Summary: We, at SMOOTH Precision Pens, changed all of our titanium products to Grade 5 in early March 2023. We thought about using Grade 9 as it's the “middle ground” between Grade 5 and CP2 in terms of strength, but immediately scrubbed that idea. We want to provide our customers with the best of everything at all times and the BEST titanium for Everyday Carry (EDC) is Grade 5.
History: Titanium was first discovered in 1791 by the British clergyman William Gregor. He found a black, magnetic sand near the river in Cornwall, England, which he named. It was later recognized as a new element and named titanium after the Titans of Greek mythology.
Grade 5 vs Grade 9 vs CP2: Titanium is the most popular EDC material to date. This due to its high strength to weight ratio and durability, BUT did you know that there are different types of titanium? The three most common titanium’s used are: 6AL-V4 (Grade 5), Commercially Pure (CP2), and 3AL-2.5V (Grade 9).
Grade 5 is the strongest of the three and most heat-resistant. It also has the highest tensile strength, yield strength, and hardness. Simply put; Grade 5 titanium is the strongest commercially available titanium on the market.
CP2 titanium is a commercially pure titanium. It is the most commonly used titanium alloy in the industry due its low cost. It has good corrosion resistance and is the most ductile (softest) of the three.
Grade 9 is stronger than CP2, but not as strong as Grade 5. Other properties are “middling” as well such as: softness, corrosion resistance, and hardness.
Grade 9 is very popular for manufacturing as it’s ductile enough to extrude into shapes such as blocks and tubing. Tubing is great for pen manufacturing as it produces less chips than solid bar stock, but it’s still inferior to Grade 5 in terms of strength and durability.
Why We Use Grade 5 Titanium in Our Pens
All of our previous production issues stemmed from machining CP2 titanium. In general; the stronger the titanium, the better it machines, the better it polishes, and better the tool life.
Greater Machinability: CP2 and, to an extent Grade 9, don’t cut as “clean” as Grade 5. Sharp tools dull quickly due to the softness of the metal. The differences in machinability can be explained when cutting raw chicken vs cutting an apple. The chicken leaves remnants on the cutting blade at every slice, forcing you to repeat the cut multiple times to process the meat. The blade spends twice (or more) as much time cutting, thus increasing edge wear and forcing you to resharpen. On the other hand, an apple separates easily (clean) therefore spends little time in the cut thus allowing you to resharpen less often. The same thing happens when cutting CP2 (chicken) vs Grade 5 (apple). Machining CP2 takes multiple passes with the same tool causing premature wear. You can turn Grade 5 in one pass all day 😊.
Better Polishing: Harder metals polish better than softer metals. 6AL-V4 is harder than 3AL-V4 or CP2 therefore the surface finish “pops” harder than the other two. We’re offering polished pens now for our Limited Edition drops. We tried polishing CP2 and were not impressed then we tried Grade 5. Results speak for themselves.
Superior Durability: 6Al-V4 titanium is an excellent choice for applications that require a high-strength and durable material that can withstand harsh environments; like EDC. The only reason to not use Grade 5 is to cut costs and we don’t do that. We will never go back to CP2 or Grade 9. Yes, it’s more work to machine and cost ~33% more, but the pros far out weight the cons. We strive to give you the best and for EDC that’s Grade 5 titanium.