This weekend’s telescope improvement project: design & 3D-print collimating bolts for my C11 SCT.

Collimating (alignment of all the optical elements) is important for normal viewing through the eyepiece and absolutely critical for astrophotography & webcasting when using hi-spec astro-cameras.

The collimation bolts in this older C11 (Nexstar) SCT had a cross-head which required adjustment using a Philips screwdriver - not very practical and also a considerable risk of damaging the telescope specific, & expensive, corrector plate on the front of the scope.

So ..... after several design iterations using Fusion 360 I succeeded in printing the threaded bolt using tough ABS (“Lego brick”) filament inserted into a wide cap (PLA filament) - which makes adjustment in the cold & dark a doddle.