(click the image to enlarge)
The chart above has measurements for common Sousaphone parts, bore sizes and weights. It is a great reference for repair techs who need to know the thread size of a particular part.
It is a good tool for a parent or band director if you lose a screw just before the parade and you don't have time to get a replacement from the music shop, you might be able to make a trip to the hardware store and find something that will get you by until you can have the horn properly repaired. Parents, players and band directors can also compare weight if they have younger or smaller students who might not be able to handle something like a Conn 20K.
The list is currently incomplete. I have been putting it together a little every day and taking measurements as I get my hands on horns and parts. I will update the list as new information comes in. This list is also only part of a larger list that will contain RARE Sousaphones like Martins and Jumbos!!! I will post the FULL list at a later date. The list provided only includes common horns in BBb.