Drying hull and seam splits

Hello,

My 1973 Grand Banks 48 is out of the water in Spain at the moment having extensive work done to make her safe (long story - unscrupulous broker, disingenuous vendor and a naive buyer (ME!)).

Anyway, the problem I have is that the seams are starting to show in the hull below (and above) the waterline and you can actually see light coming through on the inside. She has been out for 7 weeks and the average temp has been 25deg and 95% sunny: no rain at all. I have been hosing her down every other day for a good 40 minutes but this does not seem an adequate regime.

Should I worry that she will shrivel up too much (she is likely to be out for another 6 weeks or so)? Will she 'take-up' water when she is re-launched and how long will this take? What can I best do as a 'wetting' routine?

Boating was our retirement dream - can't seem to sleep to allow the dream to happen.....

kevp56 said:

Hello,

My 1973 Grand Banks 48 is out of the water in Spain at the moment having extensive work done to make her safe (long story - unscrupulous broker, disingenuous vendor and a naive buyer (ME!)).

Anyway, the problem I have is that the seams are starting to show in the hull below (and above) the waterline and you can actually see light coming through on the inside. She has been out for 7 weeks and the average temp has been 25deg and 95% sunny: no rain at all. I have been hosing her down every other day for a good 40 minutes but this does not seem an adequate regime.

Should I worry that she will shrivel up too much (she is likely to be out for another 6 weeks or so)? Will she 'take-up' water when she is re-launched and how long will this take? What can I best do as a 'wetting' routine?

Boating was our retirement dream - can't seem to sleep to allow the dream to happen.....

Click to expand...

Mate you need a professional boat builder to look her over not a forum

Photos of the " concern " gaps

As Gaston said, get a ship wright.
Once she is launched, she may have to stay in the slings over night with some extra pumps until she swells back up.

She will float again...

Greetings,
Mr. 56. Having owned a wooden boat for 12+ years in the past, your experience with "shrinkage" is not unique or uncommon. As Mr. b. states, she may have to sit in the slings for a period of time to swell up and become watertight.

MY opinion only: Do not caulk the open seams (the boards need room for expansion). Do not "fill" the bilge with water to hasten expansion (the hull was designed to keep water out, NOT water in). If you feel the absolute need to wet down the hull, you might place burlap sacks on the inside and keep them wet. Keep your drain plug open to allow drainage.

IF you do engage a shipwright, try to find one who is familiar with GB construction, if at all possible. Indeed, she WILL float again.

Aren't they carvel planked?

In the old days, we would caulk the routed gap on the outside, and any expansion needed was the gap between the planks inside of the "bead of cotton and caulk".

Not sure if all carvel built boats are planked and caulked this way, so a woodie Grand Banks guy would have to answer.

As to filling with water, all the wooden boats I worked on were hauled by railway so this is again for other opinions. But we did put water in the boat on the hard to swell the garboard planks, usually being the hardest to caulk well and keep tight.

Then pumped them and let sit in the water all day or night till the incoming water slowed to a trickle, but that was with all the planks seemingly tight to begin with....but there were always some leaks till the planks squeezed down on the cotton and caulk.

Get opinions on GB woodies and whether caulking obviously open seams is a good idea....most of the boats I worked on were locally made in NJ and most were lapstrake which is totally different.

Greetings,
Mr. 56. In light of Mr. ps's post, a few qualifications about MY comments. Our wooden boat (Chris Craft) was originally built with the planks tight against each other with NO cotton/oakum backing or caulk. Yours may have been built similar to what Mr. ps. describes.

Filling a wooden boat with water, to pre-soak, is as contentious a topic as, gasp, anchors...

I own a 1936 wooden boat that is out of the water from mid-October to mid-May every year. What I do is to tent the hull with plastic from the waterline down to the ground and pour 20-30 gallons of water a day under the hull for a week before launch. If I had running water where the boat is stored I would put a garden soaker hose under the boat to wet it down. I also pour water into the bilges daily for a week before launch to help swell the garboards (the planks next to the keel). That works well.

Also the boat should NOT be inside in heated storage or on concrete. It is best if it is on dirt or gravel.

