Golf club heads and methods to manufacture golf club heads
Embodiments of golf club heads and methods to manufacture golf club heads are generally described herein. In one example, a method of manufacturing a golf club head may include providing a golf club head having a face portion. The method may include determining a reference characteristic time value at a reference location on the face portion, determining a measured characteristic time value at each of a plurality of locations on the face portion, determining a differential characteristic time value at each of the plurality of locations, and altering a face thickness at a location where the differential characteristic time value is nonzero. Other examples and embodiments may be described and claimed.
1. A method of manufacturing a golf club head, comprising:
providing a body portion having a top portion, a bottom portion, a heel portion, a toe portion, a rear portion, and a front portion;
providing a face portion coupled to the front portion, the face portion comprising:
a front surface;
a rear surface opposite the front surface; and
a plurality of square face regions on the rear surface of the face portion, the plurality of square face regions defined by a plurality of vertical lines and a plurality of horizontal lines that intersect the plurality of vertical lines, the plurality of square face regions forming a grid of square face regions comprising a plurality of rows of square face regions and a plurality of columns of square face regions;
determining a reference characteristic time value at a reference location on the face portion, the reference location being located within a sweet spot on the face portion;
determining a measured characteristic time value at each of a plurality of locations on the rear surface of the face portion, the plurality of locations corresponding to intersection points between the plurality of horizontal lines and the plurality of vertical lines;
determining a differential characteristic time value at each of the plurality of locations, each differential characteristic time value being determined by subtracting the reference characteristic time value from the measured characteristic time value; and
altering a face thickness of the face portion at a location where the differential characteristic time value is nonzero,
wherein the square face regions of each row are linearly aligned,
wherein the square face regions of each column are linearly aligned,
wherein each square face region is defined by an intersection of two vertical lines of the plurality of vertical lines and two horizontal lines of the plurality of horizontal lines,
wherein each square face region includes a first corner thickness at an intersection of a first vertical line of the plurality of vertical lines and a first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a second corner thickness at an intersection of a second vertical line of the plurality of vertical lines and the first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a third corner thickness at an intersection of the first vertical line of the plurality of vertical lines and a second horizontal line of the plurality of horizontal lines,
wherein each square face region includes a fourth corner thickness at an intersection of the second vertical line of the plurality of vertical lines and the second horizontal line of the plurality of horizontal lines,
wherein each square face region includes an average thickness determined by summing the corresponding first, second, third, and fourth corner thicknesses and dividing by four, and
wherein two or more of the square face regions have differing average thicknesses.
2. A method as defined in claim 1 , wherein altering the face thickness comprises adding material to the location where the differential characteristic time value is positive.
3. A method as defined in claim 1 , wherein altering the face thickness comprises removing material from the location where the differential characteristic time value is negative.
4. A method as defined in claim 1 , wherein altering the face thickness comprises adding material to a first location where the differential characteristic time value is positive and removing material from a second location where the differential characteristic time value is negative.
5. A method as defined in claim 1 , wherein the grid comprises at least four rows of square face regions and at least six columns of square face regions.
6. A method as defined in claim 1 , wherein neighboring horizontal lines of the plurality of horizontal lines are spaced apart by a distance of about 3 millimeters (mm) to about 10 mm, and wherein neighboring vertical lines of the plurality of vertical lines are spaced apart by a distance of about 3 mm to about 10 mm.
7. A method as defined in claim 1 , wherein the reference location is a geometric center of the face portion.
8. A method of eliminating one or more hot spots on a face portion of a golf club head, the method comprising:
providing the golf club head having the face portion, the face portion comprising a front surface and a rear surface opposite the front surface, and a plurality of square face regions on the rear surface of the face portion, the plurality of square face regions defined by a plurality of vertical lines and a plurality of horizontal lines that intersect the plurality of vertical lines, the plurality of square face regions forming a grid comprising a plurality of rows of square face regions and a plurality of columns of square face regions;
determining a reference characteristic time value at a reference location on the face portion;
determining a measured characteristic time value at each of a plurality of locations on the rear surface of the face portion, the plurality of locations corresponding to intersection points between the plurality of horizontal lines and the plurality of vertical lines;
identifying a hot spot on the face portion as a location where the measured characteristic time value is greater than the reference characteristic time value; and
increasing a face thickness of the face portion at the location of the hot spot,
wherein the square face regions of each row are linearly aligned,
wherein the square face regions of each column are linearly aligned,
wherein each square face region is defined by an intersection of two vertical lines of the plurality of vertical lines and two horizontal lines of the plurality of horizontal lines,
wherein each square face region includes a first corner thickness at an intersection of a first vertical line of the plurality of vertical lines and a first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a second corner thickness at an intersection of a second vertical line of the plurality of vertical lines and the first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a third corner thickness at an intersection of the first vertical line of the plurality of vertical lines and a second horizontal line of the plurality of horizontal lines,
wherein each square face region includes a fourth corner thickness at an intersection of the second vertical line of the plurality of vertical lines and the second horizontal line of the plurality of horizontal lines,
wherein each square face region includes an average thickness determined by summing the corresponding first, second, third, and fourth corner thicknesses and dividing by four, and
wherein two or more of the square face regions have differing average thicknesses.
