Sponge Hardness new Video

[7sagittarius7]

Hey! Great to see you here.

According to the conversion charts, H3 40 should be 54d on ESN scale. But when you measured it, it showed 58d after boosting. Why would it be so much harder than the conversion chart says?

I will repeat the measurement on a different rubber, maybe something was wrong with this one. I am waiting for the personal rubber from Chen Meng to arrive, also 40d. And some more Loki and Victas rubbers, so I will measure them as well. I will let you know how much I measure on the Chen Meng rubber before any gluing or booster.

 

[zeio]

I also found information that DHS uses Shore A, Butterfly uses Asker E, and ESN uses Asker C.

For the curious minds on the different hardness scales and why conversion charts should only be used for reference only etc...

1/2019
http://mytabletennis.net/forum/foru...=1052830&title=rubber-hardness-scales#1052830
3/2018
http://mytabletennis.net/forum/foru...le=how-do-you-measure-sponge-hardness#1019830
8-9/2017
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993212
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993228
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993293
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993319
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993761
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#994182

Since then, I've been keeping an eye out for more info.

Asker E is Shore A0 or Shore E, after reading the respective standards. I referred to it as Asker E because I wasn't sure if they were the same.
Shore C and Shore W in China are highly likely Asker C.

DHS use Shore A for their in-house rubbers, and Asker C (referred to as Shore C) for ESN rubbers. See 2nd link from 2017 above. DHS have stated they use Shore A in articles of Table Tennis World about the making of Hurricane years ago.
Butterfly highly likely use Asker E. However, in a recent promo, a tech is seen measuring with the Asker C durometer attached to the CL-150.
ESN highly likely use Asker C and all brands that source from them.
Mizuno highly likely use Asker C. There is a TV program on Q5 in which the techs were measuring with the Asker C durometer attached to the CL-150.
Nittaku highly likely use Asker C, but the numbers shown on the official website and catalog are -10 degrees.
Yasaka highly likely use Asker C because in an article from volume 2/2004 of Table Tennis World there is a picture of Asker C durometer that Yasaka has given to the Japanese distributor(s) as a gift.

 

[Trevize84]

For the curious minds on the different hardness scales and why conversion charts should only be used for reference only etc...

1/2019
http://mytabletennis.net/forum/foru...=1052830&title=rubber-hardness-scales#1052830
3/2018
http://mytabletennis.net/forum/foru...le=how-do-you-measure-sponge-hardness#1019830
8-9/2017
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993212
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993228
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993293
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993319
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993761
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#994182

Since then, I've been keeping an eye out for more info.

Asker E is Shore A0 or Shore E, after reading the respective standards. I referred to it as Asker E because I wasn't sure if they were the same.
Shore C and Shore W in China are highly likely Asker C.

DHS use Shore A for their in-house rubbers, and Asker C (referred to as Shore C) for ESN rubbers. See 2nd link from 2017 above. DHS have stated they use Shore A in articles of Table Tennis World about the making of Hurricane years ago.
Butterfly highly likely use Asker E. However, in a recent promo, a tech is seen measuring with the Asker C durometer attached to the CL-150.
ESN highly likely use Asker C and all brands that source from them.
Mizuno highly likely use Asker C. There is a TV program on Q5 in which the techs were measuring with the Asker C durometer attached to the CL-150.
Nittaku highly likely use Asker C, but the numbers shown on the official website and catalog are -10 degrees.
Yasaka highly likely use Asker C because in an article from volume 2/2004 of Table Tennis World there is a picture of Asker C durometer that Yasaka has given to the Japanese distributor(s) as a gift.

Nice overview. Thanks. It's pretty ridiculous that manifacturer do not clearly advertise what they sell. Same for blades, you don't know the type of wood layers. I'm now in the mindset I do not buy anymore blades whose producer do not state publicly the type of each wood layer. People have right to know the crap they're buying.

 

[igorponger]

Asker was a standard scale with BUTTERFLY till 1985. They switched then to Shore A. Only two metering scales are used by rubber mnfcs, Asian ShoreA, Europian Shore О. Nothing else.

 

[7sagittarius7]

DHS use Shore A for their in-house rubbers, and Asker C (referred to as Shore C) for ESN rubbers. See 2nd link from 2017 above. DHS have stated they use Shore A in articles of Table Tennis World about the making of Hurricane years ago.
Butterfly highly likely use Asker E. However, in a recent promo, a tech is seen measuring with the Asker C durometer attached to the CL-150.
ESN highly likely use Asker C and all brands that source from them.

this seems the most likely to me, and after all, that's exactly what I said in the video

 

[TensorBackhand]

I will repeat the measurement on a different rubber, maybe something was wrong with this one. I am waiting for the personal rubber from Chen Meng to arrive, also 40d. And some more Loki and Victas rubbers, so I will measure them as well. I will let you know how much I measure on the Chen Meng rubber before any gluing or booster.

I don't know how accurate this image is. But if it is accurate, the 40d should measure 53d on ESN hardness. Look forward to your Chen Meng rubber.

