Chain Plates

[eherlihy]

Originally Posted by Semloh

I don't understand why you couldn't just put a nut on the u-bolt and tighten it up. It may not have flattened the block but it seems it would have been worth a try.

The problem was that the block was out of square with the U bolt - because only ONE nut was in place and had been tightened. Coupled with the fact that the nuts fit in recesses in the block, I was initially unable to put a nut on the other leg of the bolt.

Once I flared open the recess with a dremel, I could get a nut started, but was concerned that I would loose the nut if I tightened it into the block.

Also why did you drill out the bolt holes? It looks like the core was marine plywood and in good shape. Couldn't you have just rebed the existing holes?

Once the U bolt and top plate were removed, I could see that there was a depression in the deck. I had already detected moisture around this chain plate, but could not see the core because everything in there was covered with some kind of sealant (at least somebody had tried to rebed this plate at one time). I assumed the worst, and broke out the hole saw.

Actually, I believe that there was degraded marine ply. immediately around the holes. To see how I plan to address the holes in the deck, look here.

I agree that the exposed marine ply looks to be in good shape.

[eherlihy]

Originally Posted by RichH

Contact D & R Marine - drmarine.com - as they are *THE* source for O'day parts, etc. and may give you specific 'hints' of specifically how to 'easily' tighten/replace, etc.

I want to follow up on the above quote in the hope that someone can leverage my research.

I never heard back from Rudy, even after I called him about a week later to inquire if he had found a source. He had my number and remembered speaking with me, but never contacted me again. My impression is that D&R specializes in the O'days of under 25 feet overall.

I eventually stumbled on the RigRite website, as a source of chain plates and backer blocks. The O'day 34/35 uses NavTec U bolt type chainplates. Here is a pic

These are available in 3/8" and 1/2". Here is what the RigRite website says about them;

3/8" Navtec U-Bolt Chainplate Assembly: Nav UBA-6S-2:
Navtec 3/8" U-Bolt Chainplate Assembly bolts through Deck to special Tie-rod Block which accepts SS tie-rod at a specific angle. Formed, flattened SS U-Bolt has 3/8" thread with 1 5/8" between centers, and extends 2" below deck surface. Note that some units were produced extending only 1 3/4" below deck, these are no longer stocked. Assembly includes U-Bolt with SS Top and bottom plates, lock washers and nuts. As used on a variety of boats including Bristol, Cal, C&C, Ericson, O'Day, the Hobie 33, and others.

RigRite has part numbers on their site for the entire assembly, and the components.
... and;

1/2" Navtec U-Bolt Chainplate Assembly: Nav UBA-8S-2.5:
Navtec 1/2" U-Bolt Chainplate Assembly bolts through Deck to special Tie-rod Block which accepts SS tie-rod at a specific angle. Formed, flattened SS U-Bolt has 1/2" thread with 2 1/8" between centers, and extends 2 1/2" below deck surface. Note that some units were produced extending only 1" or 2" below deck, these are no longer stocked, but can be produced by cutting the longer ones, if necessary. Assembly includes U-Bolt with SS Top and bottom plates, lock washers and nuts. As used on a variety of boats including Bristol, Cal, C&C, Ericson, O'Day, Southern Cross, and others.

More info can be found here: U-Bolt Type Chainplates

Note: I have no interest in Rig Rite. I am only trying to help expedite someone else's search.

I have decided that the backing block pictured in my earlier post is "good enuf" and that the visible corrosion is cosmetic and not structural. Once the plate is rebedded correctly (if this cold weather ever ends) I believe that the block will be fine. Should I ever need it, Rigrite sells this block too;

3/8" U-Bolt Chainplate Tie-rod Block: Nav UB-6S-TRB-__:
Tie-rod Block for single 3/8" U-Bolt Chainplate. Anodized Aluminum Tie-rod Block is 2 9/16" long x 1 1/2" wide x 5/8" thick, with (2) recessed holes for nuts and washers, and a machined socket for 3/8" cold-headed tie-rod. Note: These items were produced with the socket machined for a wide variety of simple and compound tie-rod angles, please specify.