using a square u-bolt for a stern dock line chock

gkny

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I had a cast aluminum chock that was integrated with the toe-rail that broke.  It was a closed D shaped loop.  I have looked for another but not found a matching one.  I am thinking about using a square stainless u-bolt for the chock.  I would like the line to be protected whether it is running forward of the cleat or aft of the cleat and the skene or angled chocks seem to work only in one direction.  If I use a large diameter u-bolt (say 3/8") is that a large enough diameter to protect the line?

 

slug zitski

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I had a cast aluminum chock that was integrated with the toe-rail that broke.  It was a closed D shaped loop.  I have looked for another but not found a matching one.  I am thinking about using a square stainless u-bolt for the chock.  I would like the line to be protected whether it is running forward of the cleat or aft of the cleat and the skene or angled chocks seem to work only in one direction.  If I use a large diameter u-bolt (say 3/8") is that a large enough diameter to protect the line?
Stainless U bolts make poor chocks 

2DB2E6BF-40C3-4EB8-B2DE-200E564B9B97.png

 

Zonker

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You want roughly the radius = line diameter. So a 3/8" diameter rod = 3/16" radius. i.e. a bit too much point loading unless you are tying up a dinghy with 1/4" rope. I would try to get a closed chock. 

It's entirely possible your existing closed chock had a fairly tight radius as well. Have a look. Just measure the thickness and see if it will be close to your 3/8" U bolt.

 

Gouvernail

Lottsa people don’t know I’m famous
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Maybe I skimmed too fast but.. what kind of biat snd what year was it built… and the photo of the other side gets you hundreds of additional assistant search eyes. 
  It is all about “fixit thread cred” 
   You can bet your sweet bippy every one of us would like to be the first one to tell you where to get one. 

 

El Borracho

Sam’s friend
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Pacific Rim
FWIW - My dock lines run thru a square u-bolt at the bow. About 1/2”. Makes a 90° turn. Like wise ones @slug zitski & @Zonker said it is not recommended. The 5/8” line wears quicker that it should. $$$. Works for me though. I’m not supposed to be tied to a dock…COVID. 

 

gkny

Member
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26
The boat is an X-372 from the late 80's.  I have attached a picture of the port side.  The starboard side broke when the boat took a big roll from a large boat wake.  Any suggestions welcome.  thanks!

chock2.jpg

 

SloopJonB

Super Anarchist
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Did you try contacting X-Yachts?

If that's no go then Sluggo is right - find an alternate the right size and get two so they match side to side.

 

SloopJonB

Super Anarchist
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Exactly.

Of course I rebel at the thought of different style screw heads under grain oriented teak plugs.

 
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Zonker

Super Anarchist
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I have literally put up a small bracket with 3 different screw head styles. (Robertson / oval head and flat head Phillips). Have not managed all 4 quite yet.

It's wrong but sometimes I've been a long way from a marine store. I'm like a Cuban car mechanic. "Oh look. Here's a bolt. It will fit... Moving on"

 

Gouvernail

Lottsa people don’t know I’m famous
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Hell.. this thread is way too long. Make something out of duct tape, beer cans, and  seizing wire,  and  get on with your life

 
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