Print

[Six Sixes Cricket]

More or less. CoR provides the variation on the velocity caused by an inelastic impact, so effectively adds into the conservation of momentum equation as follows:

(m_a+m_b)v_a = m_au_a + m_bu_b + m_bC_r(u_a+u_b)

That's what I calculated.

[jonpinson]

Which element of the equation is the offset spine?

[norbs]

I should have put an exclamation after my last post instead of a question mark. Mass is taken into consideration in the CoR equation

Which element of the equation is the offset spine?

It is related to CoR based on the fundamental node of vibration I'm glad you asked....

[RossViper]

I did reply to this fully but it either got lost or pulled, either way dont see what COR has to do with the org question.

With out the detailed explination maths wise not much differance, practically slightly more mass is easier to get a higher exit V.

[pacman75cricket]

Good to see Norbs about for these questions

[norbs]

I did reply to this fully but it either got lost or pulled, either way dont see what COR has to do with the org question.

With out the detailed explination maths wise not much differance, practically slightly more mass is easier to get a higher exit V.

CoR is related to lots of things but ultimately it is about rebound so it directly related to the question volume or swing speed.... sometimes I wonder what people read I said the same thing about volume

So to reiterate CoR is related to momentum and therefore the velocities are related to mass in the answer....

Before you say I haven't got it right do some checking yourself

Finally if you look at Vectors as you state... what relationship does that have seeing as there will be shift of xxxxxxxxxx as you swing the bat?

[Johnny]

I think SAF should do a bat called 'The Alchemist', as they seem to use all this science to turn a piece of willow in to cricket bat gold

Seriously, I love the amount of thought that Norbs puts into how a cricket bat works, and can't wait to own my own SAF one day

[Canners]

i want this one










[/quote]

[RossViper]

CoR is related to lots of things but ultimately it is about rebound so it directly related to the question volume or swing speed.... sometimes I wonder what people read I said the same thing about volume

So to reiterate CoR is related to momentum and therefore the velocities are related to mass in the answer....

Before you say I haven't got it right do some checking yourself

Finally if you look at Vectors as you state... what relationship does that have seeing as there will be shift of xxxxxxxxxx as you swing the bat?

Sorry norbs, not saying you're wrong, I still dont understand or see how mass is related to CoR, I get that it's added to the momentum equations to account for inelastic collisions, like tim2000s said, but that then includes the masses of the objects.

Anyway, no worries, not the end of the world, i think we get to the same conclusion, I guess I'll keep looking into it!

[norbs]

Sorry norbs, not saying you're wrong, I still dont understand or see how mass is related to CoR, I get that it's added to the momentum equations to account for inelastic collisions, like tim2000s said, but that then includes the masses of the objects.

Anyway, no worries, not the end of the world, i think we get to the same conclusion, I guess I'll keep looking into it!

CoR is basically the speed of bat [at impact point] and ball after collision / the speed of bat [at impact] before the collision

Swing weight which determines the speed of the bat is based on the mass moment of inertia [therefore mass is part of the calculation]

CoR also takes into consideration, the energy losses

So for example....

When swinging a bat, the fastest point on the bat will be the toe. So you'd assume that would be the fastest exit speed. But as we know strong vibrations are generated for impacts near the toe plus it is generally thin and therefore makes it less effective.  This is transposed into CoR, bouncabilty or ping if you will

[Ryan]

i want this one

i'll second that! it looks massive for the weight

[jonpinson]

Andy all this detail you have calculated is fascinating to an analytical mind like mine, but real world, do you think it makes all that much difference? We see mass produced bats (made both here and Asia) which are most certainly not designed based on this theory and formulae yet still perform brilliantly. I don't doubt the validity of the research, nor the results and theories found therein, but have you found the real world improvement in performance to be such that genuine claims can be made?

I think those of us who are a bit world weary and sceptical about the latest claims made about the latest mass produced bats have come to the conclusion that actually, edge size, density, degree level physics research etc are far less important than having a bat that feels right when we pick it up. A bat that feels comfortable, a bat with no aspects with which we are unhappy. If that happens to be a bat with a modern shape, so be it. If it happens to be a bat steeped in tradition, so be it.

[norbs]

Andy all this detail you have calculated is fascinating to an analytical mind like mine, but real world, do you think it makes all that much difference? We see mass produced bats (made both here and Asia) which are most certainly not designed based on this theory and formulae yet still perform brilliantly. I don't doubt the validity of the research, nor the results and theories found therein, but have you found the real world improvement in performance to be such that genuine claims can be made?

I think those of us who are a bit world weary and sceptical about the latest claims made about the latest mass produced bats have come to the conclusion that actually, edge size, density, degree level physics research etc are far less important than having a bat that feels right when we pick it up. A bat that feels comfortable, a bat with no aspects with which we are unhappy. If that happens to be a bat with a modern shape, so be it. If it happens to be a bat steeped in tradition, so be it.

There are a number of things that help me. Understanding why bats perform and how, allows me to create shapes and have a good idea what makes them tick and what variations I can do with those shapes.  It also gave me a better insight into willow and therefore the pressing of that willow. I didn't want to get into this and not really understand what was going on with the bat and why, it makes me feel great deal more comfortable with what I do.

The differences I think are based on translating that theoretical knowledge into those performance areas. By genuine claims I assume you mean some type of lab testing against other bats.  In that case nope it hasn't been done, there has been no point do to this for 2 reasons. Since I've been doing this, I have never stated that any of the bats created are better by x% then anyone else's bat.  That isn't what I do or why I do it, I'm not in a bun fight here with anyone, I respect all the guys that make there own. Secondly, as stated before I'm comfortable with the bat shapes produced and that makes it a lot easier to do my own thing, that is, the theoretical and translating that to the practical [making me a bit of geek but I dont mind that]

Ok Mr World Weary   , we are all skeptical it is in our nature with all those "to good to be true" claims.  At the end of the day a lot this edge size, density, research is down to helping you make a decision based on what you like.  I am funnily enough in agreement with you, the bat you use has to be right for you. Is that bat comfortable, yes, do I like the look of it ,does it make me feel confident, yes, finally, test it for performance. Tick all of those and you'll be very happy. Those things are what I aim to achieve based on knowing how to balance and press a shape that has been designed from theoretical principles

I really hope that made sense

Norbs

[Canners]

Very good Norbs....

i'm going with Mass as the biggest sixes i have hit are with my, H4l moster bat which weighs in about 2.11 now, and my M&H Retro which was also about 2.11, both massive bats.....

but the hardest i have ever hit a ball was with my 2.9 Talisman, i could quite easily have killed the umpire if he wasnt so quick to duck out of the way..... The thing is the pressing on the pink Talisman is unreal and anyone who has seen it and tapped it up agrees..........

So now i just need to find a bat that is mahoosive for the weight, alows me to generate maximum swing speed and is pressed to perfection..... The search continues

[Number4]

More or less. CoR provides the variation on the velocity caused by an inelastic impact, so effectively adds into the conservation of momentum equation as follows:

(m_a+m_b)v_a = m_au_a + m_bu_b + m_bC_r(u_a+u_b) = Canners Dream Bat

Should be quite easy to make what with all the calculations and science