Butterfly Butterknives

My new obsession is making foldingknives, butter foldingknives.
It started with a thought at work, I’m a woodshop teacher,  how can I make the common butterknife more interresting or challenging to make for the students?
It ended up with the folding butterknife

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One thing led to another…

Here’s the butterflybutterknife.

Do they work??

Well, see for yourself: