Part of the poseable arm design that I am working on requires that an arm section that can twist along its length. In the original version that meant that two square sections were butting up against each other. When the parts were twisted 45 degrees the big step between the parts didn’t look good. To get around that I came up with a tube section that starts with a square at one end and tapers down to an octagon at the other. The point where the two ends meet now looks a lot neater.

I can use this design to connect to a tube using a rotating slug wrapped in a card sleeve.

With the newly designed parts put together I now have a much neater version of  six-axis arm.

The addition of a sleeve section tidies up the hand joint to complete the arm design. Next step, I’ll put together a clean version of the model to make sure all the proportions are correct.