DOB Knob

I've been using telescopes for most of my life and recently bought a 10" Apertura Dobsonian. This style of telescope has a bit of a learning curve and to make it easier to move, I designed this knob - a DOB Knob!

While designed for my 10" scope, it should also work with 8 and 12" models as well. First, print the knob and the optional cut washer using the recommended slicing and print settings. The washer allows for the knob to screwed down tightly without crashing into the collar.

Next, locate the short M4 screws around the collar on the opening of the scope. Remove the screw on lower edge (in the direction of the mount). Thread a 25mm M4 screw (available from Amazon) from the inside to the outside. Do this with the scope in a horizontal orientation so nothing gets dropped on the mirror. Slide the printed washer over the screw and align the "cut" side with the collar. Now thread on your DOB-Knob onto the exposed screw. This may require a bit of work to get started.

And voila