Coming from a lifetime of owning old wooden sailboats, stored for winter on the hard and launched with many open seams in the spring, I picked up one old-timers trick that may help you. (LOL, now I am the old-timer!)
Just prior to launch, take a bar of hand soap and rub it across the open seams, forcing hard soap into the seam. This keeps the water out, and slowly gets squeezed out/absorbed as the wood swells over the ensuing weeks.
It is still a good idea to leave her in the slings overnight upon launch, and an extra bilge pump helps.
This worked for me for years, and I don't believe there are any downsides to this trick.

I suspect "hosing her down" is done to the outside of the hull only. I suspect in the weather you describe wetting the hull from the inside could make a huge difference. Blankets could be put where water would run off and the wood would dry out again in 20 minutes. One should be aware that too many wet blankets would be a lot of weight and a wood boat hauled is susceptable to hull damage from pressure on the support points.

But I belive moisture from the inside is important.

Mid 1900's.... during late 50's, all through the 60's and into early 70's... I worked on our family's wood boats as well as working at "boat yards" on a lot of wood boats; many different makes, models and different wood construction types.

So... I have a question for you: Did she float before hauling with little to no leaking into bilge from the water it was floating in. If so... she will swell-up and float again.

As has been mentioned here you will probably need to keep her in slings for a while and you may need an extra pump as her seams tighten-up. Hand soap forced into seams mentioned before is also good; it melts into water soon after launch. A trick we sometimes used on really wide open seams was roofing tar pushed into seams that had opened quite wide. Tar would squeeze out during swelling and create a "long" lump along the seam. So, don't put too much in... the seam just needs a little on the exterior opening to slow the seep till planks swell.

Basically, as long as the boat floated before with no big leaks... I'd launch her as is and be sure to have agreement that it can stay in slings for long enough to get it so that water ingress could easily be handled by the boat's bilge pumps. I would also make sure I had an out source sump pump and electricity to run it on hand until the boat swells to point of little to no hull-water ingress.

We used to take boats out of slings soon as her bilge bumps could handle the flow. In other words... once the pumps could empty the bilge and be turned off until ample water again came in to restart pumps. Auto float switches can take care of pump needs.

Happy "Boat-Float" Daze! - Art

Thanks for your reply. She is carvel planked sapelle with evidence of cotton caulking. I have put a sea-water soaked towel in the affected area and this has helped considerably; it has certainly re-assured me that she will float again exactly as she had done before with little or no leakage (except for the rain-water from above which is killing her)!

Warning: Long sentimental story with little practical value coming....feel free to skip:

As a kid, launching the boat was one of the only things that could get my normally unflappable father nervous. Our club had some family type members, and then some boaters with a drinking problem, and then some alcholics with a boating problem. When the season began, the yardmaster was trying to get 150-200 boats in the water. Everyone was yelling at him to launch their boat next, and he was yelling at the guys were weren't ready yet, but were blocking other boats in. Then, the membership contingent that hadn't been down to the floats in years sat on the balcony of the clubouse ( ie: bar ) and took it all in as entertainment and were like the guys in the Muppets who sit in the balcony. The workforce was all the members who were in a hurry so their boat would get launched, and it took a lot of guys to pick up the 6 inch wooden rollers from behind the boat and run them to the front of the boat as it got dragged accross the yard. I remember being fascinated with the giant winch in the winchhouse, and all the blocks and tackles spread out across the yard. When it was finally your turn, you would climb up in your boat, roll down the railways, and for my dad, devout agnostic as he was, it was prayer time. You float off the cradle, toss a line and an extension cord to the dock, and buy the yardmaster a beer so he would take a break and you'd get more time sitting on the cradle. ( Obviously it was best to be launched earlier in the day ). Then, without ever setting foot on your boat, the yardmaster would deem the critical stage was over and start to lower the rail car to float you off. My dad would plead for a few more minutes...the gallery would tell him everything was fine as they ordered another round, and the guys who wanted to go next said everything was fine. The yardmaster would yell at my dad in French, my dad would use the entire list of words that would get us spanked ( don't judge, it was a different time )....and the boating season would begin.

Every year there would be a few wet carpets....but eventually they all floated, and I'm sure yours will too.

So good to hear there is someone else who remembers it the way I do!

Great story Benthic2. I'm only familiar with the annual process of haul out and launch from listening to my Dad and New York relatives.