Knurled pin fastener and method of forming a knurled pin fastener
A pin fastener includes a body having a first end that extends to a second end through an intermediate portion. The intermediate portion includes a first substantially constant diameter section that extends from the first end toward the second end, a first tapered section that extends from the first substantially constant diameter section, a second substantially constant diameter section that extends from the first tapered section, and a second tapered section that extends from the second substantially constant diameter portion to the second end. The pin fastener further includes a knurled section formed in the second substantially constant diameter portion.
1. A pin fastener comprising:
a body including a first end that extends to a second end through an intermediate portion, the intermediate portion including a first substantially constant diameter section that extends from the first end toward the second end, a first tapered section that extends from the first substantially constant diameter section, a second substantially constant diameter section that extends from the first tapered section, and a second tapered section that extends from the second substantially constant diameter portion to the second end; and
a knurled section including a plurality of helical grooves formed on the second substantially constant diameter portion, wherein the plurality of helical grooves include first and second flank portions joined by a radius portion, the plurality of helical grooves including an angle between the first flank portion and the second flank portion.
2. The pin according to claim 1 , wherein the plurality of helical grooves include a pitch of between about 20° and about 40°.
3. The pin according to claim 1 , wherein the plurality of helical grooves include a pitch of between about 25° and about 35°.
4. The pin according to claim 1 , wherein the plurality of helical grooves include a pitch of about 30°.
5. The pin according to claim 1 , wherein the angle between the first and second flank portions is between about 80° and about 120°.
6. The pin according to claim 1 , wherein the angle between the first and second flank portions is between about 90° and about 110°.
7. The pin according to claim 1 , wherein the angle between the first and second flank portions is about 100°.
8. The pin according to claim 1 , wherein the first tapered section includes a taper of between about 4° to about 12° from the first substantially constant diameter section toward the second substantially constant diameter portion.
9. The pin according to claim 1 , wherein the first tapered section includes a taper of between about 6° to about 10° from the first substantially constant diameter section toward the second substantially constant diameter portion.
10. The pin according to claim 1 , wherein the first tapered section includes a taper of about 8° from the first substantially constant diameter section toward the second substantially constant diameter portion.
11. The pin according to claim 1 , further comprising: a head positioned at the first end.
12. The pin according to claim 1 , further comprising: a tip provided at the second end.
13. The pin according to claim 12 , wherein the tip comprises a ballistic point having a generally ogive profile.
14. A method of forming a pin fastener, the method comprising:
creating a pin body having a first end that extends to a second end through an intermediate portion;
forming the intermediate portion to include a first substantially constant diameter section that extends from the first end, a first tapered section that extends from the first substantially constant diameter section, a second substantially constant diameter section that extends from the first tapered section, and a second tapered section that extends from the second substantially constant diameter portion to the second end; and
knurling a plurality of helical grooves in the second substantially constant diameter portion, the plurality of helical grooves including first and second flank portions joined by a radius portion, the plurality of helical grooves having an angle between the first flank portion and the second flank portion, the angle being between about 80° and about 120°.
15. The method of claim 14 , wherein knurling the plurality of helical grooves in the second substantially constant diameter portion includes forming the plurality of helical grooved having a pitch of between about 20° and about 40°.
16. The method of claim 14 , further comprising: tapering the first tapered section between about 4° to about 12° from the first substantially constant diameter section toward the second substantially constant diameter portion.
17. The method of claim 14 , further comprising: forming a head at the first end and a ballistic point having a generally ogive profile at the second end.