Water in keel joint

[DaveBMusik]

I've been following the mast step thread with interest. Although that is not my problem, it would be nice to know that there is no water between the hull and keel.
I purchased Water Music last spring and do not know much of the history.
I have had a weeping keelbolt all summer and have a small (1 to 2") brown stain on the port side of the keel. I can repair the "smile" but don't know if there is any water left between the keel and hull.
I'm not anxious to drop the keel.
Has anyone given any thought to drilling a hole in the bilge, sucking out any water, and then dumping a bunch of epoxy in the void?

[KWKloeber]

Dave

When I dropped and rebedded my keel, i learned a ton (naturally) and the boys at Gougeon brothers were EXTREMELY helpful. CTY, not so much.  The joint (bedding) is polyester (not epoxy) resin based, which is hydrophilic, and turns to mush given enough time.  How would you know where to drill (presuming you could suck out the water) -- it could travel thru tiny pores and pathways and attack a completely different location.   And the mush you'll never suck out.  Best you could do is vacuum dry the mush over an off season and hope for the best by replacing it with resin, but again no guarantee that it would get to all the mushed locations unless there were a 'map' of holes drilled and filled.  I found that nearly 1/3 my joint (bedding) had deteriorated (after 10 years.)  The other 2/3 that was good was a BEAR to get through.

-kk

[DaveBMusik]

Dave

When I dropped and rebedded my keel, i learned a ton (naturally) and the boys at Gougeon brothers were EXTREMELY helpful. CTY, not so much.  The joint (bedding) is polyester (not epoxy) resin based, which is hydrophilic, and turns to mush given enough time.  How would you know where to drill (presuming you could suck out the water) -- it could travel thru tiny pores and pathways and attack a completely different location.   And the mush you'll never suck out.  Best you could do is vacuum dry the mush over an off season and hope for the best by replacing it with resin, but again no guarantee that it would get to all the mushed locations unless there were a 'map' of holes drilled and filled.  I found that nearly 1/3 my joint (bedding) had deteriorated (after 10 years.)  The other 2/3 that was good was a BEAR to get through.

-kk

So, knowing what you know, with only a small "smile", would you repair that, seal the keel bolt and hope the corrosion of the keel bolts is minimal or drop the keel?

[tgsail1]

David- One more thing to keep in mind... IIRC, the 1986 models have a wood core in the bilge (I think they switched mid-'88 to all glass, someone please correct me if I'm wrong). If the bolts have been leaking, there is the possibility of rot in the core. If the core is rotten, no amount of torquing will fix the smile. You might consider a careful exploratory hole or two into the core to determine the condition. That might help in your decision making.

note: modified this to correct all-glass date to mid-'88 per
http://c34.org/bbs/index.php/topic,8132.0.html
Rick Allen wrote this up before

[Ekutney]

David,

I am very interested in what you find.  I bought my boat last year and had it hauled to replace the thru hulls with bronze sea cocks, there was no "smile" (the same was said when I had it hauled for the survey) and I was told by the yard there was no leaks at the keel joint.  I have a cabin stepped mast but still have a minimal amount of water in the bilge (still searching for the exact source).  I have reviewed all the material found on this site regarding the keel and am still trying to determine if tightening the keel bolts while the boat is in the water is a good idea.  Since my boat is an early '86 I am concerned of the condition of the wood core.

From everything I've read and from talking with the local yards, dropping the keel is NOT an easy task and there seems to be a variety of stories as to if the mast needs to be stepped.  One yard says, another says sometimes and a third says doesn't have to...  I will keep asking until I get more specifics.

[KWKloeber]

The yard I was in at the time I would not let me drop the keel unless I unstepped the mast (top heavy, I guess .)  So that I didn't need to depend on the yard (him lifting the hull) I literally unbolted and lifted the hull an inch at a time until the keel popped free.  I blocked it, and lifted the hull above the bolts using the cradle (and maybe a couple jackstand) screw jacks.  Super easy as pie. 

With the hull so the bolts could pass by, I hydraulically jacked the keel sideways (built a little 2x4 frame to hold it upright and "slide on" while jacking it over) to work on the mating surfaces.  More pie.  Working on everything, grinding down the mating surfaces and fixing was also pie.

