With the S in a Chevron & the initials RS(if that is what is near the lower rib on the underside of the left tube) then the tubes were sourced from the Schilling forge and Robert Schlegelmilch was the tubeset knitter. I'd say the rest was performed inhouse by H.A. Lindner's mechanic pool.

No worries on the radius as it was just a point for measurement. How long was the water table/action flats?

Kind Regards,

Raimey
rse