"Andy Burns" wrote in message
o.uk...
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.


Well then that would work, no tapping required.
Be sure to make a good indent with a centre punch in the pipe before you
start to drill.
The drill tends to wander on SS, esp. on a convex surface.
I don't think you will need practice, pretty straightforward.
Just lots of coolant. I find WD40 OK for this.