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Post by cricketdudeguy on Oct 7, 2012 3:03:18 GMT -5
hi dave yeah i am an aussie good quess sorry about what happened to ur son thats a real shame.to keep fit u can just do the the basic like 50 situps and push ups a night u look a pretty fit guy but core strength is the most important thing in cricket.sorry to her about ur son that a real shame hope he gets better a best of wishes for ur familys cricket. ps. exercise bikes are great.
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Post by Someblokecalledave on Oct 7, 2012 6:38:35 GMT -5
Cheers mate, he's coming along fine, hopefully by April, which'll be a year he'll be back playing cricket and hopefully only have scars to show for it. Graeme, I've posted your description of drift on my main blog mpafirsteleven.blogspot.co.uk/as you've highlighted something I've not considered before, but have seen mentioned, but kind of skirted around and that's the dynamics of the fact that the ball drops. At the moment I haven't got time to look at it in depth and consider it, but I reckon it's very useful. It's down to my learning style, I need to spend time thinking and trying to visualise it!
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Post by graeme on Oct 7, 2012 7:48:42 GMT -5
No worries Dave.
I was thinking more on the reason why Sean appears to get less drift with a cleanly spinning seam. I think it must be that the prominent seam must be counteracting the drift direction in the same manner that a seam bowler gets outswing with an upright seam pointed outwards. It's the only thing I can think of that would be affecting it. I think if the ball weren't spinning so much, I'd actually be seeing outswing on his deliveries with the seam pointed to gully.
Maybe with different or older balls, we'll see different behaviour.
Cheers, Graeme
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Post by Someblokecalledave on Oct 7, 2012 9:40:19 GMT -5
In Bob Woolmers book released just after he died there's an attempt to look at Warne's ball of the century and analyse it and in there, they conclude that one of the key aspects of the delivery is that it the seam is 90 degrees to it's flight direction, but I think elsewhere people say that if the ball is perfectly presented, this negates the Physics involved, it may even allude to it in the Woolmer explanation too, because as I recall they say in that explanantion that the axis of the spinning is tilted forwards not in a horizontal line. Does the axis during the drop therefore go from a slightly angled down direction to one that is ever more heading towards becoming more acute (Towards a vertical axis eventually if given time and space to continue travelling)?
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Post by graeme on Oct 7, 2012 22:23:36 GMT -5
The physics say the orientation of axis of rotation will remain very nearly constant because the ball is, in effect, a gyroscope*. If it starts out horizontal and pointing towards fine leg, that's where it will be just before the ball hits the turf. What do they mean by "perfectly presented" and "negating the physics"? The physics of that particular delivery are fundamental to what it did in the air and off the pitch. (Indeed, it's the same for all deliveries - it was just on display more for that one ...) Cheers, Graeme * There will be an extremely small variation due to precession, but in the time allowed for a delivery to complete, it will be absolutely negligable. The action of the air flow across the ball's surface/seam will also slightly modify the orientation of the axis through torque, but that's also going to be inconsequential in the time allowed. No point getting too far into the physics though - it will muddle and confuse. I think we should spend as much time contemplating the effects of changing rotation speeds on the orientation of the axis of rotation and precession as it actually takes the ball to land after release. That is, not very long at all ...
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Post by Someblokecalledave on Oct 9, 2012 12:56:02 GMT -5
Yeah - this is where we get bogged down in rubbish terminology on my part and the whole thing gets muddled! I need to sit down with someone who knows physics and piece of paper, so that it can be done with illustrations! I spoke to a woman at work who teaches physics and she nearly cracked it for me in a very short discussion, maybe I could go back to her and do the illustration thing with her? Chances are it may all fall into place!
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Post by shivam on Oct 11, 2012 2:57:46 GMT -5
yesterday i got better with drift. i was getting so much drift i couldnt imagine.well Someblokecalleddave,like when we bowl the top spin the direction of revs is towards the line its going. you can say the revs is attacking the air that is coming,because the ball is going forward.and the back spinner i also attacking the ball.but side spin is not attacking the ball.round the loop means, turning the ball horizontally makes it to spin different ways.round the loop in vertical.
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Post by shivam on Oct 11, 2012 3:12:01 GMT -5
if you think that total horizontal seam drifts the most.then try this-keep the ball in the hands and think that you are about to bowl a top spin.keep the arm up straight from where you deliver.bring your hand down till 9 o clock. now the seam is horizontal.bowl horizontal topspin.it wont drift.i dont why .l
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Post by leftie600 on Oct 16, 2012 18:45:00 GMT -5
From what discussed in the other forum:
1. If you deliver a ball spinning ball with the seam perpendicular to the wicket it will drift when the ball starts to drop in the air 2. If you bowl a ball like a UFO with the seam parallel to the wicket then it will start to drift straight away
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Post by shivam on Dec 3, 2012 22:43:29 GMT -5
side spin while drop it will drift
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Post by Someblokecalledave on Dec 6, 2012 19:58:10 GMT -5
From what discussed in the other forum: 1. If you deliver a ball spinning ball with the seam perpendicular to the wicket it will drift when the ball starts to drop in the air 2. If you bowl a ball like a UFO with the seam parallel to the wicket then it will start to drift straight away Leftie, you've done it again mate, that sounds again like something that is about to make sense to my non maths/physics brain, too late at the minute it's 1 am and I'm off to bed, but elements of that sound like there's some resonance with the video's made by the old bloke at Sydney Uni here... www.youtube.com/watch?v=t-3jnOIJg4k&list=FLtkyk-NkFTxMDscqPwDEPkg&index=55
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Post by cricketdudeguy on Jan 27, 2013 21:35:31 GMT -5
very interresting sometimes i can get my topspinner to in swing more like an offies arm ball
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Post by leftie600 on Jan 28, 2013 3:04:34 GMT -5
I've been thinking on drift a little lately. I don't bowl (in ANY format!!!) but I have been able to coach my son a little. He bowls his leggies to me and we experiment with the options he has before him. Sean's natural (stock) spin is one with the axis of rotation towards backward square leg, so that if the seem is upright, it points towards gully (a "45 degree seem"). This delivery will indeed drift, especially into a headwind or with a wind on Sean's left shoulder during run up. However, with a scrambled seem on the same axis of rotation, he gets more drift. I put this down to a tendency for a 45 degree seem to counteract drift in the same way a seem-bowler's angled seem produces an outswinger when he points it toward slips during the delivery. Any thoughts? Cheers, Graeme What you're saying is true in that you can bowl a legspinner with the seam at an angle where the ball swings (not drifts) out. I would like to see a video of a scrambled seam drifting in though as I get a feeling it's not quite what we all think. Is he deliberately bowling the ball cross seam or is the ball scrambled by accident?
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Post by leftie600 on Jan 28, 2013 3:06:05 GMT -5
very interresting sometimes i can get my topspinner to in swing more like an offies arm ball Same thing I quoted to Graeme, it's possible with the seam in the correct position to get a top spinner to swing out or in (not to be confused with drift).
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Post by Someblokecalledave on Jan 26, 2019 8:20:29 GMT -5
I'm checking in again to see if there's any interest in the forum. If you do come across the forum and realise there's not a lot going on don't despair check out my blogs as they are still very much active and in use and you can contact me and engage in discussion via the blog comments section at the bottom of each post. The blogs that are active that I'm contributing to regularly are... bowlingplans.blogspot.com/theoldwristspinner.blogspot.com/wristspinbowling.blogspot.com/
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