Hammerlock

[amanphoto]

I going to use a grade 100 yellow painted hammerlock to connect my chain to the anchor. It's rated at 5300 #. My question is do I need to secure the pin with anything? You have to drive the pin on with a hammer. How will this hold up in fresh water. It's not galvanized or stainless.

[Dhillen]

You are free to do what you wish with your boat but since you posted your plans here I hope you do not mind comment from those who may disagree with this idea.

A galvanized shackle attaching your chain to your anchor is a seamanlike solution and what is most used and most recommended. Some prefer anchor swivels but I do not like what torquing and shearing loads can do to them and what those loads will do to a hammerlock.

Your ungalvanized hammerlock will begin to rust quite soon even in fresh water and you have no way of securing the pin other than hammering it in and hoping that it will stay of its own accord. This is not good.

Stainless if fine for shackles as well on anchors as long as they are not used on moorings as stainless loses its "stain less" properties if not exposed to oxygen. The short time the hook is buried on the bottom will not cause undue rust on the shackle.

Galvanized shackles are cheaper than stainless and both are better than some handyman solution which will only bring you grief. If you value your boat do it the right way and get a proper shackle that you can seize mechanically with seizing wire.

Cheers.

Dhillen

[amanphoto]

This is what I am using.

[JonJo]

I'm glad you posted the image, otherwise I (for one) would have had no idea about what you were talking.

Your defining the WLL is not much use, by itself, what chain are you using - is it compatible.

I believe the pin is fairly secure once you hammer it in - but its secure for 'lifting' not the rigours of an attachment to a chain on the seabed. 'We' mouse or shackle pins because they 'shake' out, lifting shackles do not need moused (because they do not shake).

The problem will be the securing pin, it will corrode, be subject to abrasion (sand and silt in the seabed) which will continually expose fresh surface for corrosion. The securing pin is very 'thin' there is not much to corrode in the first place (and one ought discard a chain when it has lost 10% of the 'wire' diameter). I'm guessing, once corroded it might be difficult to knock the pin out? If you change the pin frequently it will not be an issue (but the rest of the device will also corrode) - the paint is decorative rather than protective.

I will be interested in how it performs, but would not want to conduct the experiment (on our own yacht).

But why are you rejecting the norm, a shackle?

Jonathan

[amanphoto]

Originally Posted by JonJo

But why are you rejecting the norm, a shackle?

Jonathan

The working load on this is much higher then a shackle. Shackles have that little bit that sticks out and gets snagged on stuff (like the roller my anchor is stowed on).

My chain is 1/4" G4 galvanized chain and a 1/2" 8 plait nylon rope.

[JonJo]

Originally Posted by amanphoto

The working load on this is much higher then a shackle. Shackles have that little bit that sticks out and gets snagged on stuff (like the roller my anchor is stowed on).

My chain is 1/4" G4 galvanized chain and a 1/2" 8 plait nylon rope.

Your thought process is identical to mine and I have come to the same conclusion - that what you call a 'hammerlock' merits investigation.

I have seen large galvanised (HDG) Hammerlocks (I'm guessing 1/2 inch) used in marine applications - so you are close - but I have not seen small ones - so you are not yet close enough! One, painted, that will fit a 1/4 inch chain will corrode quicker than you can blink your eyes. I tried a painted chain hook in very shallow water, so it was on the seabed all the time, and the paint wore off overnight. The pin on the hammerlock is both critical and thin but hidden - so you are not going to see corrosion and its an HT pin with other, potential, issues (that I am surprised no one has posted about yet).

Can you tell me - who makes the hammerlock you are looking at using and what size is it?

I'm going to check small, 6mm and 8mm (or 1/4 inch and 5/16th inch) WLL of 3,100lb and 5,700lb, hammerlocks, suitably treated for the marine environment, in the very near future but I'm not expecting results until the back end of the summer.

Jonathan

[amanphoto]

I got mine from...

Westech Rigging Supply | Logging Supplies | Rigging Hardware | Fall Protection & Safety...Premium Gear for Professionals!

I ordered 5/16th and it just fit with my 1/4" chain.

[delmarrey]

How are you going to get it off once it quits swiveling and rusts up? A grinding disk I suppose, which will send little bits of rust all over your deck and hull.

Whats wrong with a conventional galvanized shackle? And yes, do wire tie the pin on the shackle!

[IslandHopper]

I have used these before with no problems, just a pain to change out if you need to change anchors in a hurry.....

Hammerlock Link

[nigel1]

Judging by the colour, it will be manufactured by Gunnebo, its a company quite well known for chain and chain accessories.
Yep, usual way to change them out is by using a grinding disc, but you can make up a small jig to support the link which allows a hammer and punch to be used with good effect, but not on the deck of a small boat.

Gunnebo Industries - Start

[JonJo]

And for Americans - if you want to buy imported units then you could also try Pewag or Rud but for domestic supply you cannot go past either Campbell nor Peerless who also offer these same units.

Jonathan

[DoubleWhisky]

Doesn't Crosby make similar joints in galvanised steel?

[JonJo]

Double Whisky - you are correct, Crosby do make similar components - but whether they galvanise them, I could not define.

Jonathan

[nigel1]

Crosby hinge links go under the name of Lok-a-Loy, but I dont think they are galvanised.
In any case, I doubt if the pin could be galvanised.

[Dockhead]

You could also use a Wichard stainless socket-headed shackle. I use one of these:

Allen head pin bow

You have to Loctite the pin. Some people drill them for a mousing wire.

They run smoothly through any bow roller and will match a G40 chain for working load and UTS.