DG S300 vs. Project X (6.0)

[cwdlaw223]

I know that the PX generally has lower spin, stiffer butt and higher launch than the DG.

How much less spin would the PX have than a DG with the same swing for a 6 iron? Does it drop by 200 rpms? 300rpms??

Curious. My fascination with my 5* driver is leading me down a path of less spin. Every day there's something new!!!

Next week will be the Axis 1 putter that I'm dying to try.

[cloran]

I wouldn't want less spin with my irons. The more backspin you have, the less side spin you have... the straighter the flight. So, if you can hit it pure you'll hold your lines better. Too much spin with the irons is a good problem to have. Here's Sean Foley saying that very thing:

[cwdlaw223]

Check out Rohlio's post today on my driver face thickness thread:

"Curvature is related to spin axis. Because the lower loft is spinning the ball less than the higher lofted driver it will not curve nearly as much.

Fast moving air over the ball creates lower pressure which allows the ball to have lift in that direction. When the ball is spinning on a tilted axis the ball will move in the direction of the lower pressure at the top of the spot perpendicular to the axis of rotation, thus causing it to slice or hook. The faster it is spinning, the lower the pressure will be and the more the ball will move in that direction.

So it makes sense that if you are putting less spin on the ball it will be less workable."

I think the backspin helps accentuate the effect of the axis tilt. How much of an accentuation? I don't know and I'm trying to piece together the puzzle. I suspect the PX has a couple hundred less RPMs than the DG and therefore, tighter dispersion.

Rohlio - I hope I didn't quote you put of context or it only related to a driver swing, but your excellent response today spawned this topic.

I also wouldn't be surprised if at some point so much backspin overrides severe axis tilt due to the significant lift and lack of distance caused by severe backspin (sort of like gear effect overriding everything).

[pavaveda]

There is only one spin. There isn't backspin and sidespin. There's spin axis (degrees) and spin rate (rpm).

[cwdlaw223]

How is the ball spinning around the spin axis? The ball can only spin forward or backward on a single axis.

Revolutions per minute going where on the ball in relation to the target?

There's only backspin and axis tilt (no sidespin), but the ball is spinning backwards; hence the term backspin. Trackman can try to call in spin rate, but the ball is spinning backwards to assist with lift.

[rohlio]

Mar 23, 2011 20:24:39 GMT -5 pavaveda said:

There is only one spin. There isn't backspin and sidespin. There's spin axis (degrees) and spin rate (rpm).

This is correct.

Backspin does not cancel sidespin or anything like that. T

The ball is spinning in the opposite direction of flight. This action creates variable pressure around the ball, that is oriented in relation to the spin axis, such that like an airplane wing there is low pressure above the ball and high pressure beneath it. If the ball is struck in such a fashion that the ball is spinning about a tilted axis this will cause the ball to curve in the air, that is how you produce a fade or a draw.

I wish I was a 3d artist so I could draw this for you. Try to think about it this way. An airplane banks left because you tilt the horizontal axis of the wings such that the lift force is no longer in direct opposition to gravity it now has a horizontal component to it's lift vector. The airplane will move towards the new direction of low pressure which is whatever direction it is banked towards.

A golf ball moves the same way ( in large part due it's dimples) Such that when you hit a draw a line drawn through the horizontal equator of the ball would be tilted such that the left side of the line ( as viewed dtl) would be lower than the right side. The ball is spinning perpendicular to this line in the air.

Searching for low spin has a two fold effect however. While it certainly makes the ball curve less as it spins it also lessens its lift away from the force of gravity. Such that if you could make a ball which doesn't spin at all and thusly, doesn't curve at all, it would also fall to ground very fast relative to a ball that is spinning and dimpled.

There is a butter zone, many people would gain yardage by having MORE spin on their driver, unless the spin is excessive to the velocity of the struck ball, in which case it will balloon as it has too much lift.

With irons the goal is not simply to hit them as far as possible but also to have them rise high in the air and land softly and stop quickly. With too low of a spin rate none of those features will be available, and at very low spin rates you will start to hit them significantly shorter et al.

One of the reasons that low spin rate (relatively, there is still too low) is so desirable in a driver is that you get to tee the ball up and therefore can attack the ball with a positive attack angle bringing a less deflected strike on the ball and giving it a higher intitial launch velocity. Since you can't tee up an iron in the fairway and also because in order to make solid contact you must be hitting down on the ball, spin is very important in establishing a solid ball flight.

Also to your point I have found 6.0 to be much more shaft than the s300. I am of the opinion that if you are in the comfortable middle with s300's you would be probably better suited to 5.5's or 2x soft stepped 6.0. That however is purely personal experience.

Hope this helps.

Check out this page from trackman for a somewhat decent picture of the idea of spin axis

www.mytrackman.com/TrackMan.Online.DrivingRange/Data.html

[cwdlaw223]

pavadea indicated there's no such thing as backspin. Do you agree Rohlio? If so, which way is the ball spinning?

Backwards in relation to the target and often tilted. Thus, backspin does exist. If the exist were tilted so far it might look like side spin, but that would be an exception, not the rule.

[rohlio]

Mar 23, 2011 21:45:28 GMT -5 cwdlaw223 said:

pavadea indicated there's no such thing as backspin. Do you agree Rohlio? If so, which way is the ball spinning?

Backwards in relation to the target and often tilted. Thus, backspin does exist. If the exist were tilted so far it might look like side spin, but that would be an exception, not the rule.

You are reading him wrong. He is saying you cannot separate the two. The ball spins in one direction and with a particular tilt. This defines the spin axis of the ball. He meant there is no sidespin and backspin, which act separately from each other.

Of course it is spinning with, "backspin" as that is the term used to describe a ball which is rotating in the opposite direction of it's overall movement. However that backspin is not happening perpendicular to the horizon, it is tilted to some degree ( 0* is a possibility of course).

IMO; and only he could answer this, he was speaking to cloran's post in which he stated "The more backspin you have the less sidespin you have...", which is only the case if you view the spin axis as being composed of two components. I would think a more accurate statement would be " The less spin axis tilt you have the less the ball will curve.", since the spin axis is a single measurement
and not made up of two different pieces.

The ball spins backwards, but not straight backwards, it spins perpendicular to the tilted spin axis and the spin rate (rpm) at which it does so will define how much the ball curves when it is applied to the amount of tilt.

I believe that trackmans goal in eliminating the seperated measurements of sidespin and backspin; and providing the unified notion of spin axis, was to eliminate this notion that backspin cancels out sidespin. Because the ball is not a gyroscope with seperate components that can spin about different axes, that type of thinking is simply wrong headed.

In short: a ball spins backwards about it's spin axis and the tilt of this axis will define the curvature of the ball.

[cloran]

I didn't mean my post to read "The golf ball is capable of spinning in two different directions at the same time." That seems to be how it was taken.

[pavaveda]

Yes, I was responding to cloran's post. I was typing on my phone, so sorry I didn't expound on what I wrote. I probably could've written it more clearly.

My main point was that I often see posts talking about backspin and sidespin as if they can exist at the same time, and wanted to clear that up. Fortunately, rohlio has done that for me! (And cloran, I figured you probably didn't mean it that way, but if I read it that way, maybe others did as well. Hence, my post.)

FWIW, I hit several "drives" recently that had topspin! Of course, I hear that several of the pros are doing this now, so I feel pretty cool right now.