A poor man's refractor telescope

thingiverse

# A poor man's refracting telescope This project will let you explore the basics of creating your own DIY telescope. The setup is designed to be a telescope in its simplest form. The project is designed to help beginners learn about the components of a telescope and how they work together The telescope is designed to be both easy to print and easy to assemble. ## What you need * An objective (lens + printed structure) * An 1,25" eyepiece * An optical tube * A focuser tube ## The optical tube The optical tube provides the main structure for the telescope. The length of the optical tube depends on the focal length of the objective lens. The optical tubes main task is to separate the focuser tube and the objective lens with a distance that is slightly shorter than the focal length of the objective lens. Print the optical tube that matches the focal length of your objective lens. | stl file | focal length (mm) | |----------------------------|--------------------------| | optical-tube_300.stl | 300 | | optical-tube_400.stl | 400 | | optical-tube_500.stl | 500 | ## The objective lens The objective of a telescope is the part that focuses the incoming light so that it can be magnified by the eyepiece. In a refracting telescope, the objective consists of a glass lens. The quality of the objective lens is the most decisive factor if the telescope will provide you with a sharp or blurred image. This poor man's telescope however lacks the part for precise adjustments of the focuser tube. The purpose of this telescope is to let you play around and explore the most basic feature of a telescope. The recommendation is to buy a cheap lens, so that it doesn't matter if the lens get damage during assembly. You may still be able to spot some of the bigger craters on the moon with a cheep lens. If you have the economics to by a achromatic lens from a well known vendor such as Thorlabs than you would be able to get a really sharp image using this telescope design. ## The objective The part that encloses the objective lens consists of two parts. One part that should be pushed onto the optical tube, and the other part that encloses the lens. The part that encloses the lens should be pushed onto the part that connects to the optical tube. The part that encloses the lens should match the diameter and the thickness of your objective lens. Print the enclosing part that best matches the lens you have, place the lens in the enclosure and press it on to the other objective part that will connect to the optical tube. Print the enclosure that best matches your objective lens. The enclosure should have a slightly higher diameter then the lens, so a lens with a diameter of 50 mm should be printed with a enclosure with a diameter of 51 mm. | stl file | diameter (mm) | edge thickness (mm) | |--------------------------------------- --|---------------------|------------------------------| | lens-enclosure_508_18.stl | 50,8 | 1,8 | | lens-enclosure_510_18.stl | 51,0 | 1,8 | | lens-enclosure_511_18.stl | 51,1 | 1,8 | | lens-enclosure_508_21.stl | 50,8 | 2,1 | | lens-enclosure_510_21.stl | 51,0 | 2,1 | | lens-enclosure_511_21.stl | 51,1 | 2,1 | | lens-enclosure_508_33.stl | 50,8 | 3,3 | | lens-enclosure_510_33.stl | 51,0 | 3,3 | | lens-enclosure_511_33.stl | 51,1 | 3,3 | | lens-enclosure_510_1101.st | 51,0 | 11,01 | | lens-enclosure_511_1101.st | 51,1 | 11,01 | Put a comment and I can generate more options for the enclosure part. ## The eyepiece Maybe you already have a 1.25 inch eyepiece that you can use. You could also print your own eyepiece using this project: [The poor mans eyepiece](https://www.thingiverse.com/thing:5889682) ## The focuser tube The focuser tube is the part the let you adjust the distance from the objective to the eyepiece. Print the size of the focuser tube that correspond to the focal length of the objective. | stl file | focal length (mm) | |----------------------------|--------------------------| | focuser_300.stl | 300 | | focuser_400.stl | 400 | | focuser_500.stl | 500 | ## The poor mans telescope This telescope is generated from the following poor mans telescope project. You can download the FreeCAD files for the telescope from the github page. [Github - 3d printable telescope](https://github.com/leonardsaers/3d-printable-telescope)