Posted by: tom.guerry (tom.guerry@kp.org) on Fri Oct 26 08:17:43 2001

> > > > > > Tom,please tell me about what you meanby the bat coming out of the arc,when and what causes it.This could be the holy grail of the subject.
> > > >>Tom,where is the head of the bat when you say it begins coming out of the arc,also is"nt this slowing it down ,or is it here that the torque takes over strong,which feels like the hands are being thrown or popped or whatever.Also does'nt this straightening of the bat make adjustments for hitting the ball square instead of pulling off it to much,like letting it stay in line with the ball a little longer,where a linear hitter may stay in line alot longer and slower.Seems Tim spoke of this with his son sometime back and when they came out of the arc late ,right before contact they started getting more solid contact more often.
> >
> > RQL-
> >
> > Let me answer by analyzing a clip.One nice demonstration is Nomar since he has such a "simple" swing.There is a thread at setpro with a side by side of Nomar hitting an outside(left clip) and inside(right clip)pitch.Each clip is eleven frames.Let's just concentrate on the right clip where he is turning on an inside pitch:
> >
> > http://www.setpro.com/ubb/Forum1/HTML/000394.html
> >
> > Let's look at the clip from the perspective of how the body moves to create the kinetic chain and good transfer mechanics.
> >
> > Front toe touch has happened by frame 3.This is a time when Nomar was taking a very small stride,more of a slight pick up/put down the front foot.
> >
> > The front heel has dropped by frame 5.Theoretically,the torso should start the hand path accelerating forward a few milleseconds after heel drop.So let's say "launch has happened by frame 5.
> >
> > Contact is just happening at frame 8.
> >
> > The sequence you want is maximum hip turn velocity when you hook up and start the torso turning,then hip deceleration to transfer lower body momentum to torso,then bathead swinging out away from axis of rotation to trigger energy transfer into bat,converted as much as possible into batspeed/angular velocity of bat.
> >
> > Frame 6 is approximately maximum hip turn velocity associated with the front heel dropping and the back foot turning over.
> >
> > By frame 7,the back toe has started to drag meaning that hip turn has slowed and momentum is being transferred to the torso.The bat head needs to come out after this has started,so it should start to come out of the arc of the hand path about frame 7 after toe drag has started.
> >
> > As long as the hands stay in and the bat is being fired to extension,the back toe will continue to drag.The hand path will slow as the energy is transformed as much as possible into batspeed,not dragging the bat.The slower the hands are going in the hand path,the more the energy is instead harnessed into turning the bat/creating batspeed/angular velocity.
> >
> > When the hands do cast away from the axis of rotation,another rective wave of torque goes down the back leg turning the foot back as the hips also drop back.This can be seen in the lastcouple of frames(10+11).This accentuates the "up" of the hips before this.It happens well after contact for the inside pitch,but at or before contact on the outside pitch(another topic).
> >
> > If launch to contact occurs over about 4 frames,the bathead comes out about halfway from launch to contact.
> >
> > As the bathead fires,it rapidly pulls the hands along with it and may make it difficult to "pull off the ball".You want the bat to turn,not be dragged by the hands.
> >
> > Can you see things this way in the clip?
> Tom,unfortunately I cannot pull up that page on my computer in fact when I go to look back at setpro pictures Many are blank with a red X in them.One ques.with your thread though how does the slower the hands go in the handpath the more the energy is turned into batspeed.

RQL-

It would really help to check out the clip.It works fine for me.Maybe your software is getting cranky.You might want to try it on another computer.If you are looking at the clip on a PC/windows machine,you can usually use the right mouse click to do stop action.

The underlying physics idea is to generate and transfer as much momentum as possible and convert the torso momentum as much as possible into batspeed(angular velocity of bat).The more efficient your "transfer mechanics",the more the bat turns around a point between the hands,rather than having the hand path continue forward driven by arm extension.This goes along with Jack's "oarlock" description of the hands.Pre swing and prelaunch,the top hand is turning the bat around a fairly fixed bottom hand.The arms are moving the wrists while maintaining/creating tight connection and NOT extending.Torso turn starts the hand path.As the bathead fires,the forward progress of the hand path slows as energy is preferentially funneled into turning the bat(not pushing the knob-push swing-associated with premature arm extension).This is "bottom hand torque" where the forward progress of the top hand slows as the bottom hand pulls the knob around the top hand oarlock on the inside pitch.The hands and wrists are turning with the bat,but the arc of the hand path is greatly decelerated.The hands move again when they cast away from the body after contact on the inside pitch,at or even before contact for the outside location.