View Full Version : Urgent - Keel Repair

12-03-2003, 07:31 PM
I have rennovated a 32 ft. twin-diesel-powered 1962 cabin cruiser.

It has a keel some 5 cms wide and some 17cms deep at the mid-section of the hull.

This keel tapers off GRADUALLY at bow end to be no more than 5 cms deep.

Similarly for the stern end, EXCEPTING that there is a STEEP TRANSITION.

As bad luck would have it, the rear harness of the travel-lift makes contact with the steep-transition part of the keel while lifting the boat in and out of the cradle.

This has caused a 5cm long crack to develop in the keel at this point. This crack runs forwards, at some 45š to the lower part of the keel.

Am thinking of fixing the crack at the same time as EXTENDING the inflection-point AFT by some 10-15 cms, so that the harness may make contact with a flat portion of the keel.

My proposed solution is to scarf-joint a piece of hardwood into the existing keel by:

1. Some 10 cms ahead of the cracked part, making a 30š-45 š cut in the keel until this cut reaches 13 cms up from the keel lower extremity;

2. Cut back (aft)till this piece of the existing keel is removed and then glue-in and fasten-in the new piece of hardwood, duly sized and tapered.

Is this at all feasible ?

Any special measures that need to be taken to avoid distorting / destructing the structural parts of the boat while I am doing it ?


Bob Cleek
12-03-2003, 08:21 PM
There are cracks and there are cracks. Assuming you are describing a crack which is not yet affecting the keel member structurally, but, as it seems, a crack at the hard corner as you explain, you sound like you have it under control. Scarf in a piece of the same wood with a good adhesive (Aerodux or epoxy) and perhaps fasten for good measure.

Now, on the other hand, if you are talking about a crack that is going through the rabet, you have a whole 'nuther problem. If the crack extends up into the keel and across where the garboard butts up into the rabet, you are into pulling planks, etc. Otherwise, you can expect leaking at this point, sooner, not later.

I'd urge you to 1) call your insurance carrier before you start any work and see if they cover repairing this as a casualty loss, 2) ask somebody who knows why the Travel-lift slings weren't positioned properly and consider expecting the yard to fix the damage, 4) don't believe all the "advice" you get in here, and 5) pay a good marine surveyor to look at it (small job, shouldn't be expensive) and advise you on the best method of repair.

12-03-2003, 08:53 PM
unfortunately, due to their own lack of knowledge, this is why we sometimes have trouble finding yards that will haul us.

Bruce Hooke
12-03-2003, 08:54 PM
What Bob said, except that I would avoid using epoxy in large wood members -- especially ones that are not completely sealed in epoxy. Epoxy can reportedly have problems if the wood it is gluing shrinks and swells a lot as a result of moisture changes, which I would expect would be the case in a keel that is not completely sealed in epoxy. Resorcinol has a good reputation for this sort of thing, the only issue being that it needs a tight-fitting joint and high clamping pressure.

12-03-2003, 09:52 PM
It might be useful to fit a steel plate on the bottom of the keel to ease the point loading of the lifting strap.

...32 ft. twin-diesel-powered 1962...

there's a lot of weight at this spot.

12-04-2003, 04:39 AM
Oi Carioca
Bob Cleek suggests:
1) call your insurance carrier before you start any work and see if they cover repairing this as a casualty loss,
If you have found an insurance carrier that will insure a wooden boat I would be interested in the name of the company. I have not yet found a carrier.
Sorry that I can't help with your keel problem ..... cuz I really can't even picture in my mind what you are talking about? However, I know a builder just across the bay that builds boats like yours. He would need to see a picture and I am sure Paulo could give you the advice that you need.

Bob Smalser
12-04-2003, 07:11 AM
Resorcinol has a good reputation for this sort of thing, the only issue being that it needs a tight-fitting joint and high clamping pressure. ...and temperatures of 70 degrees or more.

12-04-2003, 11:02 AM
[/QUOTE]...and temperatures of 70 degrees or more.[/QB][/QUOTE]

...apparently not quite that much, Bob. I've got the Aerodux technical stuff here, which says that you're fine from 59 degrees (15C) with the medium version and from around 50 (10C) degrees with the fast version. Moisture content of the wood seems to be important - best between 12 & 16%, acceptable between 6 & 25%. Over-warm environment with relative humidity way down is mentioned as a possible problem.
I submit this in all humility as a resorcinol beginner, just about to start doing test pieces with DF and Oak before taking the plunge with large lumps of boat. I've been picking up positive mentions of this particular new-generation resorcinol here and there.

All the best,

12-05-2003, 04:56 PM
Thanks everybody !

No, the blame may not be imputed to the Travel Lift crew at the Club. If they moved the sling slightly aft, they would risk damaging the prop shafts.

