This hidden blade is based off of Ammnra's blade and features the DA-OTF(Double Action- Out The Front) Mechanism to propel the blade inward and outward with the flick of your wrist. I tweaked the hidden blade to make it operate smoother and fit more comfortably on your forearm. I have high hopes of eventually selling these bad boys to fellow cosplayers and Assassin's Creed fans.
The Mechanism: go here for an OTF Knife explanation. I recreated this mechanism by basing it off of someone called Amnnra. He does not sell his creation and I want the public to be able to have it. Anyway, if you want to see this in action check out one of his videos here.
His functions almost the exact same to this one except this one has gotten the kinks worked out and has a two tier extension, which allows for a longer more realistic blade.
This is basically what happens inside the blade casing: A piece of string is attached to a ring on one side and a rubber band on the other. The rubber band and string rap around a wheel and turn it when the ring (attached to finger) is pulled. When the wheel turns it activates the OTF mechanism which propels the blade forward. There is a special piece that locks the tiers so they dont retract unwantedly. To retract it you simply pull the string again and the OTF mechanism will retract it. If this made no sense to you, click the links of the words above. they will direct you to videos that will help you understand. :)