Which Loki rubbers do you have?

 

[DukeGaGa]

For the curious minds on the different hardness scales and why conversion charts should only be used for reference only etc...

1/2019
http://mytabletennis.net/forum/foru...=1052830&title=rubber-hardness-scales#1052830
3/2018
http://mytabletennis.net/forum/foru...le=how-do-you-measure-sponge-hardness#1019830
8-9/2017
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993212
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993228
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993293
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993319
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#993761
http://mytabletennis.net/forum/foru...ew-nittaku-hurricane-pro3-turbo-orange#994182

Since then, I've been keeping an eye out for more info.

Asker E is Shore A0 or Shore E, after reading the respective standards. I referred to it as Asker E because I wasn't sure if they were the same.
Shore C and Shore W in China are highly likely Asker C.

DHS use Shore A for their in-house rubbers, and Asker C (referred to as Shore C) for ESN rubbers. See 2nd link from 2017 above. DHS have stated they use Shore A in articles of Table Tennis World about the making of Hurricane years ago.
Butterfly highly likely use Asker E. However, in a recent promo, a tech is seen measuring with the Asker C durometer attached to the CL-150.
ESN highly likely use Asker C and all brands that source from them.
Mizuno highly likely use Asker C. There is a TV program on Q5 in which the techs were measuring with the Asker C durometer attached to the CL-150.
Nittaku highly likely use Asker C, but the numbers shown on the official website and catalog are -10 degrees.
Yasaka highly likely use Asker C because in an article from volume 2/2004 of Table Tennis World there is a picture of Asker C durometer that Yasaka has given to the Japanese distributor(s) as a gift.

Um I'd say highly unlikely it's Asker C...

 

[zeio]

Check out the links, namely the one from 2019. Conversion charts are for reference only. They "are not direct conversions of physical property relationships". The quote below is for metal hardness, but the general principle applies to rubber hardness.

https://thermalprocessing.com/hardness-scale-conversion/

Numerical hardness values are unique to each hardness scale and method. For an indentation hardness method, the reported hardness numbers are based on the load on the indenter, the geometry of the indenter tip, and the measurements of the permanent plastically deformed impression in the sample. Hardness numbers may be calculated as a function of either a projected area or as the contact surface area of the indentation depending on the scale used. Conversion of hardness numbers from one scale to another is generally accomplished by reviewing the tables and equations available in externally published standards, such as ASTM E140 or ISO 18265 [1,3]. However, the guidance in the ASTM E140 standard regarding conversion from one scale to another, states the following:

“Conversion of hardness values should be used only when it is impossible to test the material under the conditions specified, and when conversion is made it should be done with discretion and under controlled conditions.” [1].

Furthermore, ASTM E384 confirms that there is no generally accepted method for precise conversion to other hardness scales [7]. While the conversion from one scale to another is straightforward, the converted hardness values need to be considered in the context of expected results from the thermal treatment process. The hardness conversion tables and equations in the standards generally correlate empirically derived numerical scales for specific materials and are not direct conversions of physical property relationships.

 

[DukeGaGa]

Check out the links, namely the one from 2019. Conversion charts are for reference only. They "are not direct conversions of physical property relationships". The quote below is for metal hardness, but the general principle applies to rubber hardness.

https://thermalprocessing.com/hardness-scale-conversion/

Yeah, I know it doesn't really convert. But It should still be in the ballpark, as we're not comparing hardness of different materials, we're comparing the same materials but measured with different scale. Otherwise, how could we ever compare the hardness of anything? The scale for shore A and asker C shows that 40 on shore A is somewhere in the range of 65 on asker C, that's a roughly 20% difference compared to the general consensus of it being around 55 of whatever scale ESN is. Which is why I highly doubt ESN is using asker C as their scale. Or it could be the other way around, ESN is using asker C, but DHS isn't using shore A.

Also I need to point out that using a durometer to measure a combined hardness of rubber and sponge isn't a good representation of what the hardness says on the package. For example, I bought a shore A durometer a while back and tested it on two sheets of Victas TD, I measured 10 spots on the rubber (four corners, four sides, two in the middle) and averages to around 37. On the package however it is marked as 57.5.

Anyway, I believe that people shouldn't be too focused on what the actual hardness of a rubber is. As long as it works for you why bother? And comparing hardness among different brands, or even among different models of the same brand doesn't really get you anywhere.

 

[TensorBackhand]

Well I went ahead and ordered a Shore O durometer from Aliexpress for $15.

It was driving me crazy not knowing the real hardness of each rubber.

Any rubbers you want me to measure and confirm for you all?

 

[latej]

Well I went ahead and ordered a Shore O durometer from Aliexpress for $15.

It was driving me crazy not knowing the real hardness of each rubber.

Any rubbers you want me to measure and confirm for you all?

All this time I was thinking I need to buy you one, to fulfill my dream of contributing massively positively to TTD!!!

