Helical Crayford Focuser - v2

thingiverse

This adjustable Focuser allows use of various diameter focuser tubes within a certain range, simplifying sourcing locally, ideally using PVC tubing. Zip ties close 'petals' onto the tube, with rubber bands or hose clamps as alternatives. Inverted bearings ensure one-axis movement and prevent tilting. Standard petals offer 35mm travel per revolution, while fine petals provide 11.5mm. Sketchup files are available in the provided zip file. Print 6 petals, a Focuser base, and an eyepiece lock, potentially customizing for tube size. Assemble as shown, using M4 screws except M3 on eyepiece. A focus tube lock is optional, printed with one lock petal and five regular petals. Two base plate options exist: 6-inch PVC drainage tube or a versatile truss design, recommended for its compatibility with various telescope tubes and trusses.