other" side of the stringbed.

So gut/ZX might be the ultimate "goldilocks" setup, because both strings are so flexible, requiring lots of trial and error to get the tension "just right." If so, it could be very expensive to find "just right"; and worse, "just right" might slip away as soon as the ZX loses some tension. Hopefully not.

I share your sentiments and also agree that those other guy(s) strung gut/ZX at far, far too low a tension.
 
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Torres

Banned
Actually looking around, I've actually a few sets of gut knocking around:

1. Wilson 16
2. VS black 16
3. Klip Legend uncoated 17
4. Discho Gut 16 (nasty stuff and pretty crude with a high friction wax coating) http://i1122.photobucket.com/albums/l528/TorresNo9/CameraZOOM-20120725220449484.jpg

Also when I played with full bed ZX 1.27 in a BLX JP (96/16x20) @ 56lbs CP, it didn't feel overpowered.

Wilson 16 / Alu Rough 17 in the same stick at 54/50lbs CP and the gut felt overpowered. Was fine in a 6.1 95/18x20 though.

I'm thinking maybe trying Wilson or VS at 60lbs with a 5% or 10% prestretch, and then maybe ZX 1.27 crosses at 58lbs. Or maybe 58/56 CP.
 
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mikeler

Moderator
Actually looking around, I've actually a few sets of gut knocking around:

1. Wilson 16
2. VS black 16
3. Klip Legend uncoated 17
4. Discho Gut 16 (nasty stuff and pretty crude)

Also when I played with full bed ZX 1.27 in a BLX JP (96/16x20) @ 56lbs CP, it didn't feel overpowered.

Wilson 16 / Alu Rough 17 in the same stick at 54/50lbs CP and the gut felt overpowered. Was fine in a 6.1 95/18x20 though.

I'm thinking maybe trying Wilson or VS at 60lbs with a 5% or 10% prestretch, and then maybe ZX 1.27 crosses at 58lbs. Or maybe 58/56 CP.

I vote for Wilson gut 16 mains or B5E mains.
 

Torres

Banned
I vote for Wilson gut 16 mains or B5E mains.

Having tried a few different poly mains (Black Magic, Yonex PTS etc) with ZX crosses, I'm pretty confident B5E/ZX will work, so I'll do that after the gut/ZX test. The characteristics of B5E (stiff, dead feeling, bitey, low powered, consistent etc) is likely to mesh well with the ZX (soft, powerful, good feel, changeable consistency etc).
 

mikeler

Moderator
Having tried a few different poly mains (Black Magic, Yonex PTS etc) with ZX crosses, I'm pretty confident B5E/ZX will work, so I'll do that after the gut/ZX test. The characteristics of B5E (stiff, dead feeling, bitey, low powered, consistent etc) is likely to mesh well with the ZX (soft, powerful, good feel, changeable consistency etc).

I think you'll find B5E much less stiff as just a main string. I'm not saying it is the softest one out there by any stretch, but for some reason as a main string it does not bother my arm at least in the warmer weather.
 

Ramon

Legend
I think you'll find B5E much less stiff as just a main string. I'm not saying it is the softest one out there by any stretch, but for some reason as a main string it does not bother my arm at least in the warmer weather.

How long can you play with a B5E hybrid before your arm senses that it's dying?
 

ChicagoJack

Hall of Fame
I'm copying and pasting my demo list, digits, and opening comments, just to the give the next few final write ups a proper context. I've found something that suits my needs and thought I'd report back, since some of you have expressed interest in what I finally ended up with after many months of experimentation.

I've been on a hunt for a low friction, and most of all, comfortable option for a cross string with gut mains. I've been playing with Gut/Poly for about five-six years now, and Gut/Co-Focus for a majority of those years. But I've been searching for something a little more comfortable. I've cross referenced the string friction rankings [1] with string stiffness, as well as tension loss. Below is a list of demo possibilities that popped up based on those criteria. My approach is to use the available testing data only to trim the demo pool from the 900 or so commercially available string, down to a more manageable 20-30 to demo. Then I forget about the data entirely once I'm on the court, and I use what works best and feels right.

March 17, 2014 Edit : Underlined means I've demoed it. Grey Font just means it's not a poly string. One of the things I discovered while fishing around for low friction string, is that there were (surprisingly) quite a few non-poly strings with friction digits in the poly neighborhood, with lower stiffness and better tension maintenance. So I gave them a special pass into my short list of demo options.

( stiffness lbs/in ) ( actual pre-test tension, reference tension was 62 lbs, fast swing ) ( inter-string friction )

( 086.3 ) ( 54.4 ) ( 0.103 ) .. Pacific Prime 16
( 089.2 ) ( 53.8 ) ( 0.180 ) .. Pacific Classic 16
( 092.6 ) ( 54.2 ) ( 0.173 ) .. Wilson Natural 17
( 097.7 ) ( 53.1 ) ( 0.147 ) .. Babolat VS Team 17
( 099.4 ) ( 51.9 ) ( 0.245 ) .. Wilson Natural 16
( 104.6 ) ( 54.3 ) ( 0.298 ) .. Klip Legend Uncoated 16
( 101.7 ) ( 51.1 ) ( 0.124 ) .. VS Natural ThermoGut 16 Touch
( 105.2 ) ( 54.2 ) ( 0.194 ) .. Klip Armour Pro 16

