Styles of Curved Vane Spiders

Picture	Name	Stability	Installation & Adjusting	Sizing
	Single Half Curved Vane Spider	Shakes side to side when telescope is bumped.	Difficult to adjust to the center of the tube.	Must be very precise, and generally does not allow for adjustments for out of center mirror cells or tube alignments.
	Single Curved Vane Loop	Tends to shake side to side in what I would call the Jello effect.	Not to bad, a little difficulty adjusting to the center of the tube..	Must be precise, or use slotted screw holes on an angle bracket which usually causes minor diffraction.
	Three Curved Vane Spider	Very stable even when scope is bumped.	Easy to install. The vanes press against the walls of the scope allowing the spider to be pushed in place first and fastened after checking its position.	Not to critical since the spider can be inserted in a tube smaller than the spider and the difference is absorbed evenly by the vanes, centering itself fairly well.
	Four Curved Vane Spider	Very stable, excellent for Truss type scopes that often have four sides to attach to.	Easy to install. Can be pushed in place first, marked, and fastened.	Not very critical since the vane self centers fairly well.