Hi Dave,
At 02:50 AM 1/24/2005 -0500, you wrote:
Very interesting, Alan. Thanks for posting that.
A couple of questions:
At 09:27 PM 1/23/05 -0800, Alan Brooks wrote:I turned a 3 to PW set into 260-g heads, tweaked the loft the same, and mounted them on the same shafts, same frequency, same grips, etc., and went to the range.
I assume you mean you tweaked the lie, not the loft.
What was your constant length? Since that is a 6-iron weight, or maybe a heavy 5, I am going to assume the constant length of all the clubs was between 37.5" and 38".
Yes, I meant the lie, thanks - it was late. Loft was standard for each head number. The length was right at 38 inches using TX90 shafts.
I got predicted distances from the short and mid-range clubs, but less than predicted from the longer (3 and 4 irons) clubs, but not by much (maybe 10-15 yards).
When you say "predicted", what was your method for prediction? Max's trajectory program? Wishon's? The predictions I posted a few weeks ago?
I used Max's program. I normally get predicted distances out of my long irons with greater variability than my short ones but I hit them well often enough to have a good idea what a good hit produces. I was hitting the two sets of clubs side by side on the range. Needless to say this meant my poor muscle memory was confused, but I hit enough good shots with both for, I think, a valid comparison. That doesn't mean that I wasn't subconsciously 'trying harder' with my low lofted irons and changing my swing mechanics, only that the impact felt 'clean'. The course I played on with them is hilly and 'breezy' so it was hard to know if distances are comparable, but they did seem to be shorter with the low lofted constant length clubs. Interestingly, my scores were about the same with the constant length clubs as what I normally shoot on this course.
I have to ask this -- sorry. Have you measured what you get from your normal-lengths 3i and 4i lately? My predictions were based on somebody who can hit the 3i and 4i as well as their shorter clubs; that's what the program assumes. But most people cannot. So I'm really asking if you get the same loss of distance from your normal-length 3i and 4i, compared with a computed ideal.
Directional control with the short clubs was not as good as with traditional clubs, but with the long (forgive me - low lofted) clubs it was better. I don't know how much of my directional control results were a consequence of the grinding/taping I did to the heads.
This should not be too surprising. Most people have better directional control with their shortest irons, and lose that control incrementally as the clubs get longer. A lot of that is probably due to loft, but probably not all of it. (If it were all of it, then there would be no merit at all for constant-length clubs.)
So, for the component of control due to length, you were only getting what you would get from a 6i or 5i -- for ALL the clubs. That would mean worse control for, say, your wedges and 9i and better control for your 4i. I suspect that, if you made all the clubs the length of the 9-iron (no grinding, but LOTS of lead and you might break some heads getting the lie right), you'll get great directional control but lose more distance.
Exactly. And that may be why My Ostrich Golf is going with the 7-iron equivalent head weight instead of my 6-iron equivalent. After getting a response from Tim Hewitt at MOG I loaded a 4-iron up to 270-g and got even less distance. Note that MOG is only going to a 4-iron equivalent.
Also, in order to try and keep the heads balanced toe to heel I was making my mods to the heads in the area behind the etched area on the club face. Lead was added low there for the low lofts and material ground away for the high lofts. This meant that my high lofted heads had a greater MOI about the vertical through the head c.g. than a set that had been designed for that weight and my low lofted heads had a lower MOI about that vertical. I did manage to keep the club head c.g. about where it was before mod. It was maybe slightly higher on the highest lofted clubs where I ground the most off the back of the heel.
Please keep us posted.
DaveT
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Regards,
Alan
