I had a couple of questions about the string action on my banjos from people who want to play clawhammer.
Here are the measures of the action of my instruments:
Bart Reiter Standard: at the 17th fret (approximately where I play) 5,05 mm. Height of bridge 16,97 mm.
Enoch Tradesman: at the 15th fret (approximately where I play) 5,32 mm. At the scoop 8,41 mm. Height of bridge 15,30 mm
S. S. Stewart Special Thoroughbred: at the 20th fret (approximate where I play) 6,40 mm. Height of bridge 16,30 mm.
Mind you, I have my strings widely spaced (at the bridge: 50,26 mm) on all my banjos. That means, that the 5th string runs parallel with the edge of the fretboard, facilitating an easy to catch with the thumb.
For playing clawhammer as well as two-fingerpicking I recommend at least 5,00 mm action over the high end of the fretboard (where it meets the rim of the banjo head). The relatively high action makes drop thumbing easier.
People who themselves do not play traditional clawhammer or two-finger styles and who may have only experience for example with melodic high-up-the-neck bluegrass picking, may tend to prefer a lower action.
The banjos I saw at the 2018 Banjoree clawhammer workshops of mine, all looked fine. If however you have questions, approach me on any of our workshops, and let’s have a good look on your banjo.