 

[TensorBackhand]

All this time I was thinking I need to buy you one, to fulfill my dream of contributing massively positively to TTD!!!

haha, well I ordered the cheapest one I could find, so not sure how well it works.

Feel free to send a more accurate one

 

[latej]

haha, well I ordered the cheapest one I could find, so not sure how well it works.

Feel free to send a more accurate one

I got this one, for the similar price.

In the context of the discussion - since each of us may tend to measure slightly differently, but each of us measures his own rubbers consistently, it is useful to get measurements from 1 person, about multiple rubbers. Because then you can relate them. And if you know 1 of them (either you play or measure yourself), you can estimate the others. And then obviously, someone like you, is much more useful than someone like me, who plays the rubber until it dies and then takes another one, and everything is super slow. Note that the ej in my nick is not deserved, and doesn't mean ej ;-)

EDIT: So, I want them ALL!
Speaking about rubbers.

 

[TensorBackhand]

I got this one, for the similar price.

In the context of the discussion - since each of us may tend to measure slightly differently, but each of us measures his own rubbers consistently, it is useful to get measurements from 1 person, about multiple rubbers. Because then you can relate them. And if you know 1 of them (either you play or measure yourself), you can estimate the others. And then obviously, someone like you, is much more useful than someone like me, who plays the rubber until it dies and then takes another one, and everything is super slow. Note that the ej in my nick is not deserved, and doesn't mean ej ;-)

EDIT: So, I want them ALL!
Speaking about rubbers.

So how many rubbers have you measured so far and what have you found?

 

[latej]

So how many rubbers have you measured so far and what have you found?

Weeelll, I have here on my table about 28 edges, cut from rubbers, some of them duplicated, and ehh, some of them I am not really sure anymore what rubber that is. Ich muss Ordnung bringen! Verdammte S...!

I should have made an excel long time ago. Michael, make an excel, write the name on the sponge!!!

But what I have found? Hmm, I found I like hard dense chinese on the FH and 47 ESN on BH put simply. Measuring, apart from being able to post it, is a means of checking my sanity and feeling.

 

[7sagittarius7]

Which Loki rubbers do you have?

I'm waiting for the LAC to arrive

 

[turbozed]

I mentioned in the video that the H3 was previously tuned, and that the D09c still has glue residue. The G09c was glued once with 2 layers of glue, and before measuring I removed the remaining glue. H3 is the Provincial version that was glued 2 times to the blade with 3 layers of glue and 2 layers of booster. Before the measurement, it sat in a drawer for 5 months, so the parts of the booster evaporated. The other 3 rubbers were new, taken out of the packaging.

The problem with this kind of manual measurement is that it depends on the pressure of the thumb on the top of the device. So, because of this, it is possible to get a variation of even up to 3-4 degrees. I tried to apply the same pressure with my thumb on all 6 rubbers, but the resistance provided by the soft tensor sponge and the hard DHS sponge are completely different, so it is possible that there are errors in the measurement.

I have the same durometer as you. Along with the durometer were instructions on how to use it. You're supposed to use both hands with the index fingers cradling the bottom and two thumbs on the top part.

I also found that I can get the durometer to read 60+ degrees if I just press down fast as hard as I can.

However, with the above two handed technique and constant slow pressure, the readings become very consistent. By this I mean I will measure one rubber 6 or 7 times and it'll be within one degree of each reading. Then I'll do the same with a different rubber and have the same consistency. This is true if the rubber measured is 45d sponge or 51d. Also, I measure from both sponge side and topsheet side.

You maybe want to redo your video with a different technique.

 

[turbozed]

Weeelll, I have here on my table about 28 edges, cut from rubbers, some of them duplicated, and ehh, some of them I am not really sure anymore what rubber that is. Ich muss Ordnung bringen! Verdammte S...!

I should have made an excel long time ago. Michael, make an excel, write the name on the sponge!!!

But what I have found? Hmm, I found I like hard dense chinese on the FH and 47 ESN on BH put simply. Measuring, apart from being able to post it, is a means of checking my sanity and feeling.

I've found that measuring rubber cuttings gives you inconsistent readings compared to the whole sheet. When measuring entire rubber readings are consistent within 1 degree or so. With cuttings it can be 3-4+ difference. I wouldn't rely on cuttings.

 

[hclnnkhg]

I've found that measuring rubber cuttings gives you inconsistent readings compared to the whole sheet. When measuring entire rubber readings are consistent within 1 degree or so. With cuttings it can be 3-4+ difference. I wouldn't rely on cuttings.

I think the sample needs to be big enough to avoid any impact from the rubber/sponge edges. Unfortunately that means we can't measure the sponge-only hardness without ruining the rubber.

 

[turbozed]

I think the sample needs to be big enough to avoid any impact from the rubber/sponge edges. Unfortunately that means we can't measure the sponge-only hardness without ruining the rubber.

You're correct. I took the biggest pieces of sponge and used hot water to separate it from the top sheet. I tried measuring it and the measurements were wildly inconsistent and nonsensical. The sponge cuttings are too small and thin for measurement with this handheld device.