Zhang Jike says inner carbon blades degrade faster than outer carbon blades. Why is that?

[Robin0910]

He also talks about boosting and custom sponges.

 

[igorponger]

Is it Zhike who won Olympic gold in the past years? .

 

[Dr Evil]

Possibly because the carbon composite layer shields underlying wood layers from water based glue which softens wood over time. Don't know if this is the case; hopefully one of the blade makers will comment. An inner carbon blade has two 'unshielded' wood layers vs only one for an outer carbon blade, so may soften and lose stiffness faster.

 

[wiktor145]

I would also guess, that all that powerfull shots cause the blades to constantly deform and flex. Maybe this causes some micro tears and damage inside wood veneers. And as outer carbon theoretically should be less flexible than inner (not sure if that is true, but that feels true), this could happen quicker?

Someone like Zhang Jike could have the power needed for that to happen, but if we, mere mortals, would be able to generate such power - not sure. Maybe it would take us much longer. Playing frequency and "shots per day" could also have an impact here.


But the glue hyphotesis seems also very true. Pro's change rubbers quite a lot so the damage could also be faster.

 

[Zwill]

I think he only says that because traditionally (and especially Chinese) use Viscaria, TB ALC as outer carbon blade with koto top ply, while the inner carbon blades are traditionally limba outer plies from DHS or Innerforce ALC, ZLC etc. I realize there are koto top plied inner carbon blades but during ZJK time that was not very popular.

Koto blades usually tend to endure the re-glueing and especially the peeling off of rubbers better while limba less so.

There might be something in that outer carbon blades are stiffer and lose that property later but on the other hand innercarbon blades tend to have a harder core ply.

 

[banbekas]

He's pulling it out of his butt. He's weaving truths and lies to create an interesting narrative about blade; it's not like someone can actually disprove his conjecture. There are many variables that affect blade's durability after all and too little time to research it one by one.

He's putting himself as someone of power due to his achievements and skill, which is not wrong, and by throwing that narrative, more gullible TT players will come and watch his livestream. A classic marketing strategy.

He keeps saying blade is this and that and pick one that feel is suitable for you. We all know that this is true. That his blade is custom made for him. He liked the old Viscaria and the current version is something he's unfamiliar with coz he never uses it. I'm inclined to believe that this is somewhat a lie. Then came the million dollar statement, the red one is the most similar to what he has used. He implies that Donic ZJK is very similar to what he uses, buy it if you want the touch of ZJK!

I know this but I still want that ZJK's touch. lol

 

[Andy_YEO]

He is a Chinese authority in this context - I guess this is how it has to sound when he directs his subjects, endless debates of which blade to use wont help anyone. He failed to mentioned that most chinese coaches recommend Stiga Clipper though.

His channel is invaluable for learning technique though, best complement to the skills that Pingskills offer there is.

 

[andzejgolot]

I think he knows how fast Ma Long and top tier players destroy the tension from w968 and blade start to be weird and remember how his viscaria didnt change performance too much

 

[Egon]

Not only Zhang Jike, but also Timo Boll, spoke about the fact that professionals wear out their blades.
Regarding the speed of blade wear, Zhang Jike's opinion, also makes sense, since blades with internal carbon bend more than blades with external carbon. This is due to the moment of inertia or the moment of resistance, since blades with external carbon have layers of hard carbon located further from the blade axis therefore they are more rigid and bend less. Accordingly, the blade that bends more will wear out faster.

 

[Tyce]

Maybe a blade maker can chime in, but I think the interface between the fiber layer and wood layers is the important part. As the epoxied fiber is significantly more rigid than wood, a hard impact will cause micro cracks in this interface since the wood bends much more.

To a certain level, all wood is less susceptible to this since the layers are much closer to each other in properties.

As to why this happens more on inner fiber blades... I don't know. Maybe it has something to do with the wood grain direction, having the medial layer on top of the fiber pulls on it in the lateral direction? Or the impact deforms the blades top layers more in both longitudinal and lateral directions, where an impact on the outer layer alone would generate mostly longitudinal deformation?