( 118.3 ) ( 39.0 ) ( 0.088 ) .. Ashaway MonoGut ZX 16 Nylon/Zyex
( 161.2 ) ( 48.1 ) ( 0.085 ) .. Volk Gripper 17 Nylon
( 166.3 ) ( 27.5 ) ( 0.098 ) .. Topspin Cyber Flash 17L
( 171.5 ) ( 47.6 ) ( 0.079 ) .. Gosen Compositemaster II 16 Nylon
( 176.0 ) ( 50.4 ) ( 0.089 ) .. Head FXP Power 17 Nylon
( 178.9 ) ( 49.3 ) ( 0.080 ) .. Gosen Powermaster II 16 Nylon
( 180.6 ) ( 37.8 ) ( 0.090 ) .. Gosen Sidewinder 17
( 181.2 ) ( 49.1 ) ( 0.082 ) .. Volkl Synthetic Gut 17 Nylon
( 181.2 ) ( 48.8 ) ( 0.088 ) .. Gosen Nanosilver 17 Nylon
( 181.7 ) ( 30.0 ) ( 0.102 ) .. WC Silverstring 120
( 182.9 ) ( 48.5 ) ( 0.075 ) .. Gosen Powermaster I 16 Nylon
( 183.5 ) ( 49.7 ) ( 0.089 ) .. Gosen AK Pro 17 Nylon
( 188.0 ) ( 47.8 ) ( 0.081 ) .. Klip Synth Gut 16 Nylon
( 188.0 ) ( 30.9 ) ( x.xxx ) .. Yonex Poly Tour Pro 1.25
( 000.0 ) ( 00.0 ) ( 0.000 ) .. Weiss CANNON Mosquito Bite 18 (Not In TWU Data Base)
( 189.2 ) ( 44.7 ) ( 0.114 ) .. Technifibre Pro Mix 17Nylon/Poly
( 191.5 ) ( 34.3 ) ( 0.083 ) .. Big Hitter Black 7 17, edged
( 192.0 ) ( 34.2 ) ( 0.083 ) .. Big Hitter Silver 17
( 192.6 ) ( 32.9 ) ( 0.112 ) .. Polyfibre Poly Hitec 18
( 192.6 ) ( 30.2 ) ( 0.070 ) .. IsoSpeed Pulse 16
( 193.2 ) ( 33.3 ) ( 0.071 ) .. Gosen Polyon Polybreak 18
( 193.7 ) ( 33.1 ) ( 0.092 ) .. Head Sonic Pro 16
( 197.2 ) ( 38.3 ) ( 0.120 ) .. Babolat Pro Hurricane 18
( 199.5 ) ( 34.3 ) ( 0.090 ) .. Topspin Cyber Blue 17
( 200.0 ) ( 00.0 ) ( 0.089 ) .. MSV Co-Focus 17L .. (Stiffness estimated by corners, USRSA Digits n/a]
( 200.0 ) ( 30.9 ) ( 0.100 ) .. Polyfibre TCS 17
( 200.6 ) ( 35.3 ) ( 0.097 ) .. Kirschbaum Pro Line II 18
( 203.5 ) ( 33.4 ) ( 0.087 ) .. Head Sonic Pro 17
( 205.0 ) ( xx.x ) ( 0.072 ) .. Solinco Revolution 18 .. [corners estimated data]
( 205.5 ) ( 35.7 ) ( 0.075 ) .. Solinco Tour Bite 17, edged
( 206.3 ) ( 35.6 ) ( 0.085 ) .. Gamma Zo Twist 16
( 206.9 ) ( 34.9 ) ( 0.074 ) .. Gosen PolyMaster II 16, flat
( 210.9 ) ( 35.4 ) ( 0.082 ) .. Volkl Cyclone 18
( 210.3 ) ( 30.0 ) ( 0.085 ) .. Polyfibre Hitec Premium 16
( 211.5 ) ( 35.1 ) ( 0.083 ) .. Gosen Polyon SP 17
( 211.5 ) ( 36.5 ) ( 0.092 ) .. WC Scorpion 1.22
( 213.2 ) ( 36.3 ) ( 0.089 ) .. MSV Co-Focus 16L
( 214.3 ) ( 35.6 ) ( 0.074 ) .. Solinco Outlast 17
( 214.3 ) ( 35.9 ) ( 0.085 ) .. MSV Hepta Twist 17 edged
( 222.3 ) ( 38.7 ) ( x.xxx ) .. Signum Pro Poly Plasma 17L , 1.18
( 225.0 ) ( 39.6 ) ( x.xxx ) .. Tecnifibre Black Code 18
( 228.0 ) ( 45.7 ) ( 0.069 ) .. Head Hawk
( 228.6 ) ( 39.6 ) ( x.xxx ) .. Prince Beast XP 16
( 323.6 ) ( 36.8 ) ( x.xxx ) .. Signum Pro Hyperion 17
( 237.0 ) ( 37.3 ) ( 0.098 ) .. MSV Focus Evo 17
( 262.3 ) ( 45.6 ) ( 0.071 ) .. Ltec Premium 4S 16L
( 273.2 ) ( 51.3 ) ( x.xxx ) .. Luxilon 4G 16L, 1.25

Links: [1] String Friction Rankings , String Movement , Inter-string Friction , String To Ball Friction , Rank Strings By Spin Potential , USRSA String Selector Map 2012 , Gosen Sidewinder Video Review , Big Hitter Black 7 Video Review , Volkl Cyclone Video & Written Review
- Jack
 
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ChicagoJack

Hall of Fame
I've tried a few more string set ups since the last few conversations here in July of 2013, and then the thread floated to the bottom of the board. A few months ago, I strung up all 9 of my identical Pro Ones on the same day, with all of the strings I've had a burning desire to demo, just to settle my mind once and for all. One of the things about string demos is that I get very wacky and uncertain when I'm comparing a current string to the memory of another string. Doing a one and done test like this is one of the main reasons an amateur hack player like myself wanted 9 racquets. I don't like feeling uncertain about my choices.

Here's what I strung up:

My Three Favorites, (2012-2013) I Thought Of These As The Ones To Beat
1. 60/52 … Mains: Wilson Natural Gut 16 | X's: Yonex Poly Pro Tour Black (16L / 1.25mm)
2. 60/52 … Mains: Wilson Natural Gut 16 | X's: Wiess CANNON Mosquito Bite (18g / 1.16mm) Red
3. 54/54 … Dunlop Black Widow (18g / 1.21) (Rainy Day Back Up)

Always Wondered About:
4. 60/52 … Mains: Wilson Natural Gut 16 | X's: Gosen SideWinder (17g /1.22-1.24)
5. 60/52 … Mains: Wilson Natural Gut 16 | X's: Gosen PolyMaster I (16g / 1.02-1.46)
6. 60/56 … Mains: Wilson Natural Gut 16 | X's: Ashaway MonoGut Zx Red (16g / 1.27mm)

Rainy Day Back Ups Options (No Gut)
7. 60/60 … Full Bed : Ashaway MonoGut Zx Red (16g / 1.27mm)
8. 60/60 … Full Bed : Volkl Synthetic Gut
9. 60/60 … Full Bed : Volkl Gripper 60

Demo Comments:

1. 60/52 … Mains: Wilson Natural Gut 16 | X's: Yonex Poly Pro Tour Black (16L / 1.25mm) This was my go to set up for most of the 2013 season. The major appeal for me is that it's spinny, (like most gut/poly) but a bit more comfortable than Co-focus. The change to a larger 16L cross, seems not too big a deal.

2. 60/52 … Mains: Wilson Natural Gut 16 | X's: Wiess CANNON Mosquito Bite (18g / 1.16mm) Red
Mosquito bite is really awesome, really nice impact feel, hits like buttah. Came highly recommended by very credible TT members and did not disappoint. I had a hard time choosing between it and the Yonex PTP. My feeling is that Yonex is slightly more consistent in response, but that I get a slightly spinnier ball with the mosquito bite.

3. 54/54 … Dunlop Black Widow (18g / 1.21) (Rainy Day Back Up)
I discovered this string quite by accident. It was strung on the very first Pro One that I acquired used. It's a good fit for the P1 from the baseline, but not so great at net. I'm a doubles specialist, and all court singles player so it's ultimately not a great solution, but I always carried it in my bag for rainy days, or days it seems like I can beat my guy by hanging back three feet behind the baseline and try to hit run around FH's all day. It gives me a similar ball and trajectory to the other textured polys that I like, Tour Bite, BHBR, and BHB7 but feels a whole lot more comfortable to me.

4. 60/52 … Mains: Wilson Natural Gut 16 | X's: Gosen SideWinder (17g /1.22-1.24)
Big surprise here. I didn't expect to switch set ups a few days before Nationals, but I liked this cross so much I played with this one racquet the whole 4 days of the tourney, and for several weeks after. It's the most comfortable Gut/Poly I've ever tried, and the response is very consistent. I got dialed in with this string withing just a few hours. However.. I don't think the unique profile does anything at all. In actuality, it's nothing like the extreme shape you see on the packaging. I mean yes, you can feel a little twisty edge there, if you brush a finger on it, but it seems pretty round none the less. The shape of BHBR, Tour Bite, or any number of other edgy strings feel much more distinguished to the touch. What attracted me to try this string is the data points for stiffness, tension loss, and friction ALL stood out favorably, almost appearing as anomalies in all three categories. I would say this is one of those times where the Lab does match up with the court.

