OpenAstroTracker 500mm lens Walimex Mount, Adapter, Focuser & Blend by chris_r_schmidt

Last crawled date: 4 years, 7 months ago

This assembly included a modified mount used twice (front&back) for a 500mm Walimex lens.
Assembly includes:
one mount that integrates a focuser assembly
focuser assembly driven by a small stepper motor 28BYJ-48
Camera mount is for the RaspberryPi HD camera
huge blend that is a remix and screws into the filter adapter
guides are 2mm hobby RC car axles and drive thread and nut are M6x70.
Although I include the STL´s - please use the cad files to customize the diameter to fit your lens ( i.e. Samyang or other) - mine turned out a bit loose required a rubberband to create a super tight fit.
I use the Ardufocuser firmware by jbrazio to control this + guidescope focuser in EKOS/KSTARS. https://github.com/jbrazio/ardufocus
I had tried using a follower focus approach and found the mechanical resistance of the lens to require more power than I cared to invest in, this seemed a lighter weight solution.
Credits:
2020_profile.scad from slurked
28byj48stepper.scad from Russ Hughes - has a small inaccuracy around blue plastic bit
parametric_involute_gear_v5.0.scad from GregFrost - to design gears (not easy)
threadlib_solid.scad from Johnny Cernato
fillet.scad can´t find the source
ISOThread.scad //by RevK @TheRealRevK
libPiCam.scad //J.Beale
remixed Blend: thingiverse.com/thing:4492847 by risomaster
remixed Lens Base Brackets: https://www.thingiverse.com/thing:2992708 by barbelturique