MacGregorSailors.com

I was lucky enough to obtain a wet slip for my '05M at Lake Hefner, a nice sailor's lake a few minutes from my home. My son will have much more fun now that he won't have to endure dad's grumpiness during rigging and breakdown. Right now, he thinks sailing starts and ends with an hour of his father making him run back and forth for tools and parts.

Any members here keep a Mac or any sail boat at a marina? Do you advise keeping the ballast tank full or empty? Any other suggestions or tips?

We're doing the same thing next year, and will also appreciate answers to Rick's question. Do we really need barrier paint under the bottom paint to prevent blisters?

Don't know about Rick, but we won't have shorepower to run the lights off or hook up a charger too. Have thought of one or two of those flexible Unisolar panels.

The security thread probably applies here too.
--
Moe

rick + moe, i have my 26x in a slip for 6 years now, 4 years on freshwater, 2 on the baltic sea.

i would higly recommend a botton paint. to prevent blisters you have to apply sevels coats of epoxy paint (normally 4 to 8 depending from the manufacturers advice). it is a lot of work if you decide to do it yourself (or a lot of $$ if you go to a shipyard), but it is the only secure way to protect your investment. it seems that fresh water is even more dangerous than salt water (osmosis physics...).

depending of the marine growth situation on your home waters an antifouling is also recommended. ask the folks in your marina wich works best (you'll have 20 different answers from 20 boat ownners, but you'll have an idea which brand to choose).

I will be mooring mine every season now that I have been spoiled by 3 months last summer. Maybe I'll increase it to 4 or 6 months. I don't have botttom paint I just put a good coat of wax on then pull it out every 4 weeks and power spray the bottom with a Simonize 1600 pressure washer. It grows a green beard pretty fast and the barnacles reappear quickly too, but I am loathe to coat the bottom with anything but wax or perhaps one of those new superslick applications I am hearing about.
I also read somewhere that some environmentalist lawyer is trying to get that antifouling bottom paint outlawed in the states and if he does everyone will have to have it removed.
Keep an eye on the marine news.
I usually emty the ballast before heading into the marina but I have noticed that another owner has left his ballast in all winter and others are laughing about it. I'm not really sure if it matters for the short term say weekend to weekend if you forget sometimes but leaving it for 6 months is another story.

forgot about the water ballast. i always have it full when laying on the dock. less boat movement, more quiet sleep. i rarely dump the ballast during the season as i am mostly sailing (shure that i dump the water ballast before winter storage).

terry, epoxy coat is to prevent the grp from osmosis and delamination. gel coat ist not really watertight. when the boat stays more than 4-6 weeks in the water molecules penetrate thru the gel coat in the hull material and causes delamination (seperation of glassfibres and resin). this can be a major damage. blisters are the small symptom of this (trailered boats are not prone to blister as the grp can dry out when the boat is on the trailer). sweet water is even more dangerous as salt water (as the molecules are smaller).

antifoulings should be adapted at the marine environment. salt water slipped boats need more toxic antifoulings than sweet water ones, warm areas more than cold regions. tributyl tin antifoulings are extremely toxic and illegal worldwide on recreation boats. copper antifoulings are still the mostly used anti-growth paints. but there are some non-toxic antifoulings available for inshore use. in a cold northern sweetwater lake you may easily manage the bottom of your boat without any antifouling paint. but -again! - if you di it without an epoxy barrier coat you take a high risk for you vessel.

Norbert,
I do not know what grp is nor was I aware of the delamination problem you mention so now I have reason for concern as this is new to me. Does wax not work? What about those teflon or silicon based waxes or that Newglass 2 stuff will that work or do I really need to get some epoxy based preparation. Also can you or anyone recommend something now that I have yet another job on my to do list. Just when I thought everything was in order for this spring along comes another problem to take care of.

GRP = Glass-Reinforced Plastic (or Polymer) = Glassfibre = Fiberglass

For what it's worth, Tony Staton-Bevan's book, "Osmosis & Glassfibre Yacht Construction" is pretty much the Bible on the subject. I highly recommend it to any yachtsman's library.



And Norbert, in most cases I would agree with your statement:

"(trailered boats are not prone to blister as the grp can dry out when the boat is on the trailer)"

But this is *not* the case when the boat in question is a multi-layer hull (foam, balsa or other cored).... Moe, this is one for you to take note of, as Boston Whaler's are prone to leakage between the outer hull skin and the inner foam.. once the foam gets saturated it's nearly impossible to dry them out and blisters will quickly follow.

Fortunately, the Mac's are not multi-layer and don't have this particular problem, but they are not immune from blisters if left in the water for long periods.

The formation of blisters is due to the reaction of the glassfibre chemicals with the water, forming a rather distructive acid... and the glass can be greatly weakened in the process.

