Mast tang service life

[GILow]

I can find very little written about the service life of mast tangs.

A little bit about inspecting them for cracks, rust etc, but not much else.

What do people think is a reasonable life span for properly constructed stainless steel tangs on a 44 foot cruising mono?

[Greatest Lakes]

Mast tangs themselves should be fairly immortal. They are designed to be stronger than the stays and shrouds, and they don't experience much movement. So long as there is no cracking, stretched holes, and the fasteners are well regulated, you should be in good shape.

[Bowdrie]

^ I agree, assuming they're not undersize the service life should approximate that of an anvil.
Personally, I prefer double tangs, (along with a toggle,) and an eye fitting rather than single tangs using a fork fitting.

[Cheechako]

Agree #3 ^^^

[GILow]

Ok, thank you all, I’ll relax a little then.

These are all from a reputable American spar builder. They do look seriously well made but I’ll dye-test them to be sure.

And Bowdrie, you’ll be happy to know they are all doubles with eye terminators.

I will replace the bolts though.

[Cheechako]

Originally Posted by GILow

Ok, thank you all, I’ll relax a little then.

These are all from a reputable American spar builder. They do look seriously well made but I’ll dye-test them to be sure.

And Bowdrie, you’ll be happy to know they are all doubles with eye terminators.

I will replace the bolts though.

Often the bolts through the mast are corroded into the mast. If you get them out, coat them liberally with something to avoid the aluminum/SS corrosion propensity.

[GILow]

Originally Posted by Cheechako

Often the bolts through the mast are corroded into the mast. If you get them out, coat them liberally with something to avoid the aluminum/SS corrosion propensity.

They were better than I expected, but yes, I’m thinking Tefgel. What do you reckon?

[Cheechako]

Originally Posted by GILow

They were better than I expected, but yes, I’m thinking Tegel. What do you reckon?

Tefgel or some other modern material would be good. I used to use Lanolin, it works but it will get crusty over time and heat. Clings very well though.

[Bowdrie]

Choice of anti-seize/anti-corrosion product is largely a personal choice influenced by prior experience.
Whether the bolts go thru the mast using doubler-plates or a welded in tube it's important that the bolts have freedom of rotation thru the holes/tube, and that the tangs have freedom of rotation on the bolt.
And that the bolt has ~1/16th" of lateral freedom.
All this allows changes in mast rake/bend, and shroud/stay tensions without creating "hard spots" of loading.
In some masts the eye of the uppers terminates between a pair of welded plates, in such cases a toggle should be fitted.