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Old July 18th, 2016, 04:43 AM   #7
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Originally Posted by dvw View Post
Single biggest reason for breaking a Snyder kingpin is misadjusted pivots. The Snyder parts are plenty strong enough but if the pivots are off, usually too short, they'll break.

Contrary to popular belief, the titanium kingpin is not stronger. Quite the opposite. Titanium is stronger for a given weight than steel. I've seen them bend and break. And the Snyder Titanium kingpins have been gone for several years.

The Kingpin from a Bont Infinity will fit, however, if you want titanium.
DVW, while it's true that the strongest alloy steels can easily be heat treated to a higher strengths than Grade 5 titanium alloys, higher strength is NOT always going to make a skate part hold up better. Higher strength parts can often be more brittle and lack the toughness needed to handle the shock loading of skating duty, thus fracturing where a less strong part might just flex, but not fail.

The highest strength readily available Ti alloy for threaded fastener parts tops out at about 150KSI, which is stronger than normal Grade 8 steel fasteners. However, Ti fasteners in the 125-130KSI tensile strength range are more the normal - just a bit lower than Grade 8 steel.

Higher tensile strength is not always better. Some lower strength alloys can have other properties that make them superior for skate parts - like toughness (better yield strength with more elongation before deformation), fatigue strength (better tolerance of cyclical bending loads without cracks propagating across the parts); and better corrosion resistance.

Titanium Facts from TiKORE INDUSTRIES.
Comparison of Grade 5 & 8 Steel vs 7075 Aluminum vs Grade 5 Titanium

Grade 5 Alloy Steel (commonly used on automobiles for lug nut and lug bolt applications)
Yield Strength: 92,000psi
Ultimate Tensile Strength: 120,000psi
Shear Strength: 72,000psi
Density: .284 lb/in^3

Grade 8 Alloy Steel (used for lug nuts and lug bolts in high strength applications):
Yield Strength: 130,000 psi
Ultimate Tensile Strength: 150,000psi
Shear Strength: 90,000psi
Density: .284 lb/in^3

7075 Aluminum (used on various automobiles for lug nut and lug bolt applications):
Yield Strength: 73,000psi
Ultimate Tensile Strength: 83,000psi
Shear Strength: 48,000psi
Density: .102 lb/in^3

Grade 5 6AL-4V Titanium (Tikore's preferred material):
Yield Strength: 128,000psi
Ultimate Tensile Strength: 138,000psi
Shear Strength: 79,800psi
Density: .160 lb/in^3

Additional note: Titanium has an extremely high resistance to corrosion.

As presented above, titanium bolts/nuts have a strength that is very comparable to grade 8 steel bolts/nuts that are used in high strength applications. Furthermore, based on the density figure above grade 5 titanium is 45% lighter than steel components.

Rollin' on AIR

Last edited by Armadillo; July 19th, 2016 at 07:21 AM.
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