March 18 Update:

5. 60/52 … Mains: Wilson Natural Gut 16 | X's: Gosen PolyMaster I (16g / 1.02-1.46)
Uhg. This was the one string (as a cross for gut mains) that I was most intensely curious about, and had the highest hopes for. The idea is that the flat profile allows for less weave angle, which would allow the mains to move much more freely. Unfortunately I didn't give this string a fair shot on a level playing field. When my stringer handed me back my stack of frames he said that he couldn't get a good grip on the string from the tension head. It kept slipping during the tension pull. Consequently, the crosses are way under tension, and the whole stringbed feels loosey goosey and unplayable. The rebound angle was something I noticed within the first few hits, clownishly high over the net, landing short in the court. Dont know if this a tension thing or a profile thing, but both are probably conspiring equally to produce this unique flight path. I still have another half set to try again. I also have un-opened full sets of Gosen Compostite Master II, and Poly Master II, but I'm not sure if I'll ever string them. Seems like most of these really unique sets from Gosen are out of production, (or going out of production) and getting pretty hard to find. Coupled with the stringing difficulties, and the fact that I'm really digging the Gut/zx, I've got these options on the back burner.
 
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ChicagoJack

Hall of Fame
March 18, 2014 Update:

6. 60/56 … Mains: Wilson Natural Gut 16 | X's: Ashaway MonoGut Zx Red (16g / 1.27mm)

Lower Trajectory Didn't Work At First, Love it Now: Not love at first sight. but the one I'm currently happily married to. Took me quite a while to understand this string, and took me a little while to get my stroke grooved to it, but I'm so happy with it, I've ended my search and demos. My first experience with this combo was really confusing. It sounds crisp and crunchy on impact, but feels really comfortable. The uniquely low stiffness implies that Gut/MonoGutZX implies it should be the most powerful Gut/poly combo of all the demos. But out on the court, that's not the impression I get at all. The ball flies much lower over the net, (which has the ball landing shorter in the court) and this gives the impression that it's very a low powered set up.This first (and really confusing) demo was just a week or so before heading into 2013 Nationals at Indian Wells, so the timing was not at all right for confusion, nor a big change. I noticed right away, that playing with this combo would require a racquet face adjustment to keep the balls deep, and from clipping the top of the net.

2nd Round Of Testing : I played with that one hero frame strung with Gut/Sidewinder for the whole week before, the four days of the tournament, and then for several weeks after. That my friends, is one really awesome gut/poly combo. Long story short ... For 5 weeks starting January, didn't touch a tennis ball, I was a caretaker for an ailing family member, then got severe Bronchitis. When I finally returned home and got back on the court, I was completely out of my groove. So this aspect of the Gut/Zx which I didn't like at all months before (low trajectory) wasn't on the table. I re-booted the whole demo process with the nine racquets all over again, without an innate sense of where the ball should be going, given my racquet angle and stroke. Being so out of my usual zone allowed me to see this combo in a whole new way. I'm sensing increased comfort, increased control, all with spin potential that equals any other setup I've tried. Oh, and this stuff beats the pants offa Poly in terms of tension maintenance that's for sure.

I'm Done With Poly : When this stuff first came out it created quite buzz here a TT , and I read most of the dialogue from the sidelines with interest. At the time, most peeps were demoing it as a full bed, or as the mains in a hybrid. Not setups I was particularly curious about. My notion is you put the slippery string in the cross, knowing that gut interacts with slippery stuff pretty well. (Gut/poly creates much less inter-string friction that Poly/Gut) This way you get both max comfort and max spin potential. The few folks that tried Zx as a cross with a gut main did not have great things to say. I can sort of understand that bad first impression, as my first impression wasn't so hot. But I'm glad I stuck with it. I have no need for poly whatsoever. Done with you! I'm throwing your clothes out into the street, and I'm keeping the Van Morrison albums.

Bottom Line: I've regarded poly string as a necessary evil. Gut mains are the hero of my show, but I've needed those slippery poly crosses to get the spin, and this spin comes the cost of a stiff feel, and crazy tension loss. Now I get to have slippery crosses that are comfortable and are much better at retaining tension. Why wouldn't I drop poly like a hot potato? It's no-brainer for me.


March 19, 2014 Update :

7. 60/60 … Full Bed : Ashaway MonoGut Zx Red (16g / 1.27mm)

Rainy Day BackUp For Now, Spin, Tradeoffs : This has become my new back up plan for rainy days, so I'll always carry one stick in my bag string with a full bed. I can also foresee a possibility that I might eventually transition away from Gut/Zx, and just go with a full bed as my primary set up too. One thing I noticed right away in my last two matches, is that when I switched to my full bed, it added noticeable height to my kick serves. That's a huge part of my game, so it's something that has really caught my eye. On ground strokes however, I don't sense the same increase in spin as I do on my kick serves with the full bed. Funny, but that was also the case with my last rainy day option too, Black Widow 18. The game improvement for me regarding BW 18 vs Full bed of Zx would be volleys. Touch and feel is SO much better at net. The trade off here (BW 18 vs. Zx) is pretty favorable. Even money on serves, even money on groundies, much better at net, much more comfortable, and much better tension maintenance.

Impact Feel, Comfort : It's my perception, that the lab generated stiffness ratings are somewhat deceiving. Perhaps deceiving is not the right word... because the numbers are what they are. In my case, I was looking at the digits and seeing that gut lives in the 86-105 lb/in neighborhood, with Zx one street over and three houses away at 118. The softest poly's living a few miles away in the 170's. So perhaps I had expected near gut-like comfort before even hitting a single ball, and this clouded my perception. Perhaps my starting tension (60lbs) has something to do with this, but I would have guessed stiffness digits something similar to a stiff multifiber had I not known better. Head Rip Control sort of came to mind at one point, in that the impact feel is pretty damp, but sort of dead, like poly and it sort of looks like a poly flight path as you study the ball after hitting. What's unique here is that my experience correlating impact feel and arm safety does not seem to apply at all. While I expected a much more comfortable impact feel, my arm certainly digs it. I'm mostly recovered from the first ever case of TE I acquired 2 summers ago after a brief romance with a 2012 PD. Playing 3-4 days in a row can sometimes bring faint tinges of that once pretty severe injury. Since dumping Gut/Poly for Gut/zx, it seems that my TE might clear out altogether once and for all.

Notching : Corners has asked about notching, and that's one thing that has stood out for me. It seems pretty notch resistant, at least compared to the full poly poly I have ( Dunlop Black Widow 18 ) that was strung on the same day. It's difficult to keep track time I have on each of my 9 test frames, but for sure have more time on my full Zx set up than I do than full poly. The Black Widow is showing U shaped notches, and the Zx is showing just the faintest dent, really more like faint creases where you can see where the string would sit, with no abrasion at all. On the Gut/Zx string bed, the Zx is pretty smooth, even smoother than the full bed. You can see the faintest crease mark where the string would sit, but that's about it.
 
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moonballs

Hall of Fame
( 118.3 ) ( 39.0 ) ( 0.088 ) .. Ashaway MonoGut ZX 16 Nylon/Zyex

Chicagojack, regarding the above set up, what is your finding? I see it underlined but greyed out so not sure if you have tried.

I am using ZX main Gosen SG cross 54/53. Last night I played one hour on indoor clay and I lost to someone I shouldn't have. This was the fourth hour of the setup. In the first three hours it played great. But yesterday the ball started to fly long a lot. I am puzzling whether it was because I haven't played on clay the whole winter or the string bed is starting to loosen up too much.
 

colowhisper

Semi-Pro
Just wanted to drop a note of very special thanks to you Jack for these write ups, they are so interesting and helpful. I settled on gut/mosquito bite for most of last season based on this thread, but always enjoy some experimentation. I have a set of ZX and will give it try too. Can't wait for the final chapter...
 

