Two Seamers

[pobguy]

Dr. Nathan proposed a theory as to why the split fingered fastball moved.

Just to be clear: I am not saying *all* split-finger fastballs move the way the Garcia's did. In fact, it is quite the opposite. It was the unusual nature of that particular pitch that led to the study that Cross and I did. In fact, I scoured the PITCHf/x database to find other examples of the same movement. I found just a handful of others. For all the other split-finger fastballs, the movement was armside, not gloveside.

 

[pobguy]

This may be a stupid question, is there a difference in speed between a twelve-six spin 2-seam vs a 4-seam fastball?

I've read that a 4-seam baseball thrown with six-twelve (backspin) is more aerodynamic and thus a faster pitch.

That's an interesting question. I think the movement of the two pitches would be the same, assuming pure backspin in both cases. It *might* be the case that there is a little less drag on the 4S. If it were indeed true, then the 4S would be a bit faster (assuming the same release speed), since it would lose a little less speed due to drag. Laboratory data are a bit inconclusive about that, and in any case the effect cannot be very large.

 

[riseball]

That's an interesting question. I think the movement of the two pitches would be the same, assuming pure backspin in both cases. It *might* be the case that there is a little less drag on the 4S. If it were indeed true, then the 4S would be a bit faster (assuming the same release speed), since it would lose a little less speed due to drag. Laboratory data are a bit inconclusive about that, and in any case the effect cannot be very large.

All things equal putting more seams to the air results in less drag?

 

[pobguy]

All things equal putting more seams to the air results in less drag?

Yes, at least that is the theory. Adair talks about this in his classic, The Physics of Baseball (3rd ed, page 61). Lots of wisdom in that book.

 

[Greenmonsters]

Just noting that while JJS and Slugger are having a heated, knock-down, drag-out disagreement, they are also proving that such discussions/arguments can be conducted intelligently and rationally (relatively speaking of course). The Theological Hitting thread should take note. Well done boys - now patch up the cuts and come out swinging at the bell for the next round!

 

[javasource]

...just try to understand the concept then maybe you will see it differently...

Ok... here goes...

Is that North and South America... or an English guy on vacation in a speedo?

I may be way off-base...

 

[riseball]

That made my day JS.

 

[CLM265]

Chaos theory

 

[BuckeyeGuy]

Chaos theory

Lorenz doesn't apply here, as we have a well defined initial state and well understood, limited inputs.

JJ, correct me if I'm misstating things (like I even need to say that): the 2S pitch with a slight axial tilt on the Z axis, or yaw has movement determined more by Bernoulli than Magnus. The goal would be to maintain the steepest possible pressure gradient along the axis, high -> low with the low on the side you wish the ball to break towards.

 

[CLM265]

Think JJS and Slugger.