At the far side a chain link holds two key rings. From that we get another chain link on the other side of the two key rings finishing the hold. That link is linked, then that link is linked. Then again the fallowing link is linked. 3 in total to join one set of two key rings to another set of two key rings. The pattern repeats.
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https://www.youtube.com/watch?v=MEdgScVhMtE
All right so instead of removing material from your finger tip for the length, just make sure the dart is as long as your finger tip and middle knuckle. I just remembered I could add a stronger spring.
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https://www.youtube.com/watch?v=RjK80vLsT4o
The title might come off a little strange, the build is meant to resemble the monkey's fist function. I was actually thinking about that song "My Friend the witch doctor", and it sort of has monkey lyrics don't it? ooh eeh ooh ah ah ting tang walla walla bing bang.
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https://www.youtube.com/watch?v=rDqstxNx8mk