9. A method as defined in claim 8 , wherein increasing the face thickness at the location of the hot spot comprises increasing the face thickness until the measured characteristic time value is less than 257 milliseconds.
10. A method as defined in claim 8 , wherein the face portion is a separate face portion that is coupled to a body portion of the golf club head to enclose an opening in a front portion of the body portion.
11. A method as defined in claim 8 , wherein the face portion is integrally formed with a body portion of the golf club head.
12. A method as defined in claim 8 , wherein increasing the face thickness comprises adding material through additive manufacturing.
13. A method as defined in claim 8 , wherein the reference location is located within a sweet spot on the face portion.
14. A method as defined in claim 8 further comprising determining a differential characteristic time value by subtracting the reference characteristic time value from the measured characteristic time value, wherein increasing the face thickness at the hot spot comprises adding between 0.02 millimeters (mm) and 0.08 mm of material per positive unit of the differential characteristic time value.
15. A method of manufacturing a golf club head, comprising:
providing a golf club head having a face portion, the face portion comprising a front surface and a rear surface opposite the front surface, and a plurality of square face regions on the rear surface of the face portion, the plurality of square face regions defined by a plurality of vertical lines and a plurality of horizontal lines that intersect the plurality of vertical lines, the plurality of square face regions forming a grid comprising a plurality of rows of square face regions and a plurality of columns of square face regions;
determining a reference characteristic time value at a reference location on the face portion;
determining a measured characteristic time value at each of a plurality of locations on the rear surface of the face portion, the plurality of locations corresponding to intersection points between the plurality of horizontal lines and the plurality of vertical lines;
identifying an underperforming location on the face portion as a location where the measured characteristic time value is less than the reference characteristic time value; and
decreasing a face thickness of the face portion at the underperforming location,
wherein the square face regions of each row are linearly aligned,
wherein the square face regions of each column are linearly aligned,
wherein each square face region is defined by an intersection of two vertical lines of the plurality of vertical lines and two horizontal lines of the plurality of horizontal lines,
wherein each square face region includes a first corner thickness at an intersection of a first vertical line of the plurality of vertical lines and a first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a second corner thickness at an intersection of a second vertical line of the plurality of vertical lines and the first horizontal line of the plurality of horizontal lines,
wherein each square face region includes a third corner thickness at an intersection of the first vertical line of the plurality of vertical lines and a second horizontal line of the plurality of horizontal lines,
wherein each square face region includes a fourth corner thickness at an intersection of the second vertical line of the plurality of vertical lines and the second horizontal line of the plurality of horizontal lines,
wherein each square face region includes an average thickness determined by summing the corresponding first, second, third, and fourth corner thicknesses and dividing by four, and
wherein two or more of the square face regions have differing average thicknesses.
16. A method as defined in claim 15 , wherein decreasing the face thickness at the location of the underperforming location comprises decreasing the face thickness until the measured characteristic time value is between 239 milliseconds and 257 milliseconds.
17. A method as defined in claim 15 , wherein decreasing the face thickness comprises removing material from the face portion at the location by milling.
18. A method as defined in claim 15 , wherein the golf club head comprises a hosel portion extending from a body portion of the golf club head, the hosel portion comprising an interchangeable hosel sleeve.
19. A method as defined in claim 15 , wherein the golf club head has a volume greater than 300 cubic centimeters.
20. A method as defined in claim 15 further comprising determining a differential characteristic time value by subtracting the reference characteristic time value from the measured characteristic time value, wherein decreasing the face thickness at the underperforming location comprises removing between 0.02 millimeter (mm) and 0.08 mm of material per negative unit of the differential characteristic time value.