Racer41c

Professional
( 118.3 ) ( 39.0 ) ( 0.088 ) .. Ashaway MonoGut ZX 16 Nylon/Zyex

Chicagojack, regarding the above set up, what is your finding? I see it underlined but greyed out so not sure if you have tried.

I am using ZX main Gosen SG cross 54/53. Last night I played one hour on indoor clay and I lost to someone I shouldn't have. This was the fourth hour of the setup. In the first three hours it played great. But yesterday the ball started to fly long a lot. I am puzzling whether it was because I haven't played on clay the whole winter or the string bed is starting to loosen up too much.

Exactly why I don't use that string for a cross any longer.
 

Racer41c

Professional
Hi Chicago, thanks for the write-ups!

If you have a minute, can I ask you about the gut you've chosen? Can you characterize the Wilson Gut?

Also, do you find that the different cross strings affect volleying?
 

ChicagoJack

Hall of Fame
( 118.3 ) ( 39.0 ) ( 0.088 ) .. Ashaway MonoGut ZX 16 Nylon/Zyex

Chicagojack, regarding the above set up, what is your finding? I see it underlined but greyed out so not sure if you have tried.

I am using ZX main Gosen SG cross 54/53. Last night I played one hour on indoor clay and I lost to someone I shouldn't have. This was the fourth hour of the setup. In the first three hours it played great. But yesterday the ball started to fly long a lot. I am puzzling whether it was because I haven't played on clay the whole winter or the string bed is starting to loosen up too much.

Oh cool, Hi Moonballs, good to see you back here again.

1. The Grey Font just means it's not a poly string. One of the things I discovered while fishing around for low friction string, is that there were (surprisingly) quite a few non-poly strings with friction digits in the poly neighborhood, with lower stiffness and better tension maintenance. So I gave them a special pass into my short list of demo options. I've updated the list so that's more clear, thanks!

2. I've just updated the thread with my experience regarding Gut/Zx. I'll have a few comments about a full bed of the stuff within the next few days. In short, it's become my go to choice for rainy conditions when I need a back up racquet with no gut.

3. I've not tried Zx as a main with syn gut crosses . But I will hazard a wild guess on what might be happening with that combination. Any string that is nylon based ... with either construction method, mono construction (ie syngut) or a multifilament construction is going to fray pretty quickly. So, you've got the slippery Zx mains sliding across the not so slippery crosses, and that's going to mean they get beat up pretty quickly. Safe to assume that the mains wont be sliding as freely with that set up on hour 6 as it is on hours 1-3. This scenario might be creating less spin. Couple that with loss of tension, and you have two reasons why you might be spraying a few more balls long over the baseline. I'm always hesitant to blame a loss of mine on my equipment, and I'm sure you are too, but tennis is a game of inches, and I know these little things can add up within the much more important context of good days and bad days for both me and my opponent.

-J
 
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ChicagoJack

Hall of Fame
Hey CJ, are you getting Cofocus spin out the ZX hybrid? Also, are your racquets 16x19?

1. I wish it were not so, but I cannot deny that a full bed of textured poly adds noticeable additional bounce height on my kick serves versus any other kind of string. For this one stroke, full poly seems unbeatable. For groundies, All the Gut/poly's I've tried are pretty spinny, the differences perceptible, but they are pretty slight. On groundies, Gut/Zx is right there with the best Gut/Polys in terms of spin, plus it's more comfortable, and has much better tension maintenance. I'm using the 16 x 19 version of the Pro One 97.

2. I will add that one of the things about judging spin potential on the court without any instrumentation is that we tend to use ball trajectory and flight path as our key indicators. I've no clue if the ball is spinning at 2,000 rpms, or if it's traveling at 2,400 rpms. This would be the truest indicator of spin, and I have to remind myself not to get too caught up in the realm of spin fantasy, because I know human body isn't sensitive enough to measure these things really accurately. That's not to say we cant do our best to make educated guesses and trust our instincts about such things. What I do know for sure is that Gut/co-focus gives you a higher rebound angle than Gut/zx. Higher over the net is going to give the impression to many that it's really spinny. The Gut/zx will have the ball pop off the racquet face with a much lower trajectory (and this takes some getting used to). But the ball seems to really dive at the last minute the same way it does with Co-focus as a cross.

3. I also tend to hit shorter into the court with Gut/Zx, than with any other hybrid. That in turn has me making a technique adjustment which is favorable to spin. With less fear of hitting long I swing a bit more freely and with more racquet head speed. It just seems like I can't miss with this stuff. On the other hand, When the ball flies higher over the net, (as it does with co-focus) the technique adjustment you are likely to make is to close the racquet face. This in and of itself will increase spin. So each string will probably prompt the player into stroke adjustments which will promote spin, but will do so in very different ways.

4. One of the things I notice with the spinny set ups like full beds of Black Widow, or Gut/Co-focus is that spin generation when you contact dead center is really awesome, but when you are early, and you catch the ball closer the the leading edge of the string bed, the ball sometimes wobbles out of the bed without much spin and sails long. When you miss the leading edge, miss the center sweet spot, but catch that bottom side of the string bed, top spin can be really awesome, but the ball might pop of pretty slow and will barely clear the net. With Gut/zx, these differences are not so great with slight timing errors and slight off center hits. I have the sensation that the string bed response is much more even, predictable and consistent, especially with the slight mishits. Control is a concept that means different things to different players, but this aspect clearly adds up to a feeling of increased control for me.

-J
 
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moonballs

Hall of Fame
Chicagojack thanks for the answer. I did notice the synthetic gut got rough in the first hour but even now the ZX is still smooth and shiny. Interestingly the crosses are slightly notched and the ZX is not.
 

corners

Legend
Chicagojack thanks for the answer. I did notice the synthetic gut got rough in the first hour but even now the ZX is still smooth and shiny. Interestingly the crosses are slightly notched and the ZX is not.

Hey Jack, speaking of notches, how do ZX mains hold up in full beds? Does ZX notch like a poly? I seem to remember in the early days of our heated ZX discussion sessions that it was discovered that Zyex, as a material, has a very high melting point, suggesting that it would tend to be notch resistant. Have you found it so?

I've got a bunch more questions for you, too. I'll post them tomorrow.
 

moonballs

Hall of Fame
The ZX/SG hybrid is the first ZX string I played. I meant to try it for a while but I took some time off tennis before winter then the long winter came. I seem to remember people saying the ZX notched similar to a soft co poly. Let's wait for jacks post on the full bed ZX.
 

MachiA.

Banned
Some people around me are playing the new
PRO'S PRO ISTRING SUPER SOFT, full bed.

Slippery and very very soft.

BigT should sell it for the US-americans.

Maybe too cheap for you, around 50 bucks a reel.

KR
 

corners

Legend
Some people around me are playing the new
PRO'S PRO ISTRING SUPER SOFT, full bed.

Slippery and very very soft.

BigT should sell it for the US-americans.

Maybe too cheap for you, around 50 bucks a reel.

KR

Any other Pro's Pro strings you think stack up well with mainstream (expensive) offerings? Heard anything about Blackforce (supposedly RPM Blast clone)?
 

bertrevert

Legend
1. I'm using the 16 x 19 version of the Pro One 97.