The only really "HARD" part was getting the old (still good) bedding out before lifting the hull.  It's HARD AS NAILS.  Ended up drilling completely thru the joint (one side to the other) every couple inches with my long 1/4" electrician's bit, and using a carbide-tip reciprocating-saw blade to cut between drill holes.  That took forever.  Very SLOW going.

After the keel was back on, I built a structure of southern yellow pine (ie treated lumber) 4x4s to support the bow because I didn't want to rely on just bow stands, and I had to jockey supports around to take down the entire bottom, and so had to have access to the entire hull.  The yard owner poo-pooed it and said he'd lift the hull while I did the areas by the stands -- but I say no way -- he was THE most difficult person to work with.  It was not unusual for him be off cutting grass when there was a line up waiting to go in in the spring.  Mine worked LIKE A CHARM. 

-kk

[KWKloeber]

So, knowing what you know, with only a small "smile", would you repair that, seal the keel bolt and hope the corrosion of the keel bolts is minimal or drop the keel?

Dave,

I don't have a before pic, but my leak was "small" -- I noticed water stains on the keel from a very narrow crack -- not "hairline" but pretty small, about a foot long. 1/3 from ir so the trailing edge, not a CTY  :-) per se.

As I said, it ended up being 1/3 of the joint when I got it opened up.  Would I drop it again? -- dunno, maybe not at this age. LOL!  Understand I did all the work (w/ buddy only when necessary) so basically phone calls/faxes and materials is what it cost me.  Welder/fabricator buddy cut me two 1/8" s/s plates to spread the keel bolt load across the bilge (I floated in a flat epoxy base for them to sit on.)  I would defo do some things differently if I did it again -- like at the time I did not know about the C30 deteriorating wooden compression block  in the bilge (WOODEN and water!!!???!! For a structural member???), and the factory fix to remove the wood (WOOD and water???!!?? That's WORSE than an iron pump and water) in the keel buss (as I said -- assistance from GB was great? - CTY NOT so much, in fact that's part of my noticable bad taste for CTY's "engineering" and especially "service.") -- Notice I intentionally didn't say "customer service" -- just "service,"  The hosing kind of "service," (which I bent over and did receive.)  So those two are still buried in there -- I believe my C block is ok (so far.)

If I knew all that, I "wood" have done all three things -- But I was up against a trip 2 week scheduled, and a lot of work -- keel joint (rebed w/ 5200 per GB recommendation, torqued, biaxial-glassed and faired the joint, etc,) redid the entire bottom (down to gel, sprayed 7 coats VC tar and then VC-17,) fabbed epoxy bearing surface to permanently fix the rudder post slop, so...... 

I'm sure that, if I ground two inches in and glassed over and faired my joint per CTY's drawing, I'd still have lead hanging there.  If I just ground out some bad soft and 5200'd the joint, it would also still be hanging there today.  Would it be right?  No.  Would I have saved money and time -- YES!!!  But, I'm not sure what I would have done with the punky sections that were extensive w/o dropping the keel.   But I tend to go 120% to eliminate future issues -- sometimes that backfires though.  LOL.  Of course, I didn't know what I was getting into until I started ground away all the fairing -- then it became an info and learn-as-you-go, work=in -progress.

Do you have any pics?  As far as yours/specifics, I can't possibly say without at least seeing what's there having ground out some fairing and how extensive it is below that.  Also I don't know your situation -- fix 'er up as cheaply as possible -- or have the funds to go the full gamut? 

If I were doing it all myself, that's cheap labor AND I KNOW what's gone into the finished product (AND what' I've chosen to hide/ignore.  LOL.)

When you say fix the weeping bolt -- need much more info as Noah "alluded to."  HOW would you do that?  Mine was always (as far as I knew) leaking out -- with freeze/thaw acting on the punky joint for who knows how many years?   It would do nothing but get worse until I did something to stop that.  Now I KNOW there's nothing getting in -- but there may still be some wet wood in the keel buss (as I said that was before I knew about physically cutting that out and replacing w/ built-up glass.)  I'd at least drill some holes and see how wet  (or maybe rotted?) the wooden plank" is.

-ken

[DaveBMusik]

It's my understanding that this wood is not structural and was just used to assist in the layup. I still there any danger of leaving wet or rotted wood there?

