Tech Tip #2, Moisture problems?

[MacGyver]

Today in a Hunter 260, we had to replace a C/Board line.
The inside was horrible with moisture, something the boat owner had asked me about in a phone conversation.

Upon inspection looking for the obvious like leaks, etc, we found nothing that looked suspicious.
Windows covered in condensate, and condensate damage on the wood covers over the storage areas.
The whole boat had sections of mildew, etc. The white hose covering the Center Board line was covered in mildew.

A big thing people don't consider and that I talk to many about is where this comes from... sometimes it is not the leaks you need to find, sometimes it is the amount of ventilation you do or don't have that is the issue.
To eliminate or help control moisture, you need to help to keep it dry, and by doing that, you don't want to close a boat up totally, which on this boat looks to be a big problem. A lot of boats have sections of double hull, where they aren't glued together except in spots allowing air space which compounds the issues.

Boats will warm quickly, and cool slowly. Just the way it works thermally with its environment. When this happens, condensate occurs.
To help combat this, only a few things can really be used. The big one would be a dehumidifier. I will suggest that on this boat, as it is really pretty bad.
After this has been done, I highly recommend a product called "DampRid". We used it on our boat this year, and it worked really well to keep the bilge dry, the boat was free of mildew, etc. I would suggest 2 on this boat just to help alleviate the issues. It certainly isnt fixing it all, just some.

We bought our "DampRid" at WalMart, in the RV section. 10 dollars and it is a 1 gallon ice cream pail of material with a filter cloth glued to the top. it has a lid to cover it. You basically set this where you want it, and take off the lid, leaving that filter cover in place.
On the side is a few dots, and when this darkness starts to show up at the red dots, time to throw it out and get a new one.

It looks like we will get almost 12 months out of ours. Less than a dollar a month is cheap. 

The point is to keep the boat dried out.

Something else that helps to keep the air moving would be a solar fan. These can be cut into a hatch, or installed on the deck, etc. They can be expensive but are usually very quiet and move air even at night due to a small battery.

I suggest you at least think about dropping in a "Damp Rid" unit. They sell smaller ones through the internet as well and some are refillable types.

Good luck to everyone with the moisture problems,
Keeping boats dry not only helps keep the inside smelling clean, and the mildew/mold out of the boat, but helps keep fiberglass blisters from forming amongst other issues  . I will get into that another day. 

Mac

[Bob23]

Mac: I appreciate your sharing all your knowledge. I've had a solar exhaust fan on the sliding hatch of my CP 23 for a number of years. It worked ok, but lacked a suitable intake. This spring, I installed a dorade box with cowl vent on the foredeck and another cowl vent on the rear of the boat to act as an intake. Because I'm on a mooring, the boat always points into the wind so a constant flow of air is a given. I've had no mold issues at all this summer.


thanks again... I read all your posts!
Bob23
   

[MacGyver]

Bob23,

Thank you for reading my posts! I hope they help, that is what I enjoy doing, helping others!

And a BIG thanks for commenting with your experience, as it shows that it helps to have ventilation.
It is surprising to me how many times, to new and old boaters, every year I explain moisture and ventilation.

Mac

[Salty19]

Couple of bucks for PVC elbows, some screen, wire ties and tap...viola-- vents.
They aren't pretty, but they work surprisingly well and were inexpensive.

[skip1930]

"DampRid" is a great product and container of it sits in my boat in wither storage as we speak along with half dozen sheets of stinky Bounce fabric dryer sheets. Mice hate those things. Bounce is also in the Model 'A'.

The boat and car sit in indoors in a 95 ft x 50 ft metal building, unheated, but the building is generally dry and closed up tight enough to keep the varmints out.
Last spring the color changing dots did not change color and so it must be pretty dry in the building and on board.

However my buddy who parks his boat in his back woods all winter with just a half ass trap tossed over it has condensation problems every year. And it has even ruined the original upholstery. He has one of these solar fans on the front hatch in hopes of moving enough 'wind' around inside...good luck with that. He just won't listen.

I stopped shopping Wal-Mart for personal reasons more than ten years ago. I go to ACE and pay a little more.

skip.

[Bob23]

My Vitus solar exhaust vent worked ok. Actually, after 7 years it's still working but I didn't feel it moved enough air around. Plus, as anyone who know anything about hvac, you need supply and return. My old passive vent on the foredeck wasn't allowing enough in and the Vitus wasn't strong enough to pull the air through. The cowl vents work great and the aft one provides exhaust which even helps to keep the bilge drier. I may run a dedicated hose from just above the bilge to the aft cowl to help ventilate the bilge a bit more. But not now...later.
Bob23

[brackish]

I replaced a passive cowl vent with a solar vent when I got my boat.  The rubber cowl vent was split and the plastic base was crumbling.  There is plenty of supply air space to keep pressure positive from the gap between the sliding hatch cover and the top of the drop boards.  In the winter I put a small electric heater on the cabin sole set to come on low (900 watts) when the temp dips below 40F.  I think it rarely comes on.  The heater has a tipover switch but has never tipped.  The marina does not meter my power because I don't live aboard or have AC.  My only other usage is the Guest 5/5 charger for the battery bank.