Immense thread - great read! - thanks

Would you be able to extrapolate your findings to how this combo would perform in one of the recent Spin racquets, the ones with fewer crosses?

(been trying all sorts of poly as best in a Spin frame however also have TE)

ps any difference between the red or the natural ZX?
 

MachiA.

Banned
Any other Pro's Pro strings you think stack up well with mainstream (expensive) offerings? Heard anything about Blackforce (supposedly RPM Blast clone)?

Black=blast, i hear that often.

Without a doubt Red Devil = red code.

People are saying it to me all the time.

I tried red devil in a full bed once, sick spin, for me too much.

Keeps playable a long time.

Balls from my opponent were landing into the t-zone, i could put them away even shorter with nice angles and very, very much TS.

Since i am not the TS player, nothing for me in the long run.

KR
 

ChicagoJack

Hall of Fame
Chicagojack thanks for the answer. I did notice the synthetic gut got rough in the first hour but even now the ZX is still smooth and shiny. Interestingly the crosses are slightly notched and the ZX is not.

Hey Jack, speaking of notches, how do ZX mains hold up in full beds? Does ZX notch like a poly? I seem to remember in the early days of our heated ZX discussion sessions that it was discovered that Zyex, as a material, has a very high melting point, suggesting that it would tend to be notch resistant. Have you found it so? I've got a bunch more questions for you, too. I'll post them tomorrow.

Hi Corners, MoonBalls - Regarding notching on full beds of Zx and Gut/Zx, see my recent review updates, March 18-19, Post #163. I've made mention of this for you two.

Immense thread - great read! - thanks Would you be able to extrapolate your findings to how this combo would perform in one of the recent Spin racquets, the ones with fewer crosses?(been trying all sorts of poly as best in a Spin frame however also have TE) ps any difference between the red or the natural ZX?

Hi BertEvert - I've not tried the wheat version, so can't compare. You can prolly find comparison on the difs btwn the two somewhere in corner's thread on zx. I think Torres might have compared the two somewhere in there. Regarding your other questions, extrapolating wild guesses based on the research of folks much smarter than I am is my specialty! I'll post my thoughts asap.
 
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ChicagoJack

Hall of Fame
I tried the 17g as a cross with gut. There was a noticeable buzz while hitting. Anyone experience this?

Hi Pig Pen - Compared to Full Poly or Gut/Poly (my usual set ups) I've not noticed an increased buzz on impact with either full beds of Zx, or Gut/zx. I'm actually sensing decreased vibration on mishits. I'll add that my racquets are very damp and comfy feeling to begin with (solid core). But I've got 9 identical frames, and I'm switching back and forth frequently, looking for little difs between all these strings.

However, I never doubt that people feel what they say they feel. When you hit center the vibration is pretty minimal regardless of strings. When you mishit, especially near the tip, vibrational frequencies vary quite a bit string to string. I think people get accustomed to feeling certain frequencies which might explain why the same strings can feel comfy to one player and harsh to the next.

-Jack

Hi Chicago, thanks for the write-ups! If you have a minute, can I ask you about the gut you've chosen? Can you characterize the Wilson Gut?Also, do you find that the different cross strings affect volleying?

Hi Racer41c - Honestly, I don't play full gut, and I've been switching out the crosses focusing on finding the GOAT cross, so the differences between brands are not so apparent to me. For mains, I'm quite happy with either Wilson Natural, Babolat Tonic, Or Babolat VS. I've had bad experiences with premature snapping with cheaper offerings from Klip and Pacific. I have a buddy who is a Rep, so I'll just buy 5-6 bags of whatever he's got the best pricing on from either of those three. Now that I've got my crosses figured out, maybe it's time to keep my crosses consistent and demo a bunch of different guts side by side. That would be expensive, might be worth the investment. I'm getting so happy with my equipment lately I'm running out of things to demo!

In terms of volleys, I like fully poly the least for sure. Next would be Gut/Poly, but I sense that the gauge and the tension of the poly crosses is a bigger factor than brand or model. Seems like higher tensions, and thicker gauges work better at net, while thinner and looser work better for baseline bashing and serving. I like more action & spin from the baseline, but favor more precision and consistent response at net. My favorite set up for me at net (btw I'm a doubles specialist on several USTA teams so I do spend some quality time up there) is the Gut/zx. I sometimes float my volleys a bit long when i'm trying to punch em deep, they are dropping into the court a bit more naturally now. Touch is really good and am able to create soft angles too. Just feels better for sure.

-Jack

Just wanted to drop a note of very special thanks to you Jack for these write ups, they are so interesting and helpful. I settled on gut/mosquito bite for most of last season based on this thread, but always enjoy some experimentation. I have a set of ZX and will give it try too. Can't wait for the final chapter...

Hi Pbarrow - Thanks. Yeah, Gut/Mosquito Bite is pretty awesome. It's was a pretty big switch for me to Gut/Zx, but well worth it for me in the long run. I've been playing with poly off and on since 1998. I remember a few of my fave pros start to use this new stuff, and I was asking for it before many of the pro shops here even had it in stock LOL. 2002-2006, I was hitting 5 days a week, two hours a day, playing with Kevlar strung in the low 60's and my arm was just fine and dandy. As I'm getting older, string and racquet comfort have become more important to me. Last 5-6 years, I've seen poly as a necessary evil, happy with the on court results, but not so happy with the health consequences. I feel like I don't have to bargain with that devil anymore. It's a big switch, and not right for everybody, but it's right for me.

-Jack
 
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corners

Legend
Notching : Corners has asked about notching, and that's one thing that has stood out for me. It seems pretty notch resistant, at least compared to the full poly poly I have ( Dunlop Black Widow 18 ) that was strung on the same day. It's difficult to keep track time I have on each of my 9 test frames, but for sure have more time on my full Zx set up than I do than full poly. The Black Widow is showing U shaped notches, and the Zx is showing just the faintest dent, really more like faint creases where you can see where the string would sit, with no abrasion at all. On the Gut/Zx string bed, the Zx is pretty smooth, even smoother than the full bed. You can see the faintest crease mark where the string would sit, but that's about it.
Jack, thanks for taking the time to add this note. Very interesting. Sounds like ZX resists notching well in a full bed and ZX crosses resist denting in a hybrid with gut mains. How about denting of the crosses in full bed ZX? I recall that Torres was finding some denting or scoring of the crosses with a full bed. He blamed this for the drop off in spin he noticed at the ten hour mark or so, the hypothesis being that the denting or scoring was impeding the mains from freely sliding. Have you noticed anything like this (denting, scoring and/or spin cliff) with a full bed?

And even so, it sounds like this is not a problem with gut/ZX. Have you noticed any change with gut/ZX over time in spin potential, launch angle or strings getting stuck out of line?


Ah, I remember one of the questions I wanted to ask you: It was interesting to read your comments about ZX not feeling as soft as its very low stiffness figures would have us anticipating. I think other play testers also found this to be the case. That low stiffness measurement would also lead to the prediction that ZX is quite a "powerful" string. Do you think it is? Some of your comments about it in your last couple posts make me wonder.
 

mikeler

Moderator
Jack, thanks for taking the time to add this note. Very interesting. Sounds like ZX resists notching well in a full bed and ZX crosses resist denting in a hybrid with gut mains. How about denting of the crosses in full bed ZX? I recall that Torres was finding some denting or scoring of the crosses with a full bed. He blamed this for the drop off in spin he noticed at the ten hour mark or so, the hypothesis being that the denting or scoring was impeding the mains from freely sliding. Have you noticed anything like this (denting, scoring and/or spin cliff) with a full bed?

