So recently I have put quite a bit of thought into how to hookblade work, and from what iv seen there have been many other blog posts that attemp to figure out how hidden blades, hookblades ect work. Most of the blogs include a small rige that goes around the finger that controls a pully which opens/closes the hidden blade/hookblade. Personally, I think this would be quite of a hassle when constantly contracting and retracting the blade, so I thought why not make a small pressure pad on the top of the mechanism that controls the opening. So when you move your hand back to activate the pressure pad, the blade shoots out until you release the pressure pad. Im sorry if my thoughts are jumbled, but if you can get the general idea of what i am thinking, please let me know your ideas.