Mooring strops with stainless thimbles

[chris-s]

I usually make up new strops each year, but this year my son got one of the deckies onboard the boat he works on to make some up for me, they look great but they have used stainless thimbles and I’m not sure if that would be a problem or not.

The strops connect to steel shackles at the top of the riser chain below the surface.

They’ll be fitted for about six months till the end of the season and renewed again next year.

Is galvanic corrosion likely to be an issue? It’s a simple job to re-do them with galvanised thimbles.

 

[Farmer Piles]

In my experience, YES, majorly. I had a strop made up locally and assured that it would be fine with a stainless eye. All the top end of the mooring chain was eaten away as though it had been in an acid bath. The further down you went, the better the chain. The shackle pins were eaten out around the threads as well as being very thin. The only thing keeping the shackle pins in place were the cable ties that I used as belt and braces. All this in a matter of a few months.
Up to you, but I wouldn't use them. After my experience I eased the stainless eyes out of the strop and fitted galvanized ones.
Now I used 2 tonne nylon lifting strops. Tough, strong, kind on the boat and reinforced against wear around the loops.

Example below but you can get them from all sorts of places like Screwfix, etc... You could go for 3t ones if you want - yellow in colour. I have a 6t mobo on mine and they show no signs of wear by the end of the season but they are so cheap that I change then every year. At 2t, the deck cleats will rip out before they break.

Duplex Web Sling 2 Ton 2 Metre (2T 2M 60MM Green Strap Hoist Lifting 2000KG)

Hope that this helps.

Regards,

Matt

 

[chris-s]

In my experience, YES, majorly. I had a strop made up locally and assured that it would be fine with a stainless eye. All the top end of the mooring chain was eaten away as though it had been in an acid bath. The further down you went, the better the chain. The shackle pins were eaten out around the threads as well as being very thin. The only thing keeping the shackle pins in place were the cable ties that I used as belt and braces. All this in a matter of a few months.
Up to you, but I wouldn't use them. After my experience I eased the stainless eyes out of the strop and fitted galvanized ones.
Now I used 2 tonne nylon lifting strops. Tough, strong, kind on the boat and reinforced against wear around the loops.

Example below but you can get them from all sorts of places like Screwfix, etc... You could go for 3t ones if you want - yellow in colour. I have a 6t mobo on mine and they show no signs of wear by the end of the season but they are so cheap that I change then every year. At 2t, the deck cleats will rip out before they break.

Duplex Web Sling 2 Ton 2 Metre (2T 2M 60MM Green Strap Hoist Lifting 2000KG)

Hope that this helps.

Regards,

Matt

Sounds much like I expected. I’ll swap them out.

Thanks for confirming my suspicions.

 

[Rappey]

I've also experienced how bad a stainless shackle can be with a steel chain.

 

[Refueler]

If continuously submerged as in a mooring - then the dissimilar metals is a bad match.

But if the items are only occasionally water bound - then its usually not an issue ... my bower anchor is attached by stainless shackle to normal galv chain ...

That Plough has had that connection all through the 25yrs I've had the boat ... yes the chain end shows rust - but its surface and the main 'meat' of the chain is fine.

My point is - mooring strops - no - go for galv or black iron. Obviously inspection at intervals ...

If its only occasional use - then it can be used - but keep an eye on it ...

 

[MontyMariner]

The strops connect to steel shackles at the top of the riser chain below the surface.

Do away with the points of failure, cow hitch an eye spliced strop straight onto the ring on the riser chain buoy.