stanchon re bedding

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crieders

Its been a while since I had to do one. Can someone give me the link? The one I have to do is the one opposite the frig where the vent comes out. Thanks
Cliff Rieders, c34 tall rig, 1990, hull #1022

crieders

www.sailingworld.com/vigorsta.htm   no longer works.
Any idea where good articles exist? Do we have any?
Any idea of bolt size or screw driver slot size with respect to stanchons.
I took a good look and noticed 12 inches of height to work with and one of the bolts sits atop a wood divider and is impossible to get a tool around.  Any ideas?
Cliff Rieders, c34 tall rig, 1990, hull #1022

mainesail

#2
Bedding Hardware With Butyl Tape
Re-Bedding Deck Hardware With Butyl Tape

Sealing The Deck Core To Prevent Rot
Sealing The Deck Core To Prevent Core Rot

Bed-It Butyl Tape
-Maine Sail
Casco Bay, ME
Boat - CS-36T

https://marinehowto.com/

Stu Jackson

Quote from: crieders on December 14, 2010, 12:30:57 PM
www.sailingworld.com/vigorsta.htm   no longer works.
Any idea where good articles exist? Do we have any?
Any idea of bolt size or screw driver slot size with respect to stanchons.
I took a good look and noticed 12 inches of height to work with and one of the bolts sits atop a wood divider and is impossible to get a tool around.  Any ideas?

Cliff, I just did a search on "stanchion rebed" and got a lot of hits with good information.  Please try that.

Take one bolt out and you'll know for sure.

Knock the wood divider out and reinstall it with glue.  I think Lance Jones wrote this up recently.  http://c34.org/bbs/index.php/topic,5840.0.html

You have to spell stanchion correctly or the search won't work.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Ron Hill

#4
Cliff : This has been written up more than once.
 
I believe the bolts are #3 Phillips head 1/4" x 20 .  You need a saws all (reciperating saw) to cut out the plywood section so you can get an boxend wrench on the underside nuts.
Then after removal of the stanchion, I recommend let the center hole dry out, filled that hole with epoxy and redrilled for the "vented base" of that stanchion to fit back in.  That stanchion might well be bent (inward) so straighten out ht e base to the top.  Make youself a backing plate out of 1/4" stainless.  
 
I'm now using 3M4200 as a sealant.  Purchase a square shank #3 Phillips (cross point) screwdriver.  Bed in the stanchion base, but only tighten the 4 bolts to about 3/4 tightness.  Make sure that the person holding the bolt has the screw driver in the head slots while holding a cressant wrench on the screwdriver shank  - to keep the shank & bolts (and caulk) from turning.  Let the stanchion sit until the the caulk has almost completely cured.  Then crank down the nuts again keeping the bolts from turning.
Ron, Apache #788

mainesail

#5
Quote from: Ron Hill on December 14, 2010, 06:49:06 PM

 
Bed in the stanchion base, but only tighten the 4 bolts to about 3/4 tightness.  Make sure that the person holding the bolt has the screw driver in the head slots while holding a cressant wrench on the screwdriver shank  - to keep the shank & bolts (and caulk) from turning.  Let the stanchion sit until the the caulk has almost completely cured.  Then crank down the nuts again keeping the bolts from turning.

You guys can do what you want on your boats but using the Don Casey "tighten twice" method is the last bedding method I would use on even my worst enemies boat. But that's me... Don Casey has given some good advice over the years but this is not in that category IME. As far as I am concerned it is good advice, to keep boat yards in business repairing wet decks. :D

When I worked with my buddy Brian surveying boats there were two types of boats that we knew we would find moisture in. DIY re-beds using the Don Casey method and Pearson's and other boats with the gaskets under the stanchions.

One boat we surveyed was a Catalina 30 from about 1982. When we surveyed it she had moisture intrusion at about 50% of the stanchions, the push pit, chain plates, bow pulpit and misc deck fittings etc.. Only about 10% of the areas "pegged" the meter or showed soundings of delam. The moisture was well mapped via moisture meter and soundings for repair. The new owner had the yard repair the really bad & critical areas and then he re-bedded the rest of the boat using the Don Casey method.

The repairing yard beveled and tightened once the areas they repaired. The owner used the Casey method. When he went to sell the boat he was horror struck at what we found just four years later. Wet decks MUCH worse than what had been there four years earlier EXCEPT for the items re-bedded by the boat yard. All of his stanchion feet that he had bedded were now pegging the meter and because he let it cure to long and could not fully compress the polyurethane the stanchions exhibited significant movement when flexed. If this was the fist time we had seen this it would have been one thing but sadly it is and was not the first time...

