External sleeve tubing connectors

Some tubing connectors that slide over the outside. If you treat Blender units as 1 inch, then I think they're sized for 1/2 inch tubing. There should be a stop for the tubing to rest against internal to the sleeve. (I'd also think it's possible to make these work for other sizes by scaling. YMMV.)

Connectors so far:
3-way Corner
5-way star
4-way flat intersection
3-way T-connection
5-way (4-way crossing with riser)
4-way Corner Vert (Same as T-connection with riser)
6-way XYZ Axes cro