Poll: Swage vs Compression for Rigging

[Alton]

just doing some research before i rerigg my boat.

[Wotname]

By compression I am assuming you are referring to Sta Loks and Norserman type fitting.

If so, they are what I used as they suited my purposes better, not because they are necessarily better (although I believe they are).

[mesquaukee]

Norseman and Sta Loks can be reused (need a new collar). They also can be sealed to keep saltwater and salt out.
Compression fittings cannot be sealed, saltwater gets in, water evaporates, salt builds up, etc. The metal is distorted from the forming process with changes the surface potential which encourages corrosion. Eventually they will fail due to crevice corrosion (5-10 years in the tropics).
By constrast with compression fittings the end of the wire can be cut should you suspect a problem and the fitting reused. Just add a shackle to compensate for the length.

[s/v Jedi]

My choice isn't there because we use swage at the top and Norseman at the bottom. The top fittings are upside down so water can't run in and stand there.

ciao!
Nick.

[Wotname]

OK guys, please enlighten me. What exactly is a compression fitting in your part of the world?

I KNOW what a swage is, but I am only guessing what you mean by compression fitting; Sta Lok, Norseman, Nicopress and rolled swages requires compression of metal at some point in the fitting so what is the common understanding as to what constitutes a compression fitting?

[mesquaukee]

A compression fitting is a field assembled fitting where the "compression" of the wire is accomplished by a turning a nut which compresses a tapered collar into the wire.
No special tools are required.

[Wotname]

Originally Posted by mesquaukee

A compression fitting is a field assembled fitting where the "compression" of the wire is accomplished by a turning a nut which compresses a tapered collar into the wire.
No special tools are required.

OK that's the way I understood it too.

Originally Posted by mesquaukee

Norseman and Sta Loks can be reused (need a new collar). They also can be sealed to keep saltwater and salt out.
Compression fittings cannot be sealed, saltwater gets in, water evaporates, salt builds up, etc. The metal is distorted from the forming process with changes the surface potential which encourages corrosion. Eventually they will fail due to crevice corrosion (5-10 years in the tropics).
By constrast with compression fittings the end of the wire can be cut should you suspect a problem and the fitting reused. Just add a shackle to compensate for the length.

So I think you meant to say SWAGE fittings cannot be sealed etc.

[mesquaukee]

So I think you meant to say SWAGE fittings cannot be sealed etc.[/QUOTE]

Oops, made a mistake. I meant to say SWAGE! Thanks.

[s/v Jedi]

This puzzles me because every decent rigger will seal every swage fitting by putting sealant in, followed by the wire and swage it like that. So, they are sealed, but you can't clean and re-seal them like you can for a Norseman.

ciao!
Nick.

[S/V New Sensation]

I picked swage because most of my rigging is swaged but I also have compression fittings

[osirissail]

- - Having been a rigger for a dozen years or more the best option is as mentioned - swags at the top and Staylok or Norseman at the bottom. But - (there is always a but somewhere) Swag fitting require special very large and very expensive equipment to do correctly. There are plenty of these machines around but cost of operating them is quite high. As a result it is less expensive to use Staylok or Norseman type fittings at both the top and bottom.
- - For rod rigging you have only one choice and the same for ball/socket terminals. They are swagged onto the wire or rod.
- - Only for classical rigging is there the option of swag versus Staylok / Norseman type terminals.
- - With Staylok there is also the option to go with the British "Dyform" wire instead of classical 1x19 wire. Dyform only comes in 316 stainless whereas classical 1x19 can come in 308 or 316 and most suppliers stock only the cheaper 308 wire. Dyform is 25% stronger wire and has a nice smooth surface to it.
- - I suggest getting Brian Toss's books on rigging if you are going to D-I-Y. And his video tapes - they are great and will teach you how to inspect and tune your rig.

[S&S]

Originally Posted by osirissail

- -- - For rod rigging you have only one choice and the same for ball/socket terminals. They are swagged onto the wire or rod.

On our rods the end is flared to hold the ball- is that what you mean? I don't see any compression marks from squeezing the ball (like I see on a wire swage fitting)

[osirissail]

- - Yes, to make the ball on the end of the rod a powerfull machine must be used to "push" the metal to form the ball. Common house nails were formed this way many years ago. They put the "rod" into a die and used a sledge hammer to beat on the end until it thickened and flattened into the head of the nail.
- - The machine that does the end on rod rigging must operate such that overheating and fractures/stress lines do not occur that would facilitate the the "ball" breaking off.
- - A major problem with rod rigging is the constant grinding/friction between the end terminal on the rod and the "socket" in the mast. They should be inspected regularly to ensure that they are not getting too worn. Same thing with any clevis pin fitting, constant motion wears/grinds the "round hole" into an "oval" hole or the pin gets grooves worn into it reducing its thickness until finally the pin shears in half.