In the golf equipment side of things, there are essentially two kinds of iron shafts, parallel and taper tip.
To my knowledge, when steel shafts were first made, they were made as taper tip shafts. Here’s a diagram showing the differences in parallel tip (.370, shown on top) and taper tip (.355, shown on bottom).
As you can see, the tip of the parallel shaft runs ‘parallel’ to each other. The taper tip ‘tapers’ down to 0.355 inches in diameter as it gets towards the tip section.
With taper tip, each shaft is a different length and it has a certain club it fits into. For instance, a PW shaft may be 37-inches long. The clubmaker then trims the shaft from the *butt* end of the shaft length. So a golfer who wants a 36 inch long PW, may have to get the *butt* end of the shaft trimmed 2 inches and then with the shaft installed it will come out to a 36 inch club.
The parallel tip has every shaft the same length and there is no one particular shaft for each club. If you’re installing parallel tip shafts in a set of irons, the raw/un-cut shafts may all be 41 inches long. You first trim from the tip end. The shaft company usually gives instructions as how much to trim from the tip end depending on the club.
For example, you may have to trim ½-inch from the tip end on a 3-iron and 2-inches from the tip end on a 7-iron. Once the tip end is trimmed on a parallel tip shaft, you then trim from the butt end to the length you want the club to be.
It’s reported that in the 70’s, more companies started to go to parallel tip shafts because it would save them money on inventory. No more having to worry if you have, say, enough 6-iron shafts for your 6-iron heads in stock. All you have to do with parallel tip is grab any shaft, trim to specs and you’re good to go.
However, parallel tip shafts started to develop a bad reputation. People often thought of them as ‘cheap’ because they saved the OEM’s money which people thought meant that they were lesser in value.
Last year I wound up purchasing some Wishon 555 irons and installed some parallel tip KBS Tour shafts in them. I don’t think I’ve ever played with parallel tip shafts before then, but I decided to install them because I was not familiar with installing taper tip shafts (.355) inside parallel tip (.370) hosels. However, I do currently install taper tip inside parallel tip hosels using a brass shim and it’s quite easy.
One of the biggest gripes against parallel tip is supposedly the feel of the shaft. However, I’ve never had a problem with the feel of a parallel tip shaft versus its counterpart in taper tip. I can see why there could be a difference in feel as if you look at Wishon’s Shaft Bend Profile software (www.wishongolf.com), you will see different shaft bend profiles of a parallel tip versus the same make and model with a taper tip. Usually, it’s not dramatically different. But, it can be different enough to alter the feel. So if you were fitted for a taper tip shaft and then tried that shaft in parallel tip, you could think that just because they are parallel tip that is causing the difference. But the reality is that the bend profile has changed because they simply have different bend profile characteristics.
However, what I’m starting to notice in some very early research is that the parallel tip may be overall better for golfers than parallel tip.
Because if I make a parallel tip and taper tip clubs the same MOI-weight, the static weight for the parallel tip has been lighter.
According to Wishon in his book ‘The Search For The Perfect Driver’, one of the biggest determining factors in being able to swing a certain club faster is static weight. If at rest, a driver that is the same length, loft, etc is lighter than the other driver, I’m likely to see some increased clubhead speed.
This makes sense…the club is truly lighter, so it’s easier to swing it faster. Of course, that does not always equate to hitting it longer or better, but as far as clubhead speed goes…lighter usually equates to faster.
So what I’m seeing with the parallel tip vs. taper tip is that I can take two shafts that weigh the same, but have different tip diameters. For example, a KBS Tour parallel and taper may both weight 130 grams.
I can then take both clubs and make everything the same, including the MOI-weight (we’ll say at 2,725). But, when I measure the static weight of the club, so far the parallel tip shafts have weighed lighter than the taper tip shafts.
For example, I did this recently with a couple of Wishon 555M 6-irons. I have a KBS Tour parallel tip shaft weighing in at 130 grams. Then I installed a Nippon 1150GH taper tip that weighs in at 125 grams. I then matched the MOI in at 2,725. Despite being the same make and model 6-iron, with the same grip, length, etc….the parallel tip KBS Tour 6-iron weighs about 8-grams *less* than the Nippon 1150GH taper tip 6-iron. And remember, the Nippon shaft actually weighs about 5-grams less than the KBS Tour, but when installed and MOI-matched, the static weight of the 6-iron with the KBS shaft is lighter.
The reasoning appears to lie within the taper tip having a ‘constant weight’ design. So when the parallel tip shaft is trimmed, it takes a lot of weight off the shaft. But since I match the MOI of the clubs, it still is taking the same amount of force to swing the club, I can just add some speed to it with the lighter static weight club.