A telescope I made for my daughter, she wanted it 'rainbow' so I printed each piece in a different colour.
Print one of each piece. I printed these at 0.2mm layer depth. The walls are 1mm wide, which on my printer is 2 walls and no fill **looking at the images, you may need to flip the eyepiece so you can print it without support.
You will also need two pieces of clear perspex, one at 65mm diameter and one of 30mm diameter. I am not 100% sure but I think this would actually work as a telescope with some magnifying lenses (it is a future job to find out).
To put together:
Place the 65mm perspex in the 'end' of the telescope, stack pieces 1 through 6 in each other and then place on the 'end' piece. Part 1 should fit snugly in to the end piece and you can glue (I used acetone) this in once you are sure that you have it right.
Then place the 30mm perspex in the eyepiece, extend the telescope and give it a bit of twist so that it does not collapse, then glue (again I used acetone) the eyepiece to the end of piece 6.
Once the glue has dried you can go ahead, get your parrot on your shoulder start talking pirate speak and be ultra cool with your own custom printed telescope. A slight twist and pull will ensure that it doesn't collapse on you while you are trying to look through it and a good whack will collapse it when you are ready.