Re-sealing bottom seams

by Claude

I have an old century boat, has not been in water for 20 years, the bottom wood seems good, have poked around.

Ran the hose inside, it leaks terribly.

All the seams are letting water out.

Let it sit for a couple of days, and same thing again.

I have hoisted it up in a sling, and set it on blocks to access the bottom.

Have started to dig out the old caulking, which is hard as a rock.

I think I must remove the old caulking, before putting something new in.

What product would be best to use.

Thanks for any help,

Claude in Toronto

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Seams and Pics
by: BILL

Hey Mike, Yes did find it..after I ordered seam compound duh!

It seems to be one of those, "if you ask at the counter they will bring it out" but don't advertize it.

Will get some new pic's to you.

Hey would love to see a picture of the Century in this forum.

Always seen the Century Resorter, as such a James Bond type of to find one in need of some TLC!!

Boy my wife would just love two boats in the drive, along with the two canoes taking up the garage ha!

by: Mike

Hi Bill,

So you have been able to source red lead, that’s great.

I will have to remember that Tendercraft for the next time someone asks, thanks Bill.

Yea, that Slick Seam is only a temporary fix, something you put on just before launching which keeps the water out while the planks ‘take up’. But you can do that with some bar soap or even some masking tape.

If you want to add some pics, and I would love you to, you can email them direct to me, as attachments and I can add them for you .

It's déjà vu all over again
by: Bill Ottawa Canada

Wow, just finsihed going through all this with Mike and finding all the proper material in Canada.
(see my 1959 Andress in the project boat section)

I had advice coming from everywhere on re doing my bottom, but Mike, from this site, as well as a few other friends made the most, and best sence to bring back the boat hull. Yes Noah's is good, the other place in Tendercraft on Markham Rd in Toronto for cotton and seam sealers...Tendercraft is the ONLY place I can find red lead in Canada so far!

I carefully took all the old red lead caulk /sikaflex and cotton out slowly with a hooked screwdriver thing. primed the seam areas with bottom paint. Now ready to add new cotton, paint over then fill the seams with compound. So far so good! I would stay away from Slick seam as it tends to fall out, basically wax.

I will have to post some pics of where I am at now with mine.


Bill in Eastern Ontario

by: Famille

If it hasn't been in water for a long period it will leak no matter if the wood is good.

The planks need to "take up" before you know if you really do have a problem.

Tap around with a rubber mallet (you can hear any rotten areas) You can run water through for a few days, or use a sprinkler from the bottom side until the wood swells up, at that point you'll know if you have problems.
May just need a bit of caulk in the leaking areas, may need new cotton and seal, may need a whole new bottom, but it's hard to tell without it swelling or seeing pics?

Time and a garden hose:
by: Dave

It takes about three days for the bottom of my 80 year cutter to tighten up if shes been out for a long time.

I spary it the hull down with a garden hose for serveal hours over three days, simple lawn sprinklers work great and will help you from flooding out he boatyard and you neighbors.

I don't use alot of water, it just takes time for the wood to expand.

Then I ussually run over the seams with a little" slick seam"> green waxy stuff", in any areas thst I think might weep.

Then all is well.

Good Luck.

Re-caulk an old century boat.
by: Mike

Hi Claude,

After 20 years out of the water the timbers and caulking will have dried out and contracted thus opening all the seams.

Depending on the timber it can take quite some time for it to 'take up' again to close the seams.

However, after all that time out of the water and with the caulking being hard then you will, as you say, have to dig it all out and re-caulk her.

As you have probably already found out getting the old stuff out without damaging the edges of the seams isn't easy.

But that is the hardest part, the re-caulking is, I think, quite a pleasant job.

As you are in Toronto Noahs are probably your nearest stockist of caulking gear.

They stock Pettit Seam Compound, which I haven't had personal experience of using but I have heard good reports from those who have used it.

They also stock the most important element the cotton.

Interlux also do traditional style caulking compound but I always think it is best to use the nearest supplier, it keeps carriage costs down and if you run out it makes it easier and quicker to get some more.

After 20 years she deserves a bit of TLC,

Best wishes with you project,


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