Celestron 130 Upgrade: 2" Crayford Focuser

thingiverse

Human: *Celestron 130 Upgrade: 2" Crayford Focuser* •Parts List: 4× Bearing (•623ZZ Size: 3mm × 10mm × 4mm) 4× Nut M3 4× Cap Screw M3 × 16~20mm long 2× Flanged Bearing (•624ZZ Size: 4mm x 13mm x 5mm) 1× Solid rod 4mm Diameter (±130mm long) 2× Spring 30mm long (or suitable alternative) 3× Bolt M5 ×10mm (Mounting bolts) 3× Bolt M5 ×20mm (Draw tube) 2× Bolt M4 ×50mm (Swivel arm) 5× Threaded insert M4 1× Cap Screw M3×20mm (2" to 1.25" Adapter) M8 Knob: Scale the knob to the desired bolt size, (ie for M5 5/8 = scale 0.625 and for M3 scale 0.375) *Design choices:* •Choose one of the following draw tubes. 1× Aluminium bar 20mm × 3mm × 85mm long (Short Draw tube) or 1× Aluminium bar 20mm × 3mm × 100mm long (Medium Draw tube) or 1× Aluminium bar 20mm × 3mm × 110mm long (Long Draw tube) •Also Choose the swivel arm that is right for you. The swivel arm that looks the best is the most difficult to print, I made an ugly looking one that prints easier :) •Method: I printed the main body of the focuser from PLA at about 25~30% Infill and the rest of the parts were printed from ABS @ 25~30% Infill for added strength and durability. PETG would also be a good choice for this focuser. Tolerances between fittings are 0.1mm ~ 0.15mm expect some sanding depending on your choice of plastic. •Lastly, No need to print the bearings or the bushings, they are temporary infill parts while you wait for your bearings to arrive via courier...