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[Indian Falls]

I started the arduous task of separating the keel from the stub.  It's been 3 years of research on and off this forum, reading everything I can get my eyes on.   For me and my lack of fiberglass and boat experience the stories of Keel re-bedding are lacking some details, so I go into this with a great deal of apprehension.

The plan is to cut the fairing and fiberglass along the joint.  I'm using a 3/4'' wood chisel so I don't have to grind and make hazardous dust. In an hour I got 1/3 of the way around, just following where the lead meets the stub, cutting the glass mat so that when it lets go, it won't tear anything.  

The mast is up, the keel bolt nuts will not be removed.  If the keel just falls away as the boat is lifted, then hardwood 2x3's will be placed in the gap and the boat set back down, keel bolt nuts snugged to accommodate a drying and cleaning stage.  I'll be ready with oak wedges and sledge hammers if not.
The gap at the front is close to 1/4'', and the joint seems tight and gap-less 2 feet behind the leading edge.
The wedges can get a good start at the front.

Once clean and dry, 3M 5200 will be slathered on the surface.   The keel nuts will be tightened only 35 ft/lbs. Until Cured.  Then at the recommended 105 ft./lbs.  

Cleaning up the joint after this with glass tape and epoxy will depend on what it looks like when done.  My cutting operation is only about an 1'' wide along the joint, and glass is only 3/8'' thick in some places along this line.

Water has leaked out of the joint all winter.  I could not keep up anti freeze with the water coming down the mast this year.  The few times we had some cold weather it was preceded by lots of rain.  The rain water freezes and makes my keel joint worse.  I did do the sealing of the keel nut washers the year before, however this was not successful.  Water came up around the washers after a few weeks.  This method may keep the water out of the bilge, but it does not eliminate access to your keel bolts from the lake or sea, and I'd really like to seal this one up like it's supposed to be.

Any advice is welcome!

[added for searches: Catalina Smile - Stu]

[Rick Johnson]

Have you seen this link?  I realize it's not a c34, but perhaps it would give you some ideas.

http://www.wbryant.com/StellaBoat/hauls/0811/index.htm

Please take lots of pictures and notes.  I'm interested in this project for my C34.

Cheers,

Rick

[Indian Falls]

I did see the Stella before, but same as most, some of the more mundane details are missing as far as a novice like me is concerned.
 
It took 2 hours total to cut down to the seam with just a 1'' chisel.  I just kept working along the top of the lead.
All the keel bolts are now loose.   Water ran out of the joint as I progressed.  I was prepared with 8 hardwood wedges that are similar in shape to wood splitting wedges but a bit longer at 12".  The gap in the front will be a good place to start if it does not let go when hoisted.  I'm not planning on completely extracting the keel bolts from their holes.  Just get it open, dried out and clean.  We'll put it back together in a few weeks.

Thursday a few days ago, was the day we were to lift the boat, but the travel lift has a flat and couldn't be used.
More to follow as soon as they find a tire for it.

[Rick Johnson]

I'm very interested in this project.  Please keep us posted.

Cheers,

Rick

[Indian Falls]

Separation anxiety!

Finally got a travel lift under the boat Saturday.
Picked her up with all the nuts at the top of the threads.
The keel remained glued to the boat with whatever was used at the factory.  No popping sounds no cracking sounds, just solid silence.

We took this opportunity to realign the cradle since the lift was not exactly in the same spot as when set.
There were no cracks large enough to put the thin edge of the hardwood wedges in.
I started at the "smile" and used a hack saw to make a cut as deep aft as I could.
I'd get a wedge in there but the strength of the wood at that thickness was not enough to cause the wedge to start wedging, just break apart.  I worked the saw cut a bit with a wood chisel to open it up more.
I got a wedge to bite on each side.  Then got another wedge next to the first.  Once they get in about 1/4'' the hardwood is solid enough to start wedging.  I had 6 wedges on the port side all next to each other.
At this point it still did not seem to be giving.  The wedges were 2x2 hardwood about 12'' long.
I got in there with the BFH (1lb ballpeen) and started pounding on all the wedges like I was playing the xylophone from hell.  That's when things started to budge.  within 2 minutes the keel dropped the 2'' to the board in the cradle. There was a lot of diesel fuel in there.  There is a large void right in the center.  My fuel leak 2 years ago, putting 2 gal of diesel in the bilge leaked down through the bolt holes.  I previously posted that I suspected water leaking in was pushing diesel back up into my bilge all the time.  I was right.

