This build is inspired by the Baby Dob 114mm F8 project from scopemaking.net website. Also, quite useful reference is a comprehensive Stellafane's tutorial on building a Dobsonian telescope.
The primary and secondary mirrors are bought on eBay. The primary is a spherical mirror with 114mm/4.5" diameter and 900mm focal length (F8).
Holds the primary mirror in place.
This thing holds the secondary mirror in place just below the focuser. It is made from a section of a beech wood dowel rod 25mm in diameter (24mm would have been better as the minor diagonal of the secondary mirror is around 24mm). The vanes are 9cm long sections of metal cutting blades. The three M4 screws are used in the collimation of the secondary mirror. Needs to be painted in black with matte finish.
The focuser is made out of a PG-36 cable gland. The locking nut needs to be worked out with a utility knife in order to widen the opening to 32mm so it can receive a 1.25" eyepiece. The base locking nut which is threaded needs a curve ground in it so it fits the tube snugly. It functions as a (pseudo) helical focuser -- you turn the focuser to change focus.
The Super Plossl 26mm eyepiece is made out of 25mm-to-20mm PP-R pipe fitting, a film canister and an eypiece lens set from Surplus Shed (two achromats and one DCX). The spacers for the lenses are cut from the film canister and fixed with a dab of superglue.
The eyepiece and the objective lens are taken from a broken binoculars. The new tube is a PVC electrical conduit. Made to fit using some blue eletrical tape and a little bit of hot gun persuasion.
A piece of the main telescope tube as a base, a piece of wood, a 50mm waste water pipe with six M4 screws.
A 160mm diameter waste water tube. Seen here with abrasive papers taped to it for grinding the focuser locking nut. Already painted inside with a black matte finish spray can (after spraying with plastic primer first).
Centering the spider using a centering tool inserted in the focuser and a paper template.
A view through the centering tool. You can see the paper template reflection in the secondary mirror.