Hinckley, Morris, Alden, J Boat and many other quality builders have known for years how to properly bed an that has always included a slight beveling/countersinking of the deck and a tighten once approach. The production builders find it too costly to take an extra 30 seconds to bed the deck hardware in a manner that can almost guarantee dry decks for many, many, many years.

I was taking pictures of my buddy at Morris one day while he beveled the holes for a Dorade vent on a new M-36 bound for Down Under. It took him under 50 seconds to do all four holes and that included finding a fresh battery for his drill.


Our brand new 2005 Catalina was 100% re-bedded over the 2006 winter due to numerous deck leaks and I no longer trusted any of it. This is ridiculous on a brand new boat but simply comes down to poor factory bedding technique namely no countersunk holes. On the other hand my CS-36 has 80% of its deck hardware un-rebedded and in 32 years and no leaks, not even the chain plates but CS used butyl.

Since I began beveling, learned it at Hinckley in 1987, I have never had a fitting re-leak. I have also had a moisture meter on numerous boats, well into the hundreds, and have had the opportunity to compare builders that bevel the deck fitting holes and ones who don't. The leak and wet deck rate is in the realm of 90% less on builders who bevel than on boats that do not bevel.  

The Don Casey method is not the absolute worst but darn close to it because most DIY's can't get the process of cure, tighten, re-tighten just right. The gaskets Pearson used have about a 90-95% failure rate and I would consider those the worst possible error made in the boat building industry.

Here's one example why. This was from a Pearson 34 I surveyed. An improperly done Casey method, allowed to dry/cure too long, and wrong thickness can mimic this and lead to a similar wet core reading.

http://www.youtube.com/watch?v=ga0eeZ6ZhIY

These lifting eyes were installed by me 8 years ago now. I used 3M 101 polysulfide and the countersink tighten once method. They reside BELOW the waterline and are used to lift this RIB into the davits when we do that. They are, and have been bone dry for eight years, while being 100% submerged bellow water. Slight bevel, apply sealant, tighten, clean up and done. :D

Proof is in the "submerged" pudding: :thumb:







-Maine Sail
Casco Bay, ME
Boat - CS-36T

https://marinehowto.com/

Roc

Maine Sail,
Just to get it straight, what you do is bevel the hole, so a pool of caulk resides against the shank of the bolt passing through.  Then you tighten once, where the hardware comes right up against the fiberglass.  The picture you post of the Dorade vent hole is hard to see the bevel because of the glass shavings.

I like this procedure because I have found, in the re-tighten method, it is very hard not to let the bolt turn during the second tightening step.  If it turns, you now lost the seal between the caulk and bolt.
Roc - "Sea Life" 2000 MKII #1477.  Annapolis, MD

mainesail

Quote from: Roc on December 15, 2010, 04:23:53 AM
Maine Sail,
Just to get it straight, what you do is bevel the hole, so a pool of caulk resides against the shank of the bolt passing through.  Then you tighten once, where the hardware comes right up against the fiberglass.  The picture you post of the Dorade vent hole is hard to see the bevel because of the glass shavings.

I like this procedure because I have found, in the re-tighten method, it is very hard not to let the bolt turn during the second tightening step.  If it turns, you now lost the seal between the caulk and bolt.

Yes you are in a sense creating a thicker layer of caulk/o-ring that will not allow the hardware to move but if it does you sill have a lot of sealant thickness. 500% elongation of 1/16" or 1/8" is a LOT more allowabe flex before failure than 1/64"..
-Maine Sail
Casco Bay, ME
Boat - CS-36T

https://marinehowto.com/

Ron Hill

Just goes to show you that we all learn something from these posts!!

Here I thought I was using the "Ron Hill" bedding method for the past 30+ years.  Wonder if Don Casey read one of my articles? (smile!)

Seriously, I like the beveling idea.  Also I've used the black butyl rubber before (years ago) as a roof patching material, but didn't know it by that name.  I've since bought some of R.C.s gray butyl rubber and plan on using it on any future leaks.

I still profess that the hole (now beveled) should be just large enough to push the bolt thru, but held from turning while the bottom nut is tightened.  This insures that the seal is thru all of the threads and the beveled area.

As Mainsail mentioned there were some great caulks on the old market that just went away.  I used to use one marketed by RULE which was a "elastomeric caulk".  Great stuff, but no longer there.

I thank Mainsail (R.C.) for bringing some of his experience to our message board!!   :thumb:

Ron, Apache #788