Caulking, Priming, Painting Hull on lapstrake Cruiser

Berta'sBeauty · Post by **Berta'sBeauty** » Tue Jun 07, 2011 4:39 pm

Hello Everyone,
We are in the process of repainting our Cruiser. The hull has been sanded smooth and is ready for repair caulk, primer and paint.

We purchased Interlux Brightside Blu-Glo white and Ocean Blue to paint above and below the water line.

We need to know what kind of caulk and primer to use before we paint. Have seen some comments on Boatlife caulk and wondered if there is a preference for what type to use. We also need to know what type of primer to use.

Any help would be greatly appreciated!

Thank you,
Roberta

LancerBoy · Post by **LancerBoy** » Wed Jun 08, 2011 4:29 am

Use a priner that is compatible with your paint. I'd stick with the same brand primer as the paint.

BoatLife is a brand of marine caulk.

What are you caulking? Are you lossening up the planks and caulking between them and then refastening?

Andreas

Berta'sBeauty · Post by **Berta'sBeauty** » Wed Jun 08, 2011 5:18 am

Hi Andreas,
Thank you for your response.

We will get the brand primer you recommend.

No, we are not loosening up the boards. We are just going to caulk in any areas that we see needs repair. Most of the caulk looks very good.

Roberta

THE LAKE · Post by **THE LAKE** » Fri Jun 10, 2011 5:27 am

As I read Don Dannenberg's "" Wooden Runabout Restoration Guide" there is quite a bit of information on how caulking dry seams will cause the planking to split apart when the wood gets wet and swells. Just thought I'd toss this out there as a caveat on caulking where perhaps none is needed.

Brian

LancerBoy · Post by **LancerBoy** » Fri Jun 10, 2011 9:31 am

Danenberg's books relate to carvel planked boats with solid lumber planking. This is not as serious with a plywood planked lapstrake hull. The plywood swells and shrinks very little compared to solid lumber.

Andreas

Berta'sBeauty · Post by **Berta'sBeauty** » Fri Jun 10, 2011 10:49 am

The caulk is pretty sound, it is just rough looking... as though the previous person did not smooth it out very well. The boat was in the water last summer and did not take on any water. The inside seams are very clean as well as the boards.

We are just going to go over some areas with a good silicone caulk. Prime and paint. I think this will be sufficient.

Thank you for your responses. I appreciate the help!

Phill Blank · Post by **Phill Blank** » Fri Jun 10, 2011 12:57 pm

Roberta,

I do not recommend using silicone caulking. To hard to remove in the future and often new caulking will not stick to old silicone caulk.

I recommend "Boat Life" caulkings. Made for marine use and can be sanded and removed in the future if need be. Also it has good adhesion and stays flexible allowing the wood to move without causing any problems.

Boat Life caulk is not cheap but is worth the money.

Good Luck,

Phill

Bill Dunn · Post by **Bill Dunn** » Fri Jun 10, 2011 5:52 pm

You will also have a hard time getting paint to stick. I made the mistake of using silicone caulk around the windows on my house about 20 years ago and still have some spots that won't take paint.
Bill

Berta'sBeauty · Post by **Berta'sBeauty** » Sat Jun 11, 2011 8:12 am

Thank you all for your comments. We are now re-evaluating what to do. We certainly don't want to create a situation that causes us problems in the future!

We hope that the caulk that is there now is not silicone caulk... I don't think so, but how would we know?

Torchie · Post by **Torchie** » Sat Jun 11, 2011 8:38 am

How well is the paint sticking to it that is currently on there?
Bill is correct inregards to paint sticking to it although I believe that they now make some that is "paintable"
As Phil said it is hard to remove, tends to look like "flubber". Anyone remember that?
Will be very stretchy unless it is really old and then chances are it isn't silicone.
Karl.

Phill Blank · Post by **Phill Blank** » Sat Jun 11, 2011 8:42 am

Roberta,

Generally silicone caulk will have a shin to it's surface or when you cut it with a knife the surface will have a shin and be rubbery. Most other caulking will not have this shin, but there is no possitive way of knowing until you try paint it or applying caulk in the area again.

Best is to strip out as much of the old caulking as you can and recaulk and paint.

If what was used was Boat Life you should be able to sand it smooth and repaint. Boat Life will remain rubbery for it's life. Also it needs to cure completely beofre painting or the paint will not dry until all the solvent has evaporated from the caulking. Follow the directions on the tube and you should not have a problem.

Good Luck,

Phill