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wingover · 23-07-2010, 21:00

Hi,

Wondering what shackle I can use on a 3/8" HT chain? the working load of the chain is 5400 Lbs but a shackle that fits only have around 3000 Lbs.

I don't want a stainless one. are there any shackles with a smaller pin size that will fit a 3/8" chain but have higher working load.

craigsmith · 23-07-2010, 21:50

One assumes by HT you mean high test i.e. G40. Best to say so cos HT really means high tensile which is not what you have.

You need to compare break loads because American chain tends to play games with the WLL:break ratio, particularly with "high test". The break of 3/8" Peerless G40 is 16200 lb.

You'll fit a shackle with a 1/2" pin. A high quality Crosby* screw-pin shackle is nominally sized at 7/16" and has a WLL of 1.5 t = 3300 lb but a ratio of 1:6 to break = 19800 lb break.

You can get stronger shackles again, e.g. Crosby do a forged alloy version, but you can see the basic problem of comparing apples to oranges.

* No affiliation with Crosby, go with any reputable brand that provides tested shackles. Proof testing is important. Shackles are cheap, no excuse to have poor quality ones.

Mirar · 23-07-2010, 21:53

Hello, I just went through the same dilemma and found high test shackles from www.1st-chainsupply.com . The ones for 3/8 chain have a 7/16 pin that fit fine and are rated for about 2.5 tons. I think they are around twelve to fourteen dollars. Great service from these people by the way, with no connection to me.
cheers, greg

s/v 'Faith' · 23-07-2010, 22:37

I agree with Craig, Crosby is a good shackle.

Beware, many places try to pass off chineese shackles. They look fine on the outside, and some may well be. Others have failed and cost Sailors their ships.

craigsmith · 23-07-2010, 22:48

Where in the world a piece of steel is forged or cast is really unimportant. What matters is the reputation of the brand in question and how reliable its test certification is. The generic junk sold in bins in chandleries with no trustworthy ratings should be avoided even if it was made just down the street.

**GordMay** · 24-07-2010, 05:32

Quote:

Originally Posted by s/v 'Faith'

I agree with Craig, Crosby is a good shackle.
Beware, many places try to pass off chineese shackles. They look fine on the outside, and some may well be. Others have failed and cost Sailors their ships.

Indeed, the genuine article are great, but see the http://www.cruisersforum.com/forums/...les-43924.html

And ➥ http://www.thecrosbygroup.com/2002ed...3_Shackles.pdf

**Dockhead** · 24-07-2010, 06:39

Quote:

Originally Posted by wingover

Hi,

Wondering what shackle I can use on a 3/8" HT chain? the working load of the chain is 5400 Lbs but a shackle that fits only have around 3000 Lbs.

I don't want a stainless one. are there any shackles with a smaller pin size that will fit a 3/8" chain but have higher working load.

You'll find it easier to match the shackle working load to the chain if you have an enlarged end link made for your chain (and welded on before the chain is galvanized).

We've just been through this ourselves. The chain supplier threw in a nice shackle -- a Green Pin thing which matches the safe working load of the 12mm G40 chain we bought.

http://www.vanbeest.nl/home

Now we'll see if Craig's 55kg anchor fits our bow roller. Distribution of anchors in the UK is absolutely terrible. Manson doesn't distribute at all (that would have been our first choice); Spade are not stocked anywhere; of modern anchors only Rocna are kept more or less regularly in stock. But dealers have been waiting all year for 40kg Rocnas, and the others are in stock only sporadically. Sorry for the thread drift.

**GordMay** · 24-07-2010, 07:05

Quote:

Originally Posted by Dockhead

You'll find it easier to match the shackle working load to the chain if you have an enlarged end link made for your chain (and welded on before the chain is galvanized)...

Check out Crosby G-209-A Alloy Shackles
➥ http://www.thecrosbygroup.com/html/en-US/pdf/pgs/66.pdf

**Dockhead** · 24-07-2010, 07:15

Quote:

Originally Posted by GordMay

Check out Crosby G-209-A Alloy Shackles
➥ http://www.thecrosbygroup.com/html/en-US/pdf/pgs/66.pdf

Those look nice!

wingover · 24-07-2010, 08:06

Thank you all for your help.

Craig, I actually got a rocna 55KG and a new (US Made) 3/8" high test hot dip galvanized chain. I will loook at the crosby.

A side question about the rocna I got... The boat next to me has this stamping (done in the casting or by welder) under the anchor that says "genuine rocna 33kg". Mine doesn't. any idea why?

Thanks.

**Dockhead** · 24-07-2010, 08:21

Quote:

Originally Posted by wingover

Thank you all for your help.

Craig, I actually got a rocna 55KG and a new (US Made) 3/8" high test hot dip galvanized chain. I will loook at the crosby.

A side question about the rocna I got... The boat next to me has this stamping (done in the casting or by welder) under the anchor that says "genuine rocna 33kg". Mine doesn't. any idea why?

Thanks.

Hey, I ordered the same anchor as you have, which should arrive soon. I'm curious how it fits on your bow roller -- what kind of boat do you have? It looks humongous in the catalogue and I'm a bit nervous it will not work on my 54 foot boat. Although if it will, it will be great to have such an oversized hook.

And is your 3/8" chain G80? Or just G40?

CAELESTIS · 24-07-2010, 09:05

Dockhead, Rocna has actual size templates that can be printed. You can also look at the "knowledge base" section of their website, then go to the "bow compatibility" section.

Rocna Anchors - Home of the Rocna anchor - New generation boat anchors

craigsmith · 24-07-2010, 09:10

Quote:

Originally Posted by wingover

A side question about the rocna I got... The boat next to me has this stamping (done in the casting or by welder) under the anchor that says "genuine rocna 33kg". Mine doesn't. any idea why?

Your anchor is fabricated, the embossing is done in the castings. What you should have is the black aluminium labels with the Rocna logo on the sides of the shank.

P.S. just for the record, we advise 7/16" G40 for the Rocna 55, 3/8" if G70.
www.rocna.com/kb/Chain
www.rocna.com/kb/Shackles

Bash · 24-07-2010, 09:26

Quote:

Originally Posted by Dockhead

It looks humongous in the catalogue and I'm a bit nervous it will not work on my 54 foot boat. Although if it will, it will be great to have such an oversized hook.

They only look humongous when you first put them on the boat. After about a month, they shrink.