I'm making a steel-post-and-stainless-cable railing for my deck. The posts are standard 1-1/2 inch pipe. The cable will be attached with swaged fittings at the end and corner posts, but will simply pass through holes in the intermediate posts. I want to keep water from getting inside the posts where the cable passes through, so I plan to drill through the posts, and insert a short stainless tube across the dimeter of the pipe. I've experimented with both brazing and soft soldering the stainless tube in, and both appear to work, but the soldering is much easier. Also, the heat needed for brazing tends to melt the end of the stainless tube (5/16 OD, 1/4 ID), so the soldered job looks better, too. The posts will be painted.
So here are the questions:
- Will the soft soldered joint take normal outdoor Nebraska thermal cycles (-20 F to 105 F) without cracking over time and allowing rust to get a foothold? There is no real mechanical stress to the joint other than from temperature changes.
- Are there soft solders that are stronger than those for plumbing?
- Should I consider something else, like hard solder (I think this takes a temp as high as brass brazing, doesn't it?) or epoxy?