harryagain wrote:

"Andy Burns" wrote:

drill and tap a dozen
holes into stainless steel tube, this is 2mm wall thickness, 42mm diameter
handrail

It's not practical to tap metal only 2mm thick for an M5 screw.
SS is a bugger to anything with, esp.tapping threads.

Even though it *is* what is recommended by the manufacturer (they only
use rivnuts or flowdrilling for M6 and M8 holes and the brackets require
M5) I've taken on-board the difficulties of tapping, and have ordered
some A2 M5 rivnuts and a setting tool - plenty to practice with.