[KWKloeber]

Not sure what you mean not structural.  If it's part of hanging the lead, is it structural?
Is it just taking up space, or part of the hole keel buss strength? 

Why lay up glass in its place if it's not "necessary"? 

Could you substitute Rice Crispies for the plank and sleep nights?

[tgsail1]

I can't resist a calculation challenge...Let's assume the core is totally rotten so there is empty space between the skins. Now lets assume each keel bolt is torqued to 105 ft-lb. Based on a previous calculation, the resulting tension on the bolt is of order 7000 lb. Now assume the bottom skin is snug against the keel. We can then assume all of the bolt tension is going into deflecting the top skin (as a point load for a one inch dia washer with about 8 inches across the stub). Found a formula for the deflection of an edge-bound round plate (www.roymech.co.uk), plugging in the modulus of fiberglass, an 8 inch diameter (the approximate edge of the bound area of glass), a 1 cm thick piece of fiberglass deflects 4 mm, almost half its thickness. If the glass is 1" thick, deflection is only 0.25 mm. So I guess the answer depends upon how thick the top skin is (Deflection gets smaller as the cube of the thickness). How thick is your skin?   

[Noah]

Substitute Rice Krispies? Wheat Chex has a much stronger structure. 

[Noah]

KEN, you mention GB Bros., inventors of WOOD/epoxy saturation technique WEST System and cold molded WOOD boat building, advice was helpful to you?  Note:They aren't afraid of wood in the bilge, as long as it is handled correctly.

[KWKloeber]

I think the below is a different situation -- which is one section of fglass that's being compressed at the top surface, not two pieces that's being drawn together, with potential mush in between them?  Or maybe I'm looking at it askew?

-k

I can't resist a calculation challenge...Let's assume the core is totally rotten so there is empty space between the skins. Now lets assume each keel bolt is torqued to 105 ft-lb. Based on a previous calculation, the resulting tension on the bolt is of order 7000 lb. Now assume the bottom skin is snug against the keel. We can then assume all of the bolt tension is going into deflecting the top skin (as a point load for a one inch dia washer with about 8 inches across the stub). Found a formula for the deflection of an edge-bound round plate (www.roymech.co.uk), plugging in the modulus of fiberglass, an 8 inch diameter (the approximate edge of the bound area of glass), a 1 cm thick piece of fiberglass deflects 4 mm, almost half its thickness. If the glass is 1" thick, deflection is only 0.25 mm. So I guess the answer depends upon how thick the top skin is (Deflection gets smaller as the cube of the thickness). How thick is your skin?   

[KWKloeber]

Good point - Agreed, "handled correctly!" - no disputing that - There's good ways to use wood and I have. 

But my protestation (!!??!!??!!) was for (wood??!??!) not specifically an epoxy-infused wooden block, which is essentially an "epoxy block" when once done.  Sure, I've coated and infused wood and used it cuz it's cheap and easily worked where I've needed to or it's convenient -- but it wasn't structural per-se and a key component that's hidden and not "replaceable" when it rots.

That said, why take the chance if you don't need to?  Expect the worst and plan/engineer/design for it -- there's better alternatives, as the CTY "fix" (or should I say "oops, we made a mistake however caveat emptor") demonstrates.  Why isn't CTY's fix to replace the plank with epoxy-infused balsa or marine ply or whatnot else?)  Maybe cellulose was just a bad design choice in the first place?  If it was a great idea, why drop it in later models, right?

JTSO

-ken

KEN, you mention GB Bros., inventors of WOOD/epoxy saturation technique WEST System and cold molded WOOD boat building, advice was helpful to you?  Note:They aren't afraid of wood in the bilge, as long as it is handled correctly.

[DaveBMusik]

Some additional info-
I spoke to Catalina today. The wood used was 3/4" hard wood (ash or maple) used as a stiffener sandwiched between the hull and the bilge.
They suggested drilling a couple of 1/4 inch test holes. They said the fiberglass in the bilge is fairly thin (a couple layers of 24 weight cloth) and should only have to go 1/4 - 1/2 inch deep with the drill bit.
If the wood is bad, it sounds like there is a procedure to cut the wood out from above (bilge) instead of dropping the keel.