The crack is no more than 5 cms long, has not gone out to the rabbet area and is therefore under control.

Interestingly enough, I tried an epoxy-type (ARALDITE) fix around the crack area which did not work, confirming the notion that such cures do well only if the whole keel were set and sealed in epoxy.

Gerald, do you know if we get resorcinol in Brasil ?

Is CASCOPHEN glue, used by the older woodworkers / carpenters in Brazil, a resorcinol-type glue ?

I have tried CASCOPHEN in the past, wasnīt impressed and found 2-part ARALDITE (epoxy based) manufactured by CIBA-GEIGY in Brasil to be unbeatable for most applications, under-water ones notwithstanding.

also, we donīt have a temperature problem in Rio de Janeiro to jeopordaise the setting/curing of Resorcinol ! What, with "really cold winter days" at 15šC ? !!

Gerald, you may want to contact my insurance brokers in Rio who have a no-hassle approach to wooden boats, provided you do not mind their surveyor doing a thorough inspection on it:

(DDD code for Rio is 21) and ask to speak or send a message to Franklin at the following numbers

tel: 2532-0669; 2240-3633

fax: 2240-8682; 2532-6908

I shall send you gents a photo of the keel area as soon as I finish installing some new planks this weekend.

12-05-2003, 07:05 PM
I am going to Blumenau for a graduation ceremony this weekend. I will stop at the builders and ask him about resorcinol or what he is using. I have been using Scuna epoxy and products. I think the factory is there in Rio? I am sure they would inform you if resorcinol or equivalent is available.
Anything as dangerous to your health as resorcinol, could be, has got to be sold here in Brasil. I'm not real fond of the death part of the warning.
Thanks for the insurance info.

Health Rating: 2 - Moderate
Flammability Rating: 1 - Slight
Reactivity Rating: 1 - Slight
Contact Rating: 2 - Moderate
Storage Color Code: Orange (General Storage)

Potential Health Effects

Inhalation of dust causes irritation to respiratory tract. Toxic effects may follow and include methemoglobinemia, convulsions, and death.
Toxic! A poison to blood and nerves. Causes gastrointestinal upset with severe diarrhea, sweating, weakness, headache, dizziness, cyanosis, spleen damage, kidney damage, cardiovascular effects, liver damage, and possibly convulsions and death.
Skin Contact:
Strong irritant to skin, causing severe dermatitis and loss of superficial layers of skin. Can be absorbed through skin with severe exposures producing symptoms paralleling ingestion and enlargement of local lymph glands. May cause allergic skin reactions.
Eye Contact:
Strong irritant. Can cause permanent damage.
Chronic Exposure:
Target organs include liver and kidneys.
Aggravation of Pre-existing Conditions:
Persons with pre-existing disorders of the blood, skin, liver, kidneys or lungs may be at an increased risk from exposure.

Bruce Hooke
12-05-2003, 07:38 PM
All the resorcinol I've seen has been deep purple in color, so that will be one good clue (but not a guarantee of course) that you have the right stuff.

The color, the hazards of working with the stuff, and the requirement that the joint fit together tightly and be clamped firmly mean that resorcinol is usually something people use only when they have to.

[ 12-05-2003, 08:41 PM: Message edited by: Bruce Hooke ]

12-07-2003, 06:35 PM
I was able to talk with Paulo for a few minutes and didn't have time to ask about color of the glue etc. He has used and suggested, araldite compond or arcelino.
The information on Scuna products is as follows:
Tubolit Ind. e Comercio Ltda.
Rue Eloi Mendes 150
Prainha, Duque de Caxias CEP 25010 - 550 RJ.
Tel 21-2671-0162 Fax. 21- 2671 - 4281
I was thinking of how you might apply clamp pressure. Why not use the weight of the boat. Just jack it up and lower the area you want to clamp onto a block of wood?
Good luck

12-08-2003, 06:28 AM
No, I surely havenīt come across a purple-coloured wood-glue in Brasil.
CASCOPHEN (traditional wood-glue)and the only other local wood-glue that I have come across aside from 2-part ARALDITE, is an one-part brownish substance.

The cradle the boat is currently sitting on for the plank replacement job has actually contributed towards revealing the crack(keel supported fore and aft of crack)
Was painting the new planks with INTRNATIONALīs Intertuff epoxy-primer, so slid some of this paint into the crack and then shoved some paint-soaked woodpowder. Intertuff really glues on to wood and is intended for below the water-line application (ARALDITE seems not to be).
When the boat gets back to itīs own cradle, the packed-crack will come under pressure again.
Thanks for the bearings on the other glue supplier, in case I give up using ARALDITE.