An early design for a ballpoint pen. I think I wrote it at a pen show two or three years ago... The mechanism was a rotating mechanism, and combining my limited knowledge, I could only think of a cross type for the core rotating mechanism.
The cross type has a twist mechanism on the head side, so if the head and tail are almost one piece, it is impossible to replace the refill. After much trial and error, I came up with this picture. However, the center part was not concentric...I thought I would make it tapered to match.
The shape is smart, but the structure is not smart, so it's not very neat.
Since there was nothing I could do about this, I decided to let the idea sit for a while.
I thought of a twisted part so I made it.
I don't really understand how the lead of a ballpoint pen comes out. So I made a Parker refill with a step difference and checked at what length the lead comes out.
This time, our pencils were sold by 590&co, the mecca for pencils. Thank you.