 

[Wakkibatty]

Maybe a blade maker can chime in, but I think the interface between the fiber layer and wood layers is the important part. As the epoxied fiber is significantly more rigid than wood, a hard impact will cause micro cracks in this interface since the wood bends much more.

To a certain level, all wood is less susceptible to this since the layers are much closer to each other in properties.

As to why this happens more on inner fiber blades... I don't know. Maybe it has something to do with the wood grain direction, having the medial layer on top of the fiber pulls on it in the lateral direction? Or the impact deforms the blades top layers more in both longitudinal and lateral directions, where an impact on the outer layer alone would generate mostly longitudinal deformation?

Ding! ding! ding! -- we have a winner folks... (...well kind of... I think 😂).

Honestly speaking, I can't say I've noticed this particular phenomenon myself as a player, as I haven't ever used an inner-composite blade to the point of failure. 🤔🤔 Nor have I ever had a customer or sales rep complain to me before about the life of inner carbon construction blades being generally shorter than that of an outer carbon equivalent (regardless of the brand, type or manufacturer).

What I *can* confirm however is that (generally speaking - as @Tyce correctly points out) there's a potentially higher than normal risk of separation / cracking / delamination problems occuring whenever you try to laminate extremely hard, stiff and inflexible material (such as some modern composite fabrics) directly onto very soft low-density wood (as is often found in your typical blade's core).

In the simplest terms possible, when building a blade, the more dissimilar two proximate materials are in a blade's composition, the more trouble you are going to experience if you also want them to move and flex together. Depending on the materials in question, and the amount of movement you ask of them, sooner or later material fatigue starts to becomes a factor,

You get around this problem by making the relative differences in material properties as small as practically possible, and by ensuring the surrounding layers are lending their support.

When planning a blade you also need to allow anisotropic material to be true to its nature. Wood is *always* going to be substantively stronger or weaker along one plane compared to others (hence the use of the term anisotropic). Sure modern composites can help add symmetrical, multidimensional stiffness to the mix, but that's still doesn't change the underlying nature of the softer weaker wood located right next to it.

In theory, as outer composite layers are typically surrounded by layers of denser harder material than you find in the core, there's a slightly smaller risk of fatigue, as mechanical forces are typically slightly better distributed throughout the layers.

TL: DR Version....

Eh... The general idea has some technical merit to it, but it all depends on the blade in question, the user, and its operating environment.

As always, mileage and/or individual user results may vary.

 

[Robin0910]

Ding! ding! ding! -- we have a winner folks... (...well kind of... I think 😂).

Honestly speaking, I can't say I've noticed this particular phenomenon myself as a player, as I haven't ever used an inner-composite blade to the point of failure. 🤔🤔 Nor have I ever had a customer or sales rep complain to me before about the life of inner carbon construction blades being generally shorter than that of an outer carbon equivalent (regardless of the brand, type or manufacturer).

What I *can* confirm however is that (generally speaking - as @Tyce correctly points out) there's a potentially higher than normal risk of separation / cracking / delamination problems occuring whenever you try to laminate extremely hard, stiff and inflexible material (such as some modern composite fabrics) directly onto very soft low-density wood (as is often found in your typical blade's core).

In the simplest terms possible, when building a blade, the more dissimilar two proximate materials are in a blade's composition, the more trouble you are going to experience if you also want them to move and flex together. Depending on the materials in question, and the amount of movement you ask of them, sooner or later material fatigue starts to becomes a factor,

You get around this problem by making the relative differences in material properties as small as practically possible, and by ensuring the surrounding layers are lending their support.

When planning a blade you also need to allow anisotropic material to be true to its nature. Wood is *always* going to be substantively stronger or weaker along one plane compared to others (hence the use of the term anisotropic). Sure modern composites can help add symmetrical, multidimensional stiffness to the mix, but that's still doesn't change the underlying nature of the softer weaker wood located right next to it.

In theory, as outer composite layers are typically surrounded by layers of denser harder material than you find in the core, there's a slightly smaller risk of fatigue, as mechanical forces are typically slightly better distributed throughout the layers.

TL: DR Version....

Eh... The general idea has some technical merit to it, but it all depends on the blade in question, the user, and its operating environment.

As always, mileage and/or individual user results may vary.

So basically koto and carbon pairs better than limba and carbon because the hardnesses are more similar to each other?

 

[Wakkibatty]

So basically koto and carbon pairs better than limba and carbon because the hardnesses are more similar to each other?

Ummmm....

(...how do I explain this)

Short answer is Well..... yeah, kinda... but equally it's also "no not really"

To answer either yes or no to that question the way it is currently worded would be hugely misleading sorry.

The similarity in properties between koto and carbon partially explains the compatibility yes, but that compatibility is also a manufactured outcome.... They are similar and compatible because the blade's designer wanted them to be that way.

When viewed purely in isolation, the properties of koto and limba are normally pretty constant and consistent (within their certain 'normal' natural range of variation) as they are both biological substances.

The properties of carbon fiber however can actually vary hugely. Carbon fiber is not one substance, but is a mix of several different ones.

The properties of carbon fiber largely spring from how it is treated during blade manufacture. Carbon fibers themselves can be hard yes, but only if you put something hard directly behind them. They have huge longitudinal strength, but no lateral strength.... they therefore have to borrow the lateral strength of other manufacturing inputs to do their job at all.

A sheet of soft carbon fleece looks like a thin sheet of black tissue paper, but it snaps and crumbles into tiny thin, needle-sharp triangular shards with the slightest side impact. Literally speaking, a pile of corn chips has more natural lateral resilience to it than carbon fiber does.

A huge number of carbon fiber's properties are actually determined by other substances and other manufacturing variables entirely, such as the type and amount of resin used in the supporting matrix, the location of the carbon layer in the blade, and the stiffness and makeup of the surrounding layers.

Both koto and limba are mid-density woods and share a roughly similar mass. And yes, Koto is a stiffer and harder wood compared to limba which is softer and far more flexible... But even that difference becomes pale by comparison when you compare either koto or limba to carbon fiber. The difference in hardness between limba and koto is small. The difference in hardness between either limba or koto however compared to carbon fiber (in its usual form) is massive, so there your parallel falls down.

When carbon fiber is typically teamed with koto, it is typically rendered into a stiff and hard form to better match the koto. So in that respect yes, they match better because of their similarities... But again that similarity is also a desired outcome outcome. Making carbon fiber team with limba the same way would be very difficult given limba's flexibility, but if you use a flexible enough resin it's theoretically possible to match them together equally well.

That said, nobody ever bothers, as it would defeat the most common main purpose of having carbon fiber, which is to add stiffness and strength without also adding too much weight.

So yes.... while the typical mechanical similarities between koto in a blade (ie both of them are 'stiff' and 'hard') does make them a good match, they only work together that particular way when the blade maker wants them to be like that. You could theoretically do the same with limba too... But you don't even bother cause it's kind of a silly idea... Limba is used for its spin and softness, not for it's ability to match carbon or vice versa.

Limba teams best with 'typical' carbon fiber layers when there's a soft medial between them... Koto teams best with 'typical' carbon fiber when there's no intervening layer. You don't *have* to do it this way in either case... you just consistently get the best result when you do.

Hoe all this helps... I don't really know if I've directly addressed your question there 🤔🤔.. It feels a bit like I talked around it frankly.

TBH it's an odd way to approach this particular subject... (We're very mch putting the cart before the horse a bit here, as the wording of your question kind of conflates causes with outcomes 🤔😂).

Probably best to say sure there is a correlation between koto and carbon being used together, land while similarities in properties can sometimes cause such correlations, here that similarity is only ever an outcome, not a precondition.

The cause of koto and carbon's correlational use is not the result of any perceived mechanical similarities between them. Any such similarity is purely an end in itself, and something that arose from entirely different logic.

 

[Egon]

So basically koto and carbon pairs better than limba and carbon because the hardnesses are more similar to each other?

I noticed that when gluing the top layer of koto, this layer is much more saturated with glue. The glue comes out and it is necessary to use polyethylene pads so that this glue does not stick to the press. The blade with the surface of the limba is less saturated with glue. If we use limba extra veneer, which is much denser, then the glue does not come out on the surface at all. Accordingly, it is much more difficult to peel off koto from the the carbon layer or other wood because the glue penetrates into the koto very deeply.

 

[ttarc]

Isn't this - to a certain extent- just because of the different playing properties (mainly speed)? Many/most(?) 1) inner carbon blades are slower on low and medium impact shots than outer carbon blades i.e. to get the same speed we need to hit harder and to get the full effect from the carbon layer we need to hit even harder. More strain on average?
Imo/what I think/feel is that inner carbon blades are more suitable for a more aggressive playing style both close and further away from the table i.e. more strain on the material and therefore will degrade faster.

1) https://ttgearlab.com/category/database/

 

[rbtitco]

Has anyone IRL felt that their outer carbon blades degrades faster than their inners? I'm not sensitive enough to tell.
I don't trust Zhang Jike, while, unquestionably, an amazing player, he's sketchy. In addition, he's selling outer carbon blades atm

 

[lodro]

Imo/what I think/feel is that inner carbon blades are more suitable for a more aggressive playing style both close and further away from the table i.e. more strain on the material and therefore will degrade faster.

I respect your opinion but i was always thinking that the aggressive hard hitters preferred the outer carbon blades with (eg.) hard Koto outer layer ???????????

 

[ttarc]

I respect your opinion but i was always thinking that the aggressive hard hitters preferred the outer carbon blades with (eg.) hard Koto outer layer ???????????

We have measurements from TTGearLab Most inner carbon blades (at least what I can get/borrow) are blades that hold the ball deep(er)/long/(er) compared to outer carbon blades and usually have a lower base speed (Ovtcharov Inner ALC being one of the exceptions to that rule) i.e. the ball leaves the blade later/the blade flexes more. This holds up to a certain limit when the deeper carbon layers kick in and the usually stronger core (inner usually use ayous vs. kiri) helps.
This deep hold helps to get the ball over the net and on the table (more spin) when attacking full power especially close to the table and with a lesser risk of overshooting (no or less need to hold back/shorten the stroke). Outer carbon blades have less margin for error in this regard but are easier to use a step or two further back i.e. when the ball comes back (less effort needed to get the ball going and more time to also get enough spin on the ball).

 

[Tony's Table Tennis]

Has anyone IRL felt that their outer carbon blades degrades faster than their inners? I'm not sensitive enough to tell.
I don't trust Zhang Jike, while, unquestionably, an amazing player, he's sketchy. In addition, he's selling outer carbon blades atm

yeah ,2 outer wood versus 1 outer wood
when you glue every 3 days, and have the feel of the elite, you would have the same conclusion.
Mens hit harder, so change faster than womens.

This kind of thread is the reason why I feel, some information is really not applicable in the amateur space.
Same as some pro charging high prices for "equipment" training.

In summary, when the blade starts to flex, it is unusable.

 

[PoppaChubby]

That's the reason why IMHO everyone should lacquer inner carbon blades, I've kept a Waldner Diablo Senso for 2 decades that way, maybe the inner glassfiber layer helped ? there's actually glassfiber fabric all over the walls in my kitchen and bathroom, it's there since at least 2 or 3 decades, they just paint over and over those walls.

All-wood blades really degrade fast, in feel, in speed, they feel really "weird" after just a few years, we all know that. The first Clipper I've tried was UBER lacquered, because of people using speed glue at that time in 1991 and everyone said it was mandatory to lacquer any all-wood blade.

For the pros, not only men: Jianan Yuan have kept her trusty Timo Boll Spirit for ages, it was not sold anymore for Europe and France so on the official BTY EU website since the introduction of the TB ALC. She replaced it with a Viscaria since only the pandemic or so. I've made a training camp in 2022's summer with a FFTT's certified coach that had still a TBS, his very first carbon blade when he was a teenager. Never used anything else. He was in his 30 in 2022.