Making a telescope for a pirate costume I am making a pirate outfit. I need to make a simple spyglass for it. I am opting for no sew but if I have to I will sew stuff I need for the outfit. This isn't for Halloween, just for fun and I like pirates so.

I only have cardboard and paper and fabric(I suppose I cold knit myself a square and tie it or something since I do have yarn) and the only source I have of cardboard tubes is toilet paper and paper towels. I don't want to waste them simply to get my tubes needed.

However I will store these tubes in a box so that I can use them. I have tape and glue to stick them on with. So how many cardboard tubes will I need to make the telescope and of what sizes?
A retracting telescope typically has 3 or 4 segments that retract into one another,



although the insecure pirate may feel the need to get a longer one.



The key features of the section diameters is that they slide easily past one another but will not fall apart when extended. In other words, you need a "stop" that prevents the larger segment from completely sliding off the next smaller one that's inside.

Assuming you have a method for building that stop, the tubes should ideally have a diameter difference of 1-10mm. A set of tubes with larger size gaps can still be used, but the extended telescope might look sloppier (the cumulative gap will cause more drooping, as in Jack Sparrow's overly long telescope above).