I have anti-fouling bottom paint. A full ballast while docked seems to be the most convenient, as Norbert said. But is there a threat of osmosis internally in the ballast tank if I keep the ballast full for exented periods? I assume that the ballast tank is GRP and not lined or painted? Is this correct?

Rick wrote:... is there a threat of osmosis internally in the ballast tank if I keep the ballast full for exented periods? I assume that the ballast tank is GRP and not lined or painted? Is this correct?

Correct, there is a threat. I'd drain it unless I needed it, but that's my choice and not everyone will agree.

I don't know much about this subject other than my own limited expieriance. I had a 1986 Mac 25 that I kept in a slip at a fresh water lake for 3 years and I never once pulled it out to clean the bottom. No wax, no bottom paint, and no blisters. The boats previous owner was similiarly neglegent for the 3 years she kept it on the Sacramento Delta before I bought it. Never had a problem other than all the lake scum slowing the boat down.

We keep our X on it's trailer so no worrys.

I would agree with Norbert's responses. I leave the ballast in almost all the time. I don't think there is any problem leaving the same water in all season. The water will get stinky (from the decomposition of the marine life that gets in with the water) but the stink is not a big deal.

From what I've read, some boats have a high tendency to blister as a result of too dry a layup. (not enough resin to fully wet the mat).
It seems like this is one area that Magregor does an outstanding job. Out of all the thousands of boats, I've only heard maybe one or two people mention that they experienced some blisters on their macs. And as Norbert mentioned, fresh water provides a higher osmotic driving pressure than salt water. My boat has been slipped in salt water since 98 and no blisters.

I would still epoxy barrier coat just as good practice. I bought my boat used and have no idea what bottom coating was applied previously so I simply made the first coat a good quality epoxy bottom paint.
For fresh water, I think slime along the waterline and down a few inches is the main fouling. Of course for warm salt water you need some serious antifouling paint, high copper content and ablative works well.

For freshwater racing, VC17 (or whatever it is called) is supposed to give a very smooth low drag finish. Never tried it myself.

So I have to protect the hull bottom eh. Is epoxy coating difficult or can I do it myself in the driveway? Are there alternatives I can use such as
Newglass 2
http://www.newglass2.com/cgi-bin/ccp51/ngt/cp-app.cgi
or PoliGlow a water based acrylic or polyurethane product
http://www.poliglowproducts.com/
is there an epoxy that applie as easy as the above mentioned products.
And lastly, does not a quality wax provide a barrier from water osmossis.

I've never heard of this problem before but it does have me very concerned for my expensive investment. I only moor for 3-4 months of the year and plan to haul out for bottom cleaning of growth every 4 weeks and will let it dry a couple hours.

Wax or the New Glass type products will do nothing to protect from osmosis. They will help make it easier to clean up the scum and any growth.

Many keep their boats in the water without osmosis problems, but you never know. Osmotic Blisters are the #1 problem fiberglass boats that have been kept in the water may have, and repairs can be quite expensive. The problem can occur in every fiberglass boat, big or small, no matter how much it cost. So far no one has come up with an impervious gel coat although there are some improved ones, but you won't find these products on a mac. The only way to protect from this is a Epoxy barrier coat and even that is not a perfect solution.

I wouldn't keep mine in the water without it, but since mine lives on a trailer I don't bother.

It is possible to paint the bottom of a mac while it is on the trailer. You can tilt the trailer different ways with the tounge jack to lift the boat off the trailer and onto blocks so you can paint the hard to reach areas. The painting isn't really hard, you just use a small roller. The pain is the sanding prep and getting into the tough areas where the trailer bunks are. Don't forget the inside of the dagger board trunk and the board itself.

If I was buying a new boat which I knew was going to be stored in the water I would just have the dealer supply it painted.

If you are buying a new boat and planning to slip the boat, by all means, do a bottom painting (barrier coat) and anti-fouling paint. I've experienced the worse case scenerio on my previous boat, a 32' C&C. It blistered mildly and forced my hand to have a very expensive repair done by an experieced boat yard, costing $4,000. This was an '84 C&C with several previous coats of VC17 antifouling paint, likely without barrier coat. Even after the barrier and antifouling coat were applied, together with a new epoxy bottom, I was advised that this did not rule out the possibility of future blistering. I was given a short 12 month warranty on the bottom work. It is true that the polymers and layup process of FG is improved since the days of my '84 C&C, but for the minimal investment and expense of the applying these, it's best to do it. That said, I have not done it to my new Mast 28 because I trailer slip it and want the least resistent hull surface possible. I still wonder if, like Duane, we are in jeopardy of blistering when on the 2-3 week trips??? To compound my concern, I'm in fresh water (I like the Ausie's description as "sweetwater") on the Great Lakes.
I would agree with Duane that the dealer should apply it. The barrier coat will be applied once, hopefully, in the life of the boat. You want it done well and