Author Topic: External Chainplate Bolt Length  (Read 2303 times)

  • Guest
External Chainplate Bolt Length
« on: August 12, 2012, 12:55:55 pm »
Hi all,

I have received my new external chainplates with the recessed bolt holes and need to install them. The flat-headed bolts that I ordered appear to be too short - they are 1 1/2" from flat top to the end (entire length). Regular bolts are measured from under the bolt head to the end of the threads, which is what I thought I was ordering.

Anyway, I believe they will be too short. Before I order some more I thought I would ask what others have used on their external plates on CSY 44s.

Will 2" work, or should I go with 2 ½"? I want to keep the protruding bolt end as short as I can to eliminate snagging once everything is tightened up.

Thanks and cheers,

  • Guest
External Chainplate Bolt Length
« Reply #1 on: September 17, 2012, 07:22:29 pm »

I did my external chainplates 7 years ago but have no recollection of what length the bolts were. We used flathead socket head bolts that are measured using the entire length top to bottom.
I recommend you drill the first hole in the side of the boat and measure. Just lay the cplate on the outside of the hull, line things up and drill the center hole.

Dave McCampbell
s/v Soggy Paws

  • Guest
External Chainplate Bolt Length
« Reply #2 on: December 08, 2012, 07:29:19 am »
I just got this by email...

I am replacing my chain plates on my 79 CSY WO. I last replaced them 10 years ago, duplicating the factory design. This time, I am going to move the chain plates to the outside of the hull, and use my 10 year old plates as backing plates.

Charley Danforth used this method and it looks good and he is happy and I am going to copy him. We will cut out the old stainless steel chainplate tabs that insert through the teak cap rail for the turnbuckles to fasten to, and fill the holes up with 5200 and cap the tab holes with teak.  

However, my new, outside, chain plates will be titanium. Chris Greimes, Allied Titanium, wants to know how long to make the bolts to go thru the new chain plates, thru the hull, and thru the old plates which are now backing plates. Charley’s best memory is 2 ½ inches. But he thinks if might have been 2 inches for the port forward chain plates where you have to access the inside through the forward portside shower locker. Do you have any memories that can help me?  The internet literature supports a bolt length of 2 ½ inches.
Thanks, and Happy Holidays, Steve Dixon, SV Lanakila in Hawaii

  • Guest
External Chainplate Bolt Length
« Reply #3 on: December 09, 2012, 07:47:39 pm »
Hi Steve,

Have you looked at my write up about replacing our chain plates twice on our website at:

I am pretty sure that the side of the hull at the location of the chain plates is not more than 1". So if you add that to the thickness of your new plates and the old plates you should get the total thickness of plates and hull. Then add thickness of washers and nuts plus about 1/2" and you will be about right.
If it were mine I would not leave the old chain plates inside. You might also think about counter sinking the bolt heads into the new plates and using flat head allen bolts for a cleaner nicer look.