Attaching snubber to chain...

[tdw]

Originally Posted by Omatako

If by chain hooks you guys mean one of these, I have been using these for years to stop chain growl. Coincidentally bought this one the other day and still have to splice a line on.



I never use it to hold a rode that has not got the bitter end securely fastened to the boat but I have yet to have one of these jump off a chain and when on, it does no damage.

Oh, and I have no need for a bridle.

That's the one. Virtually exactly what we have. Ours has slightly different attachment point for the line.

[Cruisingdad]

Originally Posted by tdw

That's the one. Virtually exactly what we have. Ours has slightly different attachment point for the line.

Yep... the same one I use Fuzzy. Cheap, simple, cheap, cheap, etc. Did I tell you that I use that one because it is cheap? Why is this so important? Because it also does not float!!!

Brian

[tdw]

Found this.....looks interesting......simple to make.....think I'll try it out.



Of course the other alternative would be to simply use a big enough shackle and runs two lines from the hook itself. Same result, even simpler to make.

[Cruisingdad]

Originally Posted by tdw

Found this.....looks interesting......simple to make.....think I'll try it out.



Of course the other alternative would be to simply use a big enough shackle and runs two lines from the hook itself. Same result, even simpler to make.

That is basically what we did, except we have a true rubber snubber on the main line before the splice.

Brian

[tdw]

Originally Posted by Cruisingdad

That is basically what we did, except we have a true rubber snubber on the main line before the splice.

Brian

What is a 'true rubber snubber' ?

[Cruisingdad]

Originally Posted by tdw

What is a 'true rubber snubber' ?

This:

[IMG][/IMG]

[IMG][/IMG]

They do a great job at taking out the "bump" when the line get taunt. However, they can snap in a storm. THat is why you always want to make sure that if you use them for dock lines, that you have a secondary line to take up the slack should the snubber break. This is only an issue in the dock because if the dock line breaks, you suddenly have more slack in your dock line and you don't want the boat rubbing on the leward dock. The line itself is still there and will hold. Does that make sense??

Brian

[pdqaltair]

OK, first I found source for a commercial plate: ABI. It is 5/16" thick SS with no rated working load. Workable, similar to Sailingdog's plate, and I found some sailors with experience. One, with a 39" 12,000# Privilege cat is using one on a circumnavigation and is happy with it. He noted that it has distorted a bit, as the cat sails at anchor sometimes. I am sure he has used it hard.

Though I have worked with chain hooks, I have always wonder if they could come off, however seldom. A few sailors noted that yes, it has happened to them. Two noted that their hooks had released when their bridle touched bottom, which is not uncommon for a cat at slack tide. Perhaps a rock or the mud lifted it off - we do not know. Thus, I came up with this design, in red.

It is 3" x 4" x 3/8" plate, galvanized after fabrication, A-460 steel, as I recall. The calculated working load is 3200# (one leg attached, gate open) and I pulled it to 5500# (one leg attached, gate open) with no permanent distortion (I have a test rig, used to destroy rock climbing gear - my other passion). With both legs attached and the gate closed, the working load is ~ 10,000 pounds, but it does not matter because no other link in the system is so strong. I have since replaced the gate shown in the photograph with a thicker piece of 316 stainless, for better feel, durability, and strength in the gate, should there be some odd bind.

Some have commented on the longer slot and strength; yes, the arm is longer but the angle is less and the calculations show only minor differences. I did pull test it. With the gate in place it is MUCH stronger, just as a carabiner is 3x stronger closed with gate (thay are generally rated closed gate, but sometimes marked with open gate ratings as well). I sized it for my 8000# cat, so if you have something heavier, adjust accordingly. Also the carbon steel plate I used is tough but not exceptionally strong; there are better materials.

The hole at the bottom is for attaching fiber rode (rolling hitch) should I let out more line and run out of chain. If you have all chain, delete it.

Thoughts? My blog has another photo and additional discussion.

Perhaps it is mostly a catamaran thing. If I like it well enough - I have only used it twice - I may fabricated in 304 or 316 SS in the Fall. I suspect I will find 5/16" is then enough for my boat, and as strong as the other components in the system.

[St Anna]

We always used a hook, but the snubber used to make noise on the bow roller. Therefore We shackle onto the outside of the bow roller and this stops any noise and eliminates all chafe. It is easy to hook on as you lower the chain. Also about 5-7m for the snubber and leave a huge loop of chain. Works a treat.
David

[Keldee]

We always use line and attach it to the chain with a rolling hitch.So far never had a problem with chafe as we use a chafe guard made out of clear plastic piping held in place with electrical ties.Have anchored through a catagory 1 hurricane, a tropical storm and pretty sustained high winds in the bahamas.

[tdw]

Originally Posted by Cruisingdad

This:

[IMG][/IMG]

[IMG][/IMG]

They do a great job at taking out the "bump" when the line get taunt. However, they can snap in a storm. THat is why you always want to make sure that if you use them for dock lines, that you have a secondary line to take up the slack should the snubber break. This is only an issue in the dock because if the dock line breaks, you suddenly have more slack in your dock line and you don't want the boat rubbing on the leward dock. The line itself is still there and will hold. Does that make sense??

Brian

Ha, took me long enought to reply didn't it ? Sorry about that Chief.

I did know what a snubber was, it was the 'true' part that confused/bemused me.

I like the allowing for a safety line. Nice bit of design.