Despite the heater I still have to do my version of winterizing which consists of pumping my water tank dry and pumping in a gallon of non toxic anti freeze.  And dump the water from the porta potty.  The Marina's electric power is not reliable and if I get a surge it will kick my AC main with no one there to reset.

My bilge has never had a drop of water in it unless I put it there purposely.  I've done that to test both the twelve volt and manual bilge pumps.

With the system mentioned above I've never had a spot of mold or mildew nor any bad odors from leaving the boat, sometimes for weeks at a time, during the winter.

I also leave a bounce sheet in the cabin along with a chunk of Irish Spring soap.  Also in each of the cockpit lockers.  Not for mice but to keep the wasps from coming in and building nests in the Spring.  Seems to work.

[skip1930]

" I also leave a bounce sheet in the cabin along with a chunk of Irish Spring soap.
Not for mice but to keep the wasps from coming in and building nests in the Spring.  Seems to work. "

Out standing idea. Thank you.

When Butler Building Systems switched from force drying solvent based oil paint to lower VOC water base paint on their steel building trusses, Butler found it necessary to slow down the conveyor, increase the oven temperature, and add 1/3 more exhaust to atmosphere to keep the oven 'sweet' by reducing eye watering aldehyde's.

This burns more fuel to do the same job as solvent base paint and slows production. Two additional problem cropped up. Very humid days and flash rusting of the substrate from water based paints exacerbated the the corrosion protection warranty of their products, resulting in purchasing a more expensive coating for their product that Butler could then warranty. There is a big difference between a guarantee and a warranty. I luv's EPA intervention.

skip.

[Billy]

I put a bunch of cedar in my boat to keep moths from eating my sail covers.

And I think the damp rid is a great idea. However, here in FL I bet they would only last a few days though!

[WhiteShad-O]

Mac,

Please pardon me for getting off topic.  I need your expertise.  Today, I apparently did not back my trailer deep enough when hauling out the boat after sailing. The result is that the foreward edge of the keel on my cp16 sustained some visual damage.  The gel coat was scraped right off by the edge of the ramp in a couple of places. The roughness can be easily detected by running a hand down the front of the keel.  I expect a small amount of resin may have also been gouged as well.  I doubt this would compromise the structure, but it looks like heck and should be repaired I expect.

How can I go about this repair? I recall that gel coat won't dry in open air.  Should I just put some epoxy on it, sand it down and blend it in with the surrounding gel coat, possibly touch it up with paint to match? If so what kind? 

I appreciate any tips.  I was livid when I saw these gouges.

Eric Klee
Hudson, fl

[skip1930]

Clean and dry the area. Sand a bit of the paint off in the immediate area. Marine-Tex the divots. Sand a bit and paint. No biggy.

skip.

[MacGyver]

Eric,

You are right, Gelcoat doesnt cure in open air. some cover with plastic, some use use tape, etc. We use a mold release liquid, purple in color.
It forms a solid film to which no air penetrates. After a few coats of it, usually within a hour or so the Gelcoat is hardened.
I typically leave it over night to cure, just for good measure, and I try to keep from Rushing a job out the door.

Another option (I am sure Marine Tex is a good option..... Never used it myself, and have a few repairs on my boat the PO used it and I am not happy with the work.....) is to do this:
Clean out the gouge, and rough it up. The rougher the better. dont need to rough up the surrounding edges, just the actual damage.
In my repair work, I use West System Epoxy with a 404 filler mixed in to make a creamy peanut butter like consistency. This helps to restore the water tightness of the Gelcoat by using the Epoxy filler to smooth the damage back out. This gets you back to the "form" of the boat.
Then reapply the bottom paint after sanding with 80 grit sandpaper.

If the boat is trailer sailed, then be sure to find the problem that caused the issue before you repair, and fix that.
Small amounts of time in the water wont be bad on the boat. Fixing the issue first will ensure you dont have another accident to repair after already completing the first one. Most times you end up redamaging the repair you made

IF the bottom is gelcoat, then you can easily re gel coat it. Color match is a issue though, hard to nail it right on.
Let me know if it is a Gelcoat repair need, That is a bunch to get into but I am happy to share my tips and tricks to help you make a good repair.

Mac

I only recommend the West System, I am sure there are others (and  my garage has a few others alongside my west system setup) that will work, West System just keeps forever and if you think outside the box, has a huge list of ideas to keep the wife off your back around the house.... LOL