And even so, it sounds like this is not a problem with gut/ZX. Have you noticed any change with gut/ZX over time in spin potential, launch angle or strings getting stuck out of line?


Ah, I remember one of the questions I wanted to ask you: It was interesting to read your comments about ZX not feeling as soft as its very low stiffness figures would have us anticipating. I think other play testers also found this to be the case. That low stiffness measurement would also lead to the prediction that ZX is quite a "powerful" string. Do you think it is? Some of your comments about it in your last couple posts make me wonder.


All strings will notch eventually. ZX does not feel at all like gut but on the stringing machine it stretches like gut. It feels like a very powerful poly.
 

ChicagoJack

Hall of Fame
Jack, thanks for taking the time to add this note. Very interesting. Sounds like ZX resists notching well in a full bed and ZX crosses resist denting in a hybrid with gut mains. How about denting of the crosses in full bed ZX? I recall that Torres was finding some denting or scoring of the crosses with a full bed. He blamed this for the drop off in spin he noticed at the ten hour mark or so, the hypothesis being that the denting or scoring was impeding the mains from freely sliding. Have you noticed anything like this (denting, scoring and/or spin cliff) with a full bed?

And even so, it sounds like this is not a problem with gut/ZX. Have you noticed any change with gut/ZX over time in spin potential, launch angle or strings getting stuck out of line?

Hi Corners -

Short Answer : The strings are not stuck out of line in either the Gut/Zx, or the full bed of Zx, and I've noticed no drop off in spin yet. But the way that you have precisely worded your question, has had me go back and look for signs of wear in my full bed again.

[..]

State Of The Crosses, Full Bed Zx: If I slide the mains (left to right) over the crosses, I continue see no signs of notching or abrasion on the Xs, just a very faint crease mark where the main would normally sit.

State Of the Mains, Full Bed Zx: However, when I swing the crosses (north to south over the mains, not something I usually do) I can feel that it takes more effort to displace the crosses. I can also now there are u shaped notches in the mains, that the crosses have to climb out of.

The Net Effect : Is that both Ms and Xs will still slide freely enough to snap back to neutral, when I pluck them like guitar strings. The notches in the mains make it harder to displace the crosses, and there's a lot more creaking and complaining from the strings on that test. When examining for string wear, I'm not normally swinging my crosses north to south because that's kind of a non-factor regarding spin enhancement, that's why I missed this the first time around.

This has me wondering: One of the key benefits of Gut mains is that you have more certainty about the composition of the inside of the string versus the outside. It's gut on the outside, and gut on the inside. Maybe there's a thin coating on top that the marketing departments will make a big deal about, but gut is gut for the most part. Perhaps its a good thing that Zx is not a multi but a mono construction, so we can have a bit more certainty about its interior COF properties. TW Professor has proposed a plausible hypothesis that might explain explain the low COF of Gut/Poly. That is that the gut will secrete natural oils as it notches, creating a sort of lubricated rail system over the slippery poly Xs. Probably safe to assume that as far as Zx is concered, it wont be secreting any natural oils as it ages.

So... what is the effect on spin, when the mains notch on a full bed of Zx? Although I've not noticed it yet, my intuitive guess is that you'll get more spin with a fresh set, and spin will gradually decrease. It's the same old conundrum we are left with when we string with poly. It plays better when it's fresh, nobody disputes that. I wish I'd kept better records for how many hours I have on each test frame, but I'm comfortable saying Gut/Zx ages pretty well, with better tension maintenance compared to most Gut/poly. I will state for the record there are a handful of recent poly offerings with better tension maintenance than Zx, (LTec, Lux 4G, RPM Blast, and a few others). But all of these offerings are exceptionally stiff, and so those options are not on the table for me. When comparing the aging process of full beds of Zx to Full Poly, Zx has a clear advantage with regards to tension versus the average poly. And my early evidence is that Zx is at least even money on notching, abrasion, and possibly more notch resistant. It's something I'll keep a close watch on going forward.

-Jack
 
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corners

Legend
Hi Corners -

Short Answer : The strings are not stuck out of line in either the Gut/Zx, or the full bed of Zx, and I've noticed no drop off in spin yet. But the way that you have precisely worded your question, has had me go back and look for signs of wear in my full bed again.

[..]

State Of The Crosses, Full Bed Zx: If I slide the mains (left to right) over the crosses, I continue see no signs of notching or abrasion on the Xs, just a very faint crease mark where the main would normally sit.

State Of the Mains, Full Bed Zx: However, when I swing the crosses (north to south over the mains, not something I usually do) I can feel that it takes more effort to displace the crosses. I can also now there are u shaped notches in the mains, that the crosses have to climb out of.

The Net Effect : Is that both Ms and Xs will still slide freely enough to snap back to neutral, when I pluck them like guitar strings. The notches in the mains make it harder to displace the crosses, and there's a lot more creaking and complaining from the strings on that test. When examining for string wear, I'm not normally swinging my crosses north to south because that's kind of a non-factor regarding spin enhancement, that's why I missed this the first time around.

This has me wondering: One of the key benefits of Gut mains is that you have more certainty about the composition of the inside of the string versus the outside. It's gut on the outside, and gut on the inside. Maybe there's a thin coating on top that the marketing departments will make a big deal about, but gut is gut for the most part. Perhaps its a good thing that Zx is not a multi but a mono construction, so we can have a bit more certainty about its interior COF properties. TW Professor has proposed a plausible hypothesis that might explain explain the low COF of Gut/Poly. That is that the gut will secrete natural oils as it notches, creating a sort of lubricated rail system over the slippery poly Xs. Probably safe to assume that as far as Zx is concered, it wont be secreting any natural oils as it ages.

So... what is the effect on spin, when the mains notch on a full bed of Zx? Although I've not noticed it yet, my intuitive guess is that you'll get more spin with a fresh set, and spin will gradually decrease. It's the same old conundrum we are left with when we string with poly. It plays better when it's fresh, nobody disputes that. I wish I'd kept better records for how many hours I have on each test frame, but I'm comfortable saying Gut/Zx ages pretty well, with better tension maintenance compared to most Gut/poly. I will state for the record there are a handful of recent poly offerings with better tension maintenance than Zx, (LTec, Lux 4G, RPM Blast, and a few others). But all of these offerings are exceptionally stiff, and so those options are not on the table for me. When comparing the aging process of full beds of Zx to Full Poly, Zx has a clear advantage with regards to tension versus the average poly. And my early evidence is that Zx is at least even money on notching, abrasion, and possibly more notch resistant. It's something I'll keep a close watch on going forward.

-Jack

Thanks for your detailed reply, Jack!

Your comments about ZX in this thread have me seriously considering just going ahead and buying a reel of it. I've got a bunch of racquets I'm going to test soon and I was thinking of stringing them all with a cheap soft poly for consistency, as I can't afford to do them all with gut/poly. After picking a winner and getting multiple frames of it, I planned to move on to string tests.

But maybe I should just bite the bullet and string them all with ZX. If it really comes down to ZX being even money on notching and spin, but better in tension stability, power and comfort…well, that's essentially what I'm looking for so why not start there. After I've picked my new stick I can then split hairs between full ZX, gut/ZX and gut/poly.

