A little while ago I reported on my pre-release WTF Ti mini-pry bar that I managed to sweet talk Brad of TacticalKeyChains into sending me, as it was a second. Just recently my full order from the Kickstarter campaign arrived, and thought I should show off the pre-production version against the production models.I ordered both titanium and the chromium/molybdenum chromoly 4130 steel "stealth" version which has been Parkerized for shine and corrosion resistance. The main physical difference between the Ti and chromoly is the machining, in that the face of the pry-edge of the Ti versions is textured from the machining, where as the chromoly version is smooth finished, due to the requirements for working the different metals. I like them both, and have had no discernible difference in performance when prying, they both bite nicely.
I had the production WTF anodized to a rose-gold colour, as it was going to be a gift for Omega (which she put straight onto her key chain, along with her NuKo Tool TiGBi Skully ). The only real difference between the the production version of the Ti WTF, and my "seconds" version is the lanyard hole is not quite centered in the second. In theory this might weaken that end, but I can't imagine putting enough force on the lanyard hole to make that an issue.The Ti WTF's (made of Ti-6Al-4V) weigh 7.8g and the Stealth WTF (made of AISI 4130) weighs more at 11.5 grams, which is a small price to pay considering the benefits.
Brad has kindly provided some metallurgical stats on the materials he uses for the WTF's. The Ti-6Al-4V - has an Ultimate Tensile Strength of 138,000 psi and an elasticity modulus of 16,500 ksi, which means it is very very resilient, and springy. It will flex under stress.
TheChromoly 4130 has a Ultimate Tensile Strength - 97,200 psi but has an elasticity modulus of 29,700 ksi meaning it is not quite as resilient but VERY stiff.
Compare that against the aluminium 6061-T6 used for the basic WTF's which has an Ultimate Tensile Strength of only 45,000 psi and an elasticity modulus of 10,000 ksi which is to say, relatively soft.
The cromoly WTF has the advantage of being ferromagnetic, and the wrench bits will not "give" when working stubborn nuts. I really like my WTF's, i wear the golden "second" around my neck as a part of my EDC, and the chromoly version has found a place in my ZuluNylonGear CAOS admin pouch. These are brilliant little tools, and I'm glad I made the investment.
