I should have added this one a while ago but I did a Geoffrey Butler a few years ago (it's in my signature below), I have another that's not in my signature but still to be done.Re:
I would add to brands we never see: brands we rarely see -
Bill Philbrook - unheard of by most but leading builder of the finest frames
Hobbs of Barbican - early innovator of fine lugs and bright colours
Roberts/Geoff Roberts - innovators, perfectionists, builders to professionals and Olympians alike, ran pro team
Allin - Peter Cobb, superb largely forgotten builder, famous professional son
Higgins - engineers above all
Major Brothers - touring bicycle innovators - largely forgotten
Geoffrey Butler - very famous shop, pro team, their best frames built by Roberts & Shrubb
Cliff Shrubb - record breaking bike builder
Ron Cooper - Like Bill Philbrook (whom he admired) a leading builder
Rk.
N.B mind you these makes might date me !!!
There's also a couple of unusalish European ones in my signature:
Francesco Moser
Jan Jansen
Navarro
Lucasa
Meral
Lejeunne
And dear to me because he was my local Frame builder, Ken James which I have two of.
Not all have threads unfortunately which is something I should really get round to