This part
formatting link
slides freely on an axle, but I don't know how easy it would be to connect it to another axle. With a bit of experimentation you can get what you need, but its pretty bulky.
ROSCO
Anybody know of a part that slips onto a cross axle shaft
> and slides longitudinally while still transmitting torque?
> That is, in a long cross section it would look something like
> this:
>
> ##----------
> +++++### +++++++++++
> ##----------
>
> The part I'm interested in is on the left. It would probably
> have its own stub of cross axle shaft, connected to a sleeve with
> a long cross-shaped hole in it that fits (without friction) over
> another cross axle shaft, here indicated by +++++++++++ on the
> right. The idea is that the axle shaft on the right can slide in > and out:
>
> ##---------- ##----------
> +++++### +++++++++++ +++++### +++++++++++
> ##---------- ##----------
>
> But while the one part can slide in and out of the other, they
> can't turn with respect to one another, so turning one shaft
> would turn the other.
>
> Steve Summit
> snipped-for-privacy@eskimo.com