First Cut
Wilson's D9 Forged irons: what you need to know
WHAT YOU NEED TO KNOW: Wilson’s follow-up to its D7 Forged uses a revamped “power hole” design that it arrived at through artificial intelligence to reduce the amount of urethane used. Doing so not only creates more ball speed, particularly on heel strikes, but lowers the center of gravity for a higher launch angle and more desirable angle of descent.
AVAILABILITY/PRICE: Available April 4, the Price for a seven-piece set is $1,050 in steel and $1,150 in graphite.
THE DEEP DIVE: When designing in the players-distance category, two things are non-negotiable: First, there needs to be meaningful performance enhancements, and second, it must be delivered in a pleasing-to-look-at package. Wilson’s D9 Forged iron hits both those marks.
Key to achieving those was to arrive at a head shape and design that would lower the center of gravity position, producing a higher launch angle that would lead to a more desirable landing angle.
To produce those attributes, Wilson needed to re-design its “power chamber.” The power chamber is located inside the clubhead and is created by extending the urethane in the power holes (the through holes between the sole and cavity of the iron) into the cavity on the lower half of the face. This puts urethane directly in contact with the back of the face where contact occurs, reducing the sound and vibration produced by impact.
The company’s D7 Forged iron used a significant amount of urethane in the chamber. “That produced a great sound and feel, but made it difficult to get the CG low,” said Jon Pergande, manager of golf club innovation.
“Our goal was to reduce the size of the chamber and the amount of urethane. By still having some urethane contact the face and body, we didn’t sacrifice feel, but by using 40 percent less urethane—which weighs less than steel—there was more weight down low for a lower CG while also giving the face more room to flex.”
The clubhead is a two-piece construction with an 8620 carbon-steel body and a face that is 2.3 millimeters thick, allowing for plenty of rebound. On the sole of the club, Wilson’s hallmark “power hole” design remains, but it is far from simply a pickup from the previous iteration.
Wilson ran more than 3,000 automated computer simulations that resulted in over 1,000 potential power hole designs with varying permutations of the number per row; height; width, spacing and toe/heel bias. The primary goal: Reduce the variance between center and heel hits. What the simulations revealed is that the heel section is a very stiff area of the club and having a longer power hole—which is filled with a special urethane formulation—near that spot increases rebound. To help make the club more palatable to better players, there are no holes in the 8-iron through gap wedge where control is needed more than a few extra yards.
“The higher the handicapper, the more hits to the toe. The better the player, the greater the tendency is to make contact toward the heel,” said Pergande. “In the D7 Forged we had some challenges on the heel side so there was an added emphasis to improve performance all over the face, but particularly on the heel side of the face with this iron. This allowed us to do that.”
Available April 4, the D9 Forged irons use True Temper’s Dynamic Gold VSS steel shaft and UST Mamiya Recoil Dart graphite shafts as stock offerings. The stock grip is the Wilson Staff Lamkin Crossline. Price for a seven-piece set is $1,050 in steel and $1,150 in graphite.