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J/29 FROB, Hull #292, 1987. Wet as a J/29, clean as a well-maintained boat as much as I know & can say.  I Found her in the Buzzards Bay, years ago.
I did many upgrades & works and so far so good. When I got the boat , there was rusty stains in the bilge and around the two aft bolt. There were also 2 cracks around the penultimate bolt.  Since then, it's never grown nor got another crack even with our freezing winters. 
I can now keep bilge dry. No water from outside come inside since I have it. The keel joint seems okay but I recently found a kind of hollow spot (Delamination in a portion of a bilge wall?)  with, right on top, flaky epoxy coat (Interprotect).  So now, before to do anything,  I want to lower the keel to see if there is crevice corrosion on bolts.  If so, that may be the end of the story.
Any SA have lower/drop the keel?  
How low is the keel joint from the hull? (I can estimate the area but try to get there the more quickly/accurate as possible) 
What`s look like the shape of the lead?  
Any suggestions or good/bad experiences to share on this operation?
 
Just started to sand today and got this after 1.5 hours.

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The sump goes down 8-12”.  Drop the keel inspect the bolts and add sister tabs to the athwartships stringers.  It is not uncommon on the J29’s

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We have lots of what I consider to be the right tools.. metal wedges, vagg Th ious chisels, cutting devices 

 

ee approach the keel dropping abiding by a fundamental rule:

We can fix / rebuild/ reshape the top of the lead . We can’t easily fix either the sumP structure or the bolts.

so… we do our damndest not to hurt either hard to fix part. 
 

we hang the boat in straps and back off every keel nut an inch or so

then we attack the problem with increasing violence and destruction until the thing finally drops 

sometimes we grab the bottom tip and  rock it back and forth snd the jerk simply drops.

Really, I think it happened on a 77 J-24 in the nineties… or I dreamt it. 

cutting away some of the bedding with a 2” cutoff wheel on a die grinder gives us a place to drive in a few 3” wide cold chisels 

.. then More rocking 

cutting all the way across with a Diablo  50x thick metal Sawzall blade does wonders but BE CAREFUL that blade will cut right through stainless keel bolts. I g  Ed nerdlly font fo much Sawzall cutting unless the keel is going to the recycler and  the hull is going to a landfill

mstly, I swear J-boat keels were carefully designed to come off after about four hours of trying and failing, beating and cussing, and usually just after trying something everyone present agrees isn’t going to work 

 

 

 

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Lowering the keel is pretty straightforward. Loosten all nuts and back them off to top of threads. Do not remove the nuts, they become your stops.

 Block the trailer frame fairly level, take weight off springs, wheels still on ground. Lift boat with trailer pads. We like to use tall jack stands to aid lifting effort, 2 aft, one shorter vertical stand placed on trailer couple feet aft of bow knuckle.

 Lift the boat until keel is roughly 1" off seat. This is where Gouvernail's violence comes into play, follow his methods minus wagging keel. You have to wedge that thing down. "We" use splitting maul wedges pounding against each other. You can shove a pry bar from one side, if only one wedge available, slide wedge between pry bar and lead, near between hull and pry bar. Beat that wedge with the heaviest sledge hammer you can swing.

 Gouvernail's excellent method is with boat in slings, this next remark addresses your situation on the trailer. Always been a fan of his customer rants.

 Do not wag that keel, not ever, I mean NEVER wag that keel with keel even an inch off seat while on the trailer. You can cause damage but my reason is it tends to move, even rotate hull on pads. You need the boat to stay put on trailer pads. 

 Once the keel pops loose and drops the inch back into it's seat screw the boat up till sump hits nuts you previously backed off. Make sure all nuts are equal distance from sump. 

 This method controls boat and keel position during the process. When you are done with sump effort simply lower boat back onto keel, align, rebond and tighten nuts.

 Your keel doesn't look too bad as is. Maybe the boat ran aground previously causing the sump cracking.

 Last time "we" dropped a J29 keel...........I just don't have the energy to fill in the blanks, haha

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Thanks guys for your input. I looked somes of your others posts on the subject... interesting!

Yeah, my plan is to lower that bastard on the trailer by raising the boat with the pads.  So far I work slowly, a little bit with a wood scisor and a lot with a osciating tool... That one work great.  At the end I will have to use the wedges approach.


For anyone that may search for the joint on such bathtube, mine was 9.5" bellow the hull at the middle of the keel.  Higher in aft, lower in front.  

First I found out that the fairing was more thick than I though.  More I dug, more shits I found.  Of course, what could I though, a 35 years old J...

First discovery, the keel, bellow the joint was eaten of 1/8" - 1/4" deep by 3-4" bellow the join. Look like someone learned how to use there a grinder and didn't care to do a clean job.  Almost funny.

Then on starbord, at the middle, I have exposed a spongy black joint that responded to my hammer with water bubbles (pic with my finger).  So great.

All along this part, about 1.5', the bilge wall is cleary delaminated.  I can see the space between layers of glass.  Shits happen.  

Somehow I can imagine an original flat structure (pic with my finger, above the joint, partgrey/brown) from foward to aft on top of which fairing have been added by previous owner to give a nice shape to the keel (maybe something from Computerkeel, not idea).  For now I left all that in place and work on the joint.  


1 days later, without any rain, rust stains appeared.  So cool.  

So since the beginning the target is to say hello to the bolts...

Today I followed the join upfront the keel and I worked on the port side.  As I take off fairing on the front of the keel, I found a nice, clean, dry, untouch and cute unlaminated glass.  Such a great work, I'm looking for the yard who did that. I'm so impress...  On that side, I explosed very thick resin chunks.  The only positive point is that I saw no spongy black joint.  My moisture reader dont tel me it's dry, but doesn't indicated a swimming pool over there.

Anyhow, on that side,  keel is as well eaten  as starboard.

Beside the state of the bolts, the remaining questions of the day are :

Are the outside bilge walls are quite flat from foward to aft, flush to the keel head?  
Do I really see fairing added over the years, over the very basic bilge walls (that I can bearly see) built at factory? 
If I'm right and the bilge walls are as well delaminated, should they be rebuilt starting from the hull (ex: 12" on hull starting from the keel)?
Of course, if bolts are rusty as hell as I can imagine, all these questions can be irrelevant...

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  • 2 weeks later...

Got down the fat ass today.  Not the toughest job, but not easiest.

As told, I unscrewed nuts and raised the boat with the trealer's pads, about 1” in probably 10 or 12 minutes. 

Without wedge in hands, I used three axes.  It starts cracking just after 10-15 shots … but finally took two hours during which I ruminated your sentence Gouvernail:“…with increasing violence…”.Today was the peak.  Earlier this week I spent 4 hours with the oscillating tool to cut through the joint, from both side between the 4 aft bolts.

 

So… I found a bit I thought I would see.

The aft bolt has corrosion.  Maybe 10 or 15% of the diameter is eated. The bolt is black, telling me that osmosis is in the hole.   I get higher humidity readings in areas along the bolts. Will have to ask for the travel lift to get the keel out of my legs to and get a better view of the back of the sump.

During the work I took out all fairing... which is pounds and pounds! Just crazy!

Found 6-8 small holes filled with green resin.  Must have been drilled to fill some voids . 

I found a mesh type fabric strip on both sides, running from front to back, covering exactly the line separating the wide and narrow part of the sump.  Not sure if that strip in a good thing… but for sure the keel was smooth like an ass for years, with no cracking.

The narrow part of the sump is about 4-5” high and from there, the wide part goes to the hull.  Is the sump had really two wides like this, I mean stock from the factory? (I can see that from the inside of the boat but I’m a bit surprise to see that at the outside.  I can’t figure out why the width is not a constant and smooth curve falling on the lead?  That would required least fearing, no?   

Done most of the job with chisels. Of course, gelcoat chips got down but anyway my plan for now would include to sand former gelcoat down to glass and then laminate new fabrics. No idea how thick or who will do that.  But that is part of the plan; remove gelcoat and work from there.  Probably glass & resin, gelcoat, layers of interprotect/epoxy and fairing.  At least 5-6 epoxy layers, not like the 3 layers (at best) that I interpreted today by the sequence of color on top of the fairing.

And of course, a good damn joint.  And I would like to keep it visible, at least for a year or two.  Not sure if it is a good idea from a fairing standpoint.  Maybe the later job will never be stable and will always be quick to crack and flake.  for sure, that idea  can't help upwind.