I feel the same as you about the newer tension-stable polys like 4S. Too stiff even with gut mains for me, or so I fear. Gotta play it smart with aging arms. Another thing about these stiff, tension-stable guys is that they are also the polys with the greatest energy return, according to TWU. It's generally so that the soft copolys have low energy return and poor tension stability, while the stiffer ones have high energy return and better tension stability. There are a handful of newer strings - like Head Hawk - that appear, from the TWU numbers, to be finally combining relatively low stiffness, notch resistance, high energy return, super-lower inter-string friction and tension stability. But sounds like ZX ticks all those boxes pretty well while being more flexible than any poly.

One place I plan to try 4S, though, is in the crosses of a Pro Staff 95S with gut mains. I'm hoping that the low number of crosses will make the stiff 4S play softer than it would in a conventional pattern. This combo will also test the "flat crosses act as string savers with gut mains" hypothesis. If it passes the test it would be pretty awesome, but I doubt it will. :)
 

ChicagoJack

Hall of Fame
There in the first link, string friction from TW, why is there two friction values for the string: Pacific X Force 17?

Hi CHOcobo -

Friction is the outer column on the far right. What I'm seeing for Pacific X Force 17 is this .... 246.9 | 89.3 | 0.081

246.9 = Stiffness
89.3 = Energy Return
0.081 = Coefficient Friction
 
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ChicagoJack

Hall of Fame
Thanks for your detailed reply, Jack!

Your comments about ZX in this thread have me seriously considering just going ahead and buying a reel of it. I've got a bunch of racquets I'm going to test soon and I was thinking of stringing them all with a cheap soft poly for consistency, as I can't afford to do them all with gut/poly. After picking a winner and getting multiple frames of it, I planned to move on to string tests.

But maybe I should just bite the bullet and string them all with ZX. If it really comes down to ZX being even money on notching and spin, but better in tension stability, power and comfort…well, that's essentially what I'm looking for so why not start there. After I've picked my new stick I can then split hairs between full ZX, gut/ZX and gut/poly.

I feel the same as you about the newer tension-stable polys like 4S. Too stiff even with gut mains for me, or so I fear. Gotta play it smart with aging arms. Another thing about these stiff, tension-stable guys is that they are also the polys with the greatest energy return, according to TWU. It's generally so that the soft copolys have low energy return and poor tension stability, while the stiffer ones have high energy return and better tension stability. There are a handful of newer strings - like Head Hawk - that appear, from the TWU numbers, to be finally combining relatively low stiffness, notch resistance, high energy return, super-lower inter-string friction and tension stability. But sounds like ZX ticks all those boxes pretty well while being more flexible than any poly.

One place I plan to try 4S, though, is in the crosses of a Pro Staff 95S with gut mains. I'm hoping that the low number of crosses will make the stiff 4S play softer than it would in a conventional pattern. This combo will also test the "flat crosses act as string savers with gut mains" hypothesis. If it passes the test it would be pretty awesome, but I doubt it will. :)

Hi Corners - I don't know if you are still on the fence about buying a reel of Zx... but I'd be interested in purchasing the remainder of what's left over if you try it and then find you don't like it. Seems like we've been honing in on crosses with the same attributes (Low COF, good tension maintenance, low stiffness) for quite a while now. If you find something that ticks all those check boxes even better than Zx please let me know!
 
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tacotanium

Professional
Hi CHOcobo -

Friction is the outer column on the far right. What I'm seeing for Pacific X Force 17 is this .... 246.9 | 89.3 | 0.081

246.9 = Stiffness
89.3 = Energy Return
0.081 = Coefficient Friction

Oh...geez..... I know, I've been reading tables like this since 5th grade. My point was there are two different values for this same string on the table. That means there is this in the table:

Pacific X Force 17 .... 246.9 | 89.3 | 0.081
Pacific X Force 17 .... 246.9 | 89.3 | 0.099

Which one is the real one?
 

ChicagoJack

Hall of Fame
Oh...geez..... I know, I've been reading tables like this since 5th grade. My point was there are two different values for this same string on the table. That means there is this in the table:

Pacific X Force 17 .... 246.9 | 89.3 | 0.081
Pacific X Force 17 .... 246.9 | 89.3 | 0.099

Which one is the real one?

I have no idea why you are asking me, but yeah ... I see it now, that's a good catch. This is most likely a data entry error. In my book the difs btwn those two are so slight it's not worth worrying about. However, if you are really determined to find which digit is correct, you could always go to the TW Questions / Comments Section of the board, and direct the question to the TW Professor.

-J
 
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Maui19

Hall of Fame
CJ--thanks for all the great info and the time you spent to share it with us.

I want to give the ZX a try--my current go-to setup is gut/Pro Line II. Can someone talk about the difference between ZX and ZX Pro? Also, my crosses are currently 17g. Any reason I should change that with ZX?

Thanks!
 

corners

Legend
Hi Corners - I don't know if you are still on the fence about buying a reel of Zx... but I'd be interested in purchasing the remainder of what's left over if you try it and then find you don't like it. Seems like we've been honing in on crosses with the same attributes (Low COF, good tension maintenance, low stiffness) for quite a while now. If you find something that ticks all those check boxes even better than Zx please let me know!

Hey CJack, I'm gonna send you a PM later today or tomorrow. Cheers
 

SpinToWin

Talk Tennis Guru
what a bomb of a thread, amazing read that makes me want to go gut main immediately (I think I'll have to wait till I'm out of university though, student budget is not all too high :cry: )! What made me curious is that Head Hawk has the lowest friction according to the data (as far as I can see). I've played the string before and quite liked it, however, paired with the power, comfort and touch of natural gut, I think I'd love it. Has anybody tried this specific setup and if yes, how was it? Also, which gauge of gut/poly would you recommend? Or is there a reason why this set up would not work? Sorry for bombarding you with questions, but I'm new to the world of natural gut (as you probably realize). :D
 

SpinToWin

Talk Tennis Guru
CJ--thanks for all the great info and the time you spent to share it with us.

I want to give the ZX a try--my current go-to setup is gut/Pro Line II. Can someone talk about the difference between ZX and ZX Pro? Also, my crosses are currently 17g. Any reason I should change that with ZX?

Thanks!

Could you tell me how your gut and pro line II hybrid plays? :)
 

corners

Legend
what a bomb of a thread, amazing read that makes me want to go gut main immediately (I think I'll have to wait till I'm out of university though, student budget is not all too high :cry: )! What made me curious is that Head Hawk has the lowest friction according to the data (as far as I can see). I've played the string before and quite liked it, however, paired with the power, comfort and touch of natural gut, I think I'd love it. Has anybody tried this specific setup and if yes, how was it? Also, which gauge of gut/poly would you recommend? Or is there a reason why this set up would not work? Sorry for bombarding you with questions, but I'm new to the world of natural gut (as you probably realize). :D
Do it. Do it. Everything known suggests it is the bomb. (No, I haven't tried it.)
 