Another mystery solved: RUST.   Why is there rusty water coming out of the smile?
Answer: there are two steel lifting points cast into the lead, 1 between the first 3 anchor bolts and 1 in front of the last 2.

I wish I had removed the washers when I left the nuts on top of the threads and removed the rags that were in the bilge.  As the keel descended it pulled rags down through a few holes with the threads.

I do not want to fully extract the bolts from their holes for 2 reasons: I don't want to build a stand for the keel and I don't want to go through the pain of trying to get the bolts back in the holes after it looses alignment by being free from the stub.  

We put three 2x2 hardwood blocks 12'' long in the gap.  I lifted the keel up with the bolts  and tightened a bit.  Those bolts have no problem lifting the keel.  We did this so the Yard can set the boat down without me if they need the lift during the week.

Next step is drying out and thorough cleaning and removal of excess epoxy.  
What ever was used to glue the keel on, is grey in color and brittle like cast acrylic plastic.

The thought of backstay tension occurred to me in this process.  I question If I should apply considerable backstay tension during the glue up of the keel stub?  I don't like the idea that tightening the backstay and pulling the ends of the boat up opening that joint at the front or at least be constantly applying stress there aiding in the crack occurring again.  Pull it up hard and let it cure thus putting stress in the opposite direction as in closing the crack.  Is this possible?  I think I read somewhere here that you can distort your hull with too much backstay tension.

What is the best choice for cleaning up diesel fuel in this area?  Mineral spirits? Simple Green?  De-greaser used when painting cars?  All of the above?

Any thoughts there among our experts concerning the hull distortion and the de-greaser ?

[Jim Hardesty]

Thanks for documenting the process so well.  I appreciate you taking the time to post here while you are doing such a big job. 
Jim

[Paulus]

I have used Valvoline: Brake Parts Cleaner.  It works great on grease and diesel fuel, used it when I spilled a little changing the fuel filter.  Finished cleaning with hot water and a good degreaser soap. I think that I would also pressure wash it with hot water after I was all done.  Keep us informed.

[Ted Pounds]

I believe what Catalina used to seal the keel joint was 3M 5200.  Sticks almost like epoxy... 

[Indian Falls]

After a good 2 weeks of drying out, I cleaned up the mating surfaces of the keel and keel stub.

I used 2 wood chisels;  a regular one and one with a nice long extension.. pictured.

I removed as much of the original epoxy bedding as I could still leaving some "refererence" surface for alignment purposes.

I found that there was a .125" to .25" void in the epoxy between the bottom of the keel stub and the "applied" epoxy laid on top of the keel.  It reached all the way back to the last two keel bolts.  Once the "smile" occurred, the water had a veritable tunnel to nearly all the keel bolts. 

This void contained silt, rust and diesel fuel. 

I chipped away all the voided area to expose the bottom of the keel stub.  Which is not flat at all.  It is very domed up and difficult to fill due to the ensuing air pocket.  I drilled four .25'' holes in the bilge floor to allow escape of air when the boat was lowered on to the keel.

First off, we raised and lowered the boat to insure there were no problems or hang ups when seating the stub to the top of the lead keel.

Second, I left the keel nuts on the top of the threads so there was no chance the bolts would disengage the hull.

Third, we used 2 caulk guns to put 4 tubes (.1gal ea.) 3M 5200 in the center of the keel area.  I did, prior to this, use a wire wheel in a drill to remove dirt, and lead oxide.  I washed everything with Prep All from the local NAPA.

We set the boat down on the keel, then picked it up again to view the distribution of 5200.   We put 3 more tubes of 5200 in there and repeated the set down/ lift up procedure.  I added the last and 8th, tube into the center area.

We set the boat down again, satisfied with the distribution of squeeze out and began to tighten the keel bolt nuts.

I only went with 35 foot/lbs and tightened up all the nuts.  5200 squeezed up under the washers and out the four holes I drilled in the middle compartment.

We set the boat down in her cradle just like you would for wintering over.  I went to tighten the nuts to 50 foot/lbs but I could hear glass snapping and cracking, so I decided not to "flatten" the domed keel stub by running the nuts down.  We'll torque them to 100 foot/lbs. in 2 weeks.  NOTE:  the front of the keel where it meets the stub opened up a bit after setting her down for long term storage.  I used my putty knife and mashed some more 5200 in there.  Still wondering if some heavy back stay tension at this point would be good or bad....

Using duct tape to ward off the squeeze out prior to applying the stuff, I smoothed and pointed the joint from the outside.  It takes 48 hours to be tack free, and 8-10 days to cure.  Plenty of working time.  I think we lifted the boat off the keel four times to get the stuff fully distributed, only about half of one tube squeezed out.  So 8 tubes of this stuff was just right. 

