Hood / Dew Shield for Skywatcher 150/750 PDS

thingiverse

I like to do astrophotograhy from my balcony, because I am lazy, but I do have an annoying street lamp close by, so I wanted an additional lens hood with some flocking on the inside to minimize the effect of it for my Skywatcher PDS 150/750 newtonian. I designed this in FreeCAD with an inner diameter of 187.6mm, which is just enough to fit over the thickest part of the white metal rim and I created indentations that fit exactly over the outside screws, that fix the secondary mirror. There is a protrusion with a groove for rubber bands to fix the hood to each of the screws. The thickness of the hood is designed to be exactly 4 perimeters of 0.4mm which provides good stability. I bought an adhesive flocking mat at https://www.amazon.de/dp/B005FWUK44 out of which I cut a 120x589mm piece and stuck to the inside of the front edge of the hood. I printed with supports and brim because I've had issues with print bed adhesion of the anycubic filament. Both were a pain to remove since the entire thing does have *some* flex to it. Maybe it could have worked without, but I wouldn't want to risk it with a print of this size. I should have printed the outer perimeter with full speed and not the default 50%, since vibrations and print quality in general are not really an issue with this purely functional model. This would have saved me around 50% of the print time, so keep that in mind if you print it.