Spectroscope Com ...

The spectroscope that I've mentioned in previous entries was purchased off of Ebay several years ago, but it has never had a working slit assembly. The slit is a critical part of a spectroscope -- it controls the amount of light allowed into the instrument, and it's the illuminated slit whose image is viewed through the eyepiece.

I was able to purchase an adjustable slit assembly from the Surplus Shed online, however this assembly did not connect to my spectroscope. Thankfully, a friend of mine has a lathe in his basement & was kind enough to adjust the diameter of a critical component to the point where it would fit.

This is the result:



...and it works well too (I may post spectra in the future). I have no idea how the original slit assembly mounted to the spectroscope because there does not appear to be any threads or set screws, and this is the only real flaw in the current situation. While a friction fit works to a degree, it is loose & the slit is prone to rotating or sliding out & loosing focus. It the future i may have to drill and thread a hole in the telescope assembly to add a set screw. For now, however, the arrangement works well enough.