Caulking below water line

[Compass Rose]

Anyone have any recommendations for caulking a boat these days . I have been out of it for over 15 years and I know there is always new products out there. I have to re-caulk a 33" century that has been out of the water for 5 years in a shed. I fiqure it is the best time to get rid of all the old bedding compound . However I am up in the air about what to use. She is going to swell up tight for sure and i want to be able to have a lot of expansion with the compound and do not want to pop a plank.

Would it be better to use underwater bedding compound or boatlife?

[Flitch]

Well, now you have done it Junior... and just when we were starting to get back to some semblance of harmony on this forum... You see there are a portion of members who subscribe to the old tried-and-true methods which involve after reaming the old seam compound out and servicing the old oakum or cotton, using an oil base primer (red lead, bottom paint, etc) and interlux seam compound which can be appplied with a knife, or squeezed through a caulking gun... some members with a flair for adventure are using CPES (Clear Pentrating Epoxy Sealant to prime the joint and a modern Polyurethane (3M 4200, Boatlife, etc) to seal the joint... I for one am thinking of doing red lead and Interlux seam compound on one one side of my boat, and CPES and 3M on the other...
PS this would be a good time to take cover...
http://www.flickr.com/photos/kootenayman/sets/72157603832016101/
Flitch

[jimmy]

One trick that might not be new, but is at least new to me is to swell the hull before caulking it. One way to do this is to put a plastic curtain (vapour barrier, etc) all the way around around the boat and put one or more humidifiers inside. This takes a lot of the uncertainty about how much she will swell. Some searching will turn up some photos of this being done on a very pretty boat recently.

[pcford]

If the boat is, as the original poster writes, "a 33" century " then it was a batten-seam boat. Century did runabouts, but they did do a few small cruisers as well. These did not have normal caulking seams. Nor did they have a double planked bottom like Chris-Crafts.

I would check the bottom fasteners. If needed, I would refasten. Then I would put in a polysulphide seam compound. A two part is the best. Boat-Life is an inferior product in my humble opinion. Polyurethane is too stiff.

Caulking techniques with cotton etc. are off the mark. The boat was not built that way.

[Ian McColgin]

pcford is right on target, assuming she's a 33 foot (33') Century and not a 33 inch (33") century.

But my remarks must stop there as my only experience with seam batten is plywood epoxied to the battens - a very different matter.

G'luck