What is 'single-rod forging' of pure titanium and soft iron rods?

Golfers of all skill levels have a special admiration for muscleback irons. The irons are superior in functionality with their advanced maneuverability and difficulty, together with their biting, solid feel when hitting. But the irons’ presence when put into the golf bag, or should I say their dignified and elegant appearance, is something exceptional that sets apart from others.

The concept behind the C01 irons was to maximize the advantages of musclebacks while incorporating forgiveness. Although it is not that difficult to increase distance and forgiveness, these would be pointless if the feel of hitting and maneuverability that are the attractive features of musclebacks are lost. PROTO-CONCEPT sought to create irons that golfers would perceive as "cool" and yet be easier to use than they appear.

To achieve this goal, we adopted the "single-rod forging method" that incorporates pure titanium. As the name implies, pure titanium is built in the soft-iron rod to formulate a forging method in which two metals with different hardness and properties are forged as one. By adding a generous 25 grams of pure titanium with light specific gravity to the clubhead of the iron, weight is distributed around the perimeter and the center of gravity is positioned deeper, which increases forgiveness to mis-hits and makes it easier to increase ball flight.

This is what I want golfers to imagine realistically. In this method, a soft iron rod with pure titanium inside is pressed under high pressure to form the shape of an iron. When doing so, the titanium inside the clubhead is molded to the exact position and thickness as intended the moment it is forged. For example, the thickness of the soft iron area on the face side is secured well to assure superior feel when hit, and all the different thicknesses are finished as calculated. This requires extraordinary manufacturing technology.

ncreasingly more irons these days are produced using methods such as inserting different materials into the soft iron body and covering it with a face material, or molding separate parts and forging them together to attain performance. However, the C01 irons are currently the only irons in the world crafted with this single-rod forging method. Yes, this method is that technically difficult.

There have actually been irons in the past that have attempted to incorporate built-in titanium in the 2000s. The amount of titanium at the time was only 6g. In addition to failing to fully demonstrate performance, the area using hard titanium worsened feel. Therefore, these irons were never supported by professionals as well. This proves that you will not be able to develop a good club if you do not have the manufacturing technology necessary to maintain the balance of the club, no matter how superior the design concept is.

The C01 irons have a slightly larger head than conventional muscleback irons, and actually have the same forgiveness as cavity backs. The numbers with built-in titanium (#5-#7) and the with integrated soft-iron forging (#8-PW) use the softer S20C iron and soft S25C iron, respectively, to pursue a consistent feel and sound across the irons. This attention to detail is what makes a definitive difference in how the clubs perform as an iron set.

The C01 is the culmination of a globally unprecedented and advanced manufacturing process and PROTO-CONCEPT’s design philosophy, and we are proud to have created the best irons ever. I hope that many golfers who are dream of owning a muscleback will try these irons and feel the true value of a new generation of muscleback irons.

PROTO-CONCEPT Brand Producer
Yasufumi Kawasaki