ChicagoJack

Hall of Fame
by the way… How in the world does Kirschbaum Spiky Shark have the lowest coefficient of friction :confused:

I know right? One of the things that Crawford Lindsey aka, TW Professor discovered while performing these sliding friction and spin tests, is that there are some results which are quote ... "especially interesting". I'd say there are some results which are downright anti-intuitive. Kirschbaum Spiky Shark does have the lowest COF of any full bed of poly on record at 0.068, [1] with Solinco Outlast and Isospeed Black Fire, close behind at 0.069. That is for sure an unexpected result. Link [1] http://twu.tennis-warehouse.com/learning_center/COFreporter.php

However, what was even more surprising, is that the lowest COF overall title belongs not to a full bed of smooth poly. The lowest COF on record belongs to Gut mains and MSV Hepta-Twist 17 at 0.059. [1] I'm fairly certain nobody would have predicted gut mains and twisted, edged, poly would create the lowest friction of out of hundreds of strings and string combinations that were tested. Also fascinating to me is that when you reverse the hybrid, Poly/Gut has amongst the highest COF digits. Here's what the TW Professor has to say about these sometimes surprising results:

Quote 1 : "It is interesting how materials behave differently individually and in combination. It is especially interesting how a particular combination of a main and a cross can behave totally differently when the string types are reversed into the cross and the main. In this case you would assume that the adhesion forces are the same and the shape of the contacting surfaces are the same. So it seems that the relative deformation between main and cross is what matters in the differing movement between the strings for a hybrid and reverse hybrid. Though many combinations are possible a couple types of deformation seem likely as most important. If the cross is softer than the main, the main will sink into the cross. To initiate movement along the cross, the main will first have to climb a hill out of the valley it sits in, but also it will have to continually plow its way forward as it moves and sinks down the length of the cross. If the cross is a multifilament or multistrand string, it can also fray and break filaments. These can stick up as obstacles, hooks, or spikes that can slow movement over them. If the main is softer than the cross, it will deform over the cross such that it forms a slot or groove to move over the cross. That may actually facilitate movement, especially if the deformation causes a leakage of some oil, lubricant, etc. from inside the string.
-- Sliding Friction And Spin
http://twu.tennis-warehouse.com/learning_center/slidingCOF.php

Quote 2 : " It is very interesting that the hybrid with poly crosses and gut mains is the combination with the lowest static COF. What is equally interesting is that if you change the combination to gut crosses and polyester mains, the static coefficient of friction is among the highest. Two hypotheses arise to explain these. First, if the cross is softer than the main, the main will sink into the cross. To initiate movement along the cross, the main will first have to climb a hill out of the valley it sits in, but also it will have to continually plow its way forward as it moves and sinks down the length of the cross. If the main is softer than the cross, it will deform over the cross such that it forms a slot or groove to move over the cross. That may actually facilitate movement, especially if the deformation causes a leakage of some oil, lubricant, etc. from inside the string. Second, if the cross is a multifilament or multistrand string like gut, it can also fray and break filaments as the polyester main moves up and down over its length. These broken filaments can stick up as obstacles, hooks, or spikes that can prevent or slow movement over them. "[/B]
-- Static Friction and Spin
http://twu.tennis-warehouse.com/learning_center/COF.php
 
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ChicagoJack

Hall of Fame
CJ--thanks for all the great info and the time you spent to share it with us.

I want to give the ZX a try--my current go-to setup is gut/Pro Line II. Can someone talk about the difference between ZX and ZX Pro? Also, my crosses are currently 17g. Any reason I should change that with ZX?

Thanks!

Hi Maui, NP. I've no experience with either ZX pro or Pro Line II. I'm bumping your question for you, hopefully somebody can chime in.

-J
 

ChicagoJack

Hall of Fame
what a bomb of a thread, amazing read that makes me want to go gut main immediately (I think I'll have to wait till I'm out of university though, student budget is not all too high :cry: )! What made me curious is that Head Hawk has the lowest friction according to the data (as far as I can see). I've played the string before and quite liked it, however, paired with the power, comfort and touch of natural gut, I think I'd love it. Has anybody tried this specific setup and if yes, how was it? Also, which gauge of gut/poly would you recommend? Or is there a reason why this set up would not work? Sorry for bombarding you with questions, but I'm new to the world of natural gut (as you probably realize). :D

I've not tried Head Hawk. But I do see what you are seeing, the digits on that string stick out like a sore thumb. Very low friction, very good tension maintenance, but just too stiff for my taste. I can envision Gut/Hawk being a very spinny set-up that plays really well for a very long time. Gut/Poly is only a few bucks more expensive for me, because I'll get 30-40 hours out of it, and will clip out full poly long before it breaks. Seems like Gut/Hawk would work great in that you want a poly cross that keeps tension pretty well until the gut snaps.
 

Sander001

Hall of Fame
I know right? One of the things that Crawford Lindsey aka, TW Professor discovered while performing these sliding friction and spin tests, is that there are some results which are quote ... "especially interesting". I'd say there are some results which are downright anti-intuitive. Kirschbaum Spiky Shark does have the lowest COF of any full bed of poly on record at 0.068, [1] with Solinco Outlast and Isospeed Black Fire, close behind at 0.069. That is for sure an unexpected result. Link [1] http://twu.tennis-warehouse.com/learning_center/COFreporter.php

However, what was even more surprising, is that the lowest COF overall title belongs not to a full bed of smooth poly. The lowest COF on record belongs to Gut mains and MSV Hepta-Twist 17 at 0.059. [1] I'm fairly certain nobody would have predicted gut mains and twisted, edged, poly would create the lowest friction of out of hundreds of strings and string combinations that were tested. Also fascinating to me is that when you reverse the hybrid, Poly/Gut has amongst the highest COF digits. Here's what the TW Professor has to say about these sometimes surprising results:

Quote 1 : "It is interesting how materials behave differently individually and in combination. It is especially interesting how a particular combination of a main and a cross can behave totally differently when the string types are reversed into the cross and the main. In this case you would assume that the adhesion forces are the same and the shape of the contacting surfaces are the same. So it seems that the relative deformation between main and cross is what matters in the differing movement between the strings for a hybrid and reverse hybrid. Though many combinations are possible a couple types of deformation seem likely as most important. If the cross is softer than the main, the main will sink into the cross. To initiate movement along the cross, the main will first have to climb a hill out of the valley it sits in, but also it will have to continually plow its way forward as it moves and sinks down the length of the cross. If the cross is a multifilament or multistrand string, it can also fray and break filaments. These can stick up as obstacles, hooks, or spikes that can slow movement over them. If the main is softer than the cross, it will deform over the cross such that it forms a slot or groove to move over the cross. That may actually facilitate movement, especially if the deformation causes a leakage of some oil, lubricant, etc. from inside the string.
-- Sliding Friction And Spin
http://twu.tennis-warehouse.com/learning_center/slidingCOF.php

Quote 2 : " It is very interesting that the hybrid with poly crosses and gut mains is the combination with the lowest static COF. What is equally interesting is that if you change the combination to gut crosses and polyester mains, the static coefficient of friction is among the highest. Two hypotheses arise to explain these. First, if the cross is softer than the main, the main will sink into the cross. To initiate movement along the cross, the main will first have to climb a hill out of the valley it sits in, but also it will have to continually plow its way forward as it moves and sinks down the length of the cross. If the main is softer than the cross, it will deform over the cross such that it forms a slot or groove to move over the cross. That may actually facilitate movement, especially if the deformation causes a leakage of some oil, lubricant, etc. from inside the string. Second, if the cross is a multifilament or multistrand string like gut, it can also fray and break filaments as the polyester main moves up and down over its length. These broken filaments can stick up as obstacles, hooks, or spikes that can prevent or slow movement over them. "[/B]
-- Static Friction and Spin
http://twu.tennis-warehouse.com/learning_center/COF.php
Yes, the crosses need to be stiff like a rail so the mains are better able to slide across them.
 
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