2 vs. 4 seam FB

[scorekeeper]

Assuming other than across the seams as opposed to with the seams, a pitcher uses the same grip, arm slot, etc., what, if any, are the reasons a 2 seam FB doesn’t have the velocity of a 4 seam FB.

[Roothog66]

With the two seam, more stitching is exposed to the atmosphere which provides more resistence.

[Roothog66]

I think, also, that the fact that the seams become more unbalanced cause a drag on it as well.

[scorekeeper]

Well Happy New Year Root!

Not being a physicist or anything approaching it, I won’t argue what you said. However I will ask if you can explain both statements a bit better so that I can use that explanation to show someone what you mean by using a baseball.

Not saying this is the all-encompassing word on it, this link http://www.thecompletepitcher.com/pitching_grips.htm seems to say the real difference is in how loose or tight the grip is as opposed to how the seams are aligned. Of course that makes me wonder what would happen if the 4 seamer were gripped more tightly and the 2 less tightly.

I’m not trying to be a contrarian here, but rather trying to understand what’s causing the end result. I’m more than willing to accept that different grip pressures make the ball do different things, but to be honest, I don’t see that more seams are exposed to friction one way otr the other.

[Chris O'Leary]

With the two seam, more stitching is exposed to the atmosphere which provides more resistence.

Paradoxically, the more stitching that is exposed, the LESS the resistance, which is why a 4-seamer is faster.

It has to do with the boundary layer.

[Chris O'Leary]

Well Happy New Year Root!

Not being a physicist or anything approaching it, I won’t argue what you said. However I will ask if you can explain both statements a bit better so that I can use that explanation to show someone what you mean by using a baseball.

Not saying this is the all-encompassing word on it, this link http://www.thecompletepitcher.com/pitching_grips.htm seems to say the real difference is in how loose or tight the grip is as opposed to how the seams are aligned. Of course that makes me wonder what would happen if the 4 seamer were gripped more tightly and the 2 less tightly.

I’m not trying to be a contrarian here, but rather trying to understand what’s causing the end result. I’m more than willing to accept that different grip pressures make the ball do different things, but to be honest, I don’t see that more seams are exposed to friction one way otr the other.

Some of it is that 4-seamers are thrown flatter, which creates a more uniform, flat spin.

2-seamers are thrown with more pronation, which creates a multi-axis spin. 2-seamers are also thrown slightly off-center, which reduces the force that is transferred to the ball. Backspin gets converted into some side spin.

[Roothog66]

It's certainly true that a difference in grips is often a component of a good two-seamer. When a 4-seam fb is thrown, the four cross seams intersect with the atmosphere in an even manner which allows the flight of the ball to cut against the air in a way as to minimize the effects of gravity which is why the 4-seam was commonly known as a rising fastball. While it doesn't actually "rise," it doesn't fall as far as a 2-seamer. With a four seamer, many of the stitches are thus on the sides of the ball and not in direct contact with the air stream that pushes against exposed stitching. When a two-seamer is thrown, all the stitches are in conflict with the atmosphere. In addition, as the ball rotates, the cross stitches are not evenly distributed which allows for gravity to have a greater effect on the ball.

[Roothog66]

Paradoxically, the more stitching that is exposed, the LESS the resistance, which is why a 4-seamer is faster.

It has to do with the boundary layer.

My understanding has always been that with a 2-seamer, the stitches that come into contact with wind resisteance are not hidden on the side in the same manner as a 4-seam fb. Rotate a two seamer like it does goingt hrough the air and you will see that every single stitch is in the path of wind resistance. I'll have to think about the idea that the 2-seamer is pronated to a greater extent.

[Roothog66]

Admittedly, most baseball people seem to agree that a 4-seamer provides more resistence, but it doesn't make sense to me. It would seem (pun intended) that with a two-seamer, the long seams provide unbroken wind resistance which would reduce the rate of rotation on the ball. Just playing around with the ball now, though, and trying to see if I think there is more pronation on a 2-seamer. It does sort of appear that in order to get spin on the ball I pull a little harder with the middle finger than with a 4-seamer.

[Francoeurstein]

Here's my personal standpoint, using no physics or outside knowledge whatsoever (mostly bc I don't have any )

But, a 2-seam is held more loosely in my fingers, and I (not sure about others) turn it over slightly. The 4-seam is held with a more firm grip and thrown straight as an arrow. That's just based on how I pitch.

[scorekeeper]

LOL. It seems no one can be either completely right or wrong.

All this talk seems to me to show that about the best anyone can do is to make very general statements about either pitch, and then let each individual experiment for him/herself to get out of each pitch what works best for them.

I’ve read so many times that a pitcher doesn’t have a 2 seamer in the arsenal, but I’ve honestly never really understood why not. The reason for that thinking is to me, if its only a matter of changing the grip so that the seams interact with the air at a different orientation, every pitcher should only have to rotate the ball a bit in order to throw a 2 as opposed to 4 seamer. But the reality seems to be that there’s something else going on that’s difficult to put into words that can be easily understood, otherwise every pitcher could and would have an effective 2 seamer.

Putting one’s finger on what that “something else” is, is difficult enough, but then understanding that for each pitcher its gonna be slightly different explains why every pitcher can’t seem to do it, or why for some it seems to be very simple while for others its an obstacle that’s very difficult to overcome.

I’m sure this will be something most of you have heard before. We had a kid who only threw a 4 seamer, but was very successful. When you watched closely you would see that his FB “tailed” to his pitching hand side, and being a LHP, that worked very much in his favor against RH hitters when thrown “away” from them. My son was a low slot RHP who very seldom threw a 4 seamer and had great success against RH hitters by keeping the FB “in” on them.

What I’m saying is, there are all kinds of way to have success with a FB if it moves horizontally, even a little bit, as long as it can be controlled. But that success is much harder to come by unless the velocity is much higher. Both my son and this other boy weren’t exceptionally hard throwers. In HS my son could hit 87-88 easily enough and this other boy 86-87, but neither were what anyone would call hard throwers. My son lived off the movement on his “2” while the other boy feasted off the movement of his “4”, but they both had outstanding control of not only their FB but their other pitches as well.

I’d really like to be able to explain to youngsters what makes up the difference between the two pitches, but from what’s been said so for here, a pitcher can pronate a bit more when throwing his 4 and get a different action from it that might be better for him than changing the seam orientation, or if he’s getting too much movement on the 2, do the same thing but with a 4 seam orientation.

Maybe it would be better if the pitch wasn’t called a “2 seam FB”, but rather only a “cutter” or “sinker”.

[skipper5]

If the orientation of the seams have anything to do with the increased velocity (as opposed to grip and fingers, etc.), then in my humble uneducated opinion the increase owes to the fact that four seams cutting the air with maximum backspin creates less of a "wake", which means there's less drag.

Also, it's possible that when a pitcher knows he's throwing a straight-arrow pitch--no movement to fool the batter-- he puts some extra armspeed into it, whether its conscious or unconscious.

[Francoeurstein]

I throw about 75% two-seams and 25% four-seams. My 2 is about 79-81 with very nice tail, and my 4 is about 82-84 and completely flat. I wish I could tell you why, haha.

[skipper5]

Paradoxically, the more stitching that is exposed, the LESS the resistance, which is why a 4-seamer is faster.

It has to do with the boundary layer.

That's what I wanted to say.
I vote for this answer.

[songtitle]

efastball (ahem) says:

[4SFB] This is the fastest pitch because the ball has four seams cutting against the air.

the increase owes to the fact that four seams cutting the air with maximum backspin creates less of a "wake", which means there's less drag.

Agree