Research help - Profiles/bores/type of bugle.

[2ba4t]

I am still trying to create a set of diagrams showing clearly and accurately the different bugle profiles of all the various ‘types’ of tubas, including where the valves are placed. Then I need to see if there is a consensus on the difference this all truly makes. The rate of expansion and where this occurs does not seem to be clearly and fully set down anywhere. Clifford Bevan certainly covers this, as we have discussed on this site, but is there more detail, please? There seems a clear difference between the Saxhorns, Czech/Russian tubas, pre-WWII British tubas, Verdi's tubas etc etc, all the various brilliant USA makes - but can this be clearly quantified?
Is there anyone out there who can please help. It is a good lockdown activity.