Glueing stainless steel tubing??

[jhulmer]

Originally Posted by a64pilot

If you chose to drill SS, use a slow speed, but lots of pressure and a lubricant. Beeswax is perfect. Thing is SS easily work hardens, and then it IS tough to drill through, so that is why slow speed and high pressure, the lube is more to keep the temp down, temp seems to be what work hardens it. If you drill it fast and it turns blue, then you are in for a treat

Excellent advice! we do a lot of stainless work and as soon as it gets hot you're screwed. The higher the nickel content the worse it gets. So 316L is harder to drill then 304L if you let it get hot.

Drilling slow with high pressure as a64pilot so perfectly describes, will prevent rubbing of the bit and promote cutting. If you let up the pressure stop the drill or it will heat up and you're screwed.

We use cutting oil and lots of it, but water works well and even spit in a pinch because if it gets hot you're screwed. Keep the bit sharp. The bit will tell you when you are about to get screwed, it will squeal. Add more pressure and coolant or sharpen the drill.

Sometimes it is better to start with a smaller bit and work up in size to prevent overheating.

So, if you get screwed and the bit continues to squeal after sharpening then you have a few choices, drill in a new location, try drilling the hole with a smaller bit, get a carbide bit and give it a try (expensive and brittle but usually works), or if able, drill from the backside through.

Tapping usually goes well because it is slow and doesn’t heat up too much. Use a sharp High-speed steel tap (not a job for cheap high carbon taps), Lots of oil, and go slow.

hope this helps

[Terra Nova]

There is good reason that quality stainless work is virtually all tig welded, not screwed, riveted or glued.

[Cadence]

Originally Posted by charliehows

well I've never actually done a welding course so I guess it doesnt require a tremendous amount of skill - i'd say $25 of practice sticks and a bit of scrap s/s would get you started.
for a bit of alliterative fun I'd say polishin' and passivatin' is for pussies...

My guess would be an inert gas wire feed welder would be far more successful for a clean bead on something as thin as SS tubing.

[cyan]

My first choice would also be TIG welding. My moderate TIG skills would probably require that this work is done OFF the boat, as tubing is tricky- providing every conceivable angle of difficulty. Stainless steel is WAY easier than aluminum IMO, as the heat won't dissipate so quickly. (IE the sweet spot between burning through the tube and not enough heat is easier to hit)

If you insist on set screws...
One set-screw trick used on Speed Rail (Hollywood's tinker toys) is to toss away those short ones and purchase longer versions that will reach THROUGH to the opposite inside of the tube being clamped by the screw. This is very similar to an earlier suggestion, but involves simply drilling one hole (where the original set-dimple mark is) just large enough to allow the (new, longer) screw to pass through (untapped), and continue on to pinch the same tube, but from the inside-out. If this ever gets loose, the joint won't actually SLIP out- it will just wobble. (at least until until the LONGER screw can wiggle WAY out, an inch or more)