Will see. 

For now I continue to clean and sand the area and I seek a good tech to get an experienced opinion at my shit.

Any of you folks have done such work on j29? yeah, but probably years years ago...

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Show us some inside pics. Some early J29's had vermiculite in the aft part of the sump similar to J24's. Most have been removed and filled with thickened resin/epoxy. 

The aft two keelboats were in vermiculite. 

I'm assuming this is what you're talking about regarding different levels of the sump? Your English isn't 100% clear.   

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We actually just dropped a 29 keel this spring after a customer hit bottom hard. I don’t think the boat was taking on water but the surveyor wanted the keel dropped and rebedded along with ensuring the bolts were okay. Boat was almost certainly freshwater only as the bolts were pristine.

After rebedding the keel, we ended up rebuilding the joint/fairing between the stub and lead with CSM (no fairing compound) leaving a few nails tapped into the joint so mark it’s location. We had nearly 1/2” of laminate to build up to match the two together in places. The original/previous work was a mess like yours. The client elected to have us router a 1/4” slot on the joint — just exposing the lead and original sump — to be filled with Sikaflex. The intention was if he were to touch bottom again (low water lake) it would be a much easier process and wouldn’t delaminate the fairing.

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Yeah, I know, my English is as bad as my previous keel joint!...

The picture with washers is the aft bolt, the one with corrosion (previous post).  The black around the bolt seems to be the same black on the bolt that I mentioned in my previous post.

The next picture is the penultimate bolt, the one with the cracks. Last fall I took off the wood floor and clean all the mess (the other picture).  We can see at least one crack goes in the glass.

It seems that all the rust stains come from the aft bolt. With all the stains, I suspected to find more corrosion on bolts.

For sure I don’t like the state of the floor/sump under the last two bolts.  Is that what we call vermiculite?

With the last picture, you should see the two widths of the sump.  I don't know if the narrower part is stock or rebuilt by previous owners.  The upper part of the keel is grinded to fit to this narrow part.  With you comment Will1073, I understand that other J29 have the same shape of sump.  And yeah, I have the same idea of you client, keep the joint free of fairing.  If the Sykaflex and the fairing are well done, I don’t thing it will do a difference on the upwind performance and it will be much easier to drop again that fat ass.  I just don’t know if such fairing will be stable over the time or if it will crack soon…20201002_150214.thumb.jpg.71f29a171a0f78c30007b31552ce7368.jpg

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On 7/17/2021 at 10:16 PM, sailman said:

The sump goes down 8-12”.  Drop the keel inspect the bolts and add sister tabs to the athwartships stringers.  It is not uncommon on the J29’s

What do you mean by "add sister tabs" to the athwartships stringers?  Double the thickness of each of the 10 or so stringers?  Or just the ones over the sump (4 I think)?

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5 hours ago, LarryMcFlY said:

What do you mean by "add sister tabs" to the athwartships stringers?  Double the thickness of each of the 10 or so stringers?  Or just the ones over the sump (4 I think)?

Several J29s have added stiffeners to the existing stringers over time, primarily over the sump.  

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6 hours ago, sailman said:

Several J29s have added stiffeners to the existing stringers over time, primarily over the sump.  

I haven't seen stiffeners to the stringers(floors) but it is common to re-tab all the floors and do a "sump stiffening" The sump stiffening entails adding additional layers of laminate between the floors where the hull meets the sump(and down into the sump) J Boats did this as warranty work on many newer J Boat models. 

I knew a J124 that had it done in the water! 

The tabs in the boat above looks great. None of the tabs look broken(as far as I can see from pics). 

The two aft keel bolts were where the vermiculite used to be.  

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1 hour ago, Squalamax said:

I haven't seen stiffeners to the stringers(floors) but it is common to re-tab all the floors and do a "sump stiffening" The sump stiffening entails adding additional layers of laminate between the floors where the hull meets the sump(and down into the sump) J Boats did this as warranty work on many newer J Boat models. 

I knew a J124 that had it done in the water! 

The tabs in the boat above looks great. None of the tabs look broken(as far as I can see from pics). 

The two aft keel bolts were where the vermiculite used to be.  

What I have seen adding sisters to the stringers.  Hard to tell of the tabbing was beefed up

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