I'm going to make a large triangular plate to replace the washer in the forward bilge compartment.  This I hope will distribute the stress to the whole compartment rather than the area of the washer.

I was surprised at how thin the floor of the bilge is.  It's less than 1'' up front and bit over that in the middle.

[Indian Falls]

Remaining pics...

[scotty]

Thank you for this thread post.  I've been reading it with interest and ... hope to never have to do it myself!!  It sounds like you did a great job.  I noticed only one beer bottle in your tools picture; my, what restraint.    Let us know how it looks when you take it out next year.  Good luck!!

[Indian Falls]

This job was about 4 six packs to complete  thank you!!

I get the same "never thought of that" look when I question self appointed experts in this area whom are quite interested in my project and also overflowing with advice from paper gaskets to silicone... about the effects of backstay tension on this area of the boat.  The Commodore of the club was sharing a story where the fella had his shroud tension so tight he could not close the companion way.  I am sure that backstay tension has an affect but I have no way to measure or confirm how much.  There is nothing to suggest that this fiberglass hull is rigid like a concrete foundation.   My experience with bolting down large machines to concrete slabs is that you can pull up an 8'' thick reinforced floor with anchor bolts over a 12' long span enough to change a spirit level.  Ok that's not a lot, but it's always more than you expected and really messes up the project.

I'll keep tabs with the forum on the projects outcome.

Stay tuned!

[pablosgirl]

You can deflect a fiberglass hull with backstay tension.  Here is how to measure that deflection.  I use to race a J29 and that boat had running back stays as well as the fixed back stay.  This was a 7/8 fraction rig and the rigid backstay was used to induce bend in the mast to flatten the mainsail in higher winds.  The running backstage were used to control the forestry sag. A tighter forest at would flatten the job entry and depower the jib in higher wind conditions.  The windward running backstay would be tightened with the primary jib winch, which was quite powerful. So to avoid over fighting the running back stay we would determine the tension at which would cause the boat to bend for and act by running a small line from the bow pulpit to the stern pulpit so the line was just next to the mast but just not touchiing it.  The line has to be bar tight (straight) to give you an accurate measurement.  Now mark the mast where the line crosses the mast.  Next, we would tighten the running backstay until the line started to move above the mark on the mast.  At this point any further tension will bend the boat.  This also means that the fore stay will be as tight as it can be. At this point we would make a reference mark on the running back sheet so that during a race we would know the max tension point.  Since the c34 is a mast head rig boat the backstay works as the running backstay on a fractional rig boat.  So you can control for stay tesnion with the backstay  and bend the boat with to much tension.

[Indian Falls]

Thanks Paul! That's a great idea.

In hind sight, it's too late now, I would have put enough tension on the hull to raise that string an 1/8'' for the glue up and curing time over the last two weeks.  This would, in theory, put the opposite stress on the keel stub seam at the front.  And neutral stress when the backstay is tight.     "In theory".     

After two weeks, the 3M5200 is very much like silicone rubber.  It is peelable, stretchable, and unlike many of the descriptions about it in this forum.  I'm concerned that if it does not harden up more I will always have cracks appearing in the seam If I glass it over.  For this season, I ground the oozed out caulk down flat and painted over the seam with bottom paint.  We'll see in one year what this stuff is going to be like and decide then how to cover it or not.  Conversely, I'm not at all worried about water leaks into the boat.

It is my opinion that the bedding material used at the factory was merely epoxy.  The rumor that Catalina used 3M5200 may only apply to newer boats if at all.

I made some larger washers for all the keel bolts and a small plate for distributing the load on the front keel bolt out of .125'' stainless.  When I get to the boat next, I'll be removing nuts and washers one at a time and using these backer plates for the final torque down to 100ft/lbs.  Pix will accompany the next post.

[Indian Falls]

The second to last step in the keel re-bedding is to put the large backer plates on each keel bolt.

These are 3'' in diameter, .125'' thick and have a relief to allow clearance at the bilge wall.  The very last keel bolt got only a thick stainless washer as it's in that tight narrow spot in the aft area of the bilge.  Removing the 3M5200 from the threads, washers and bilge floor was no problem,  a little tug with needle nose pliers and it comes right off.
 
I needed to put some epoxy under the plate in the forward bilge compartment due to the surface not being flat.

Torque is at 70 ft/lbs and will be 105 or so the day we splash.

Next season we'll see what it looks like to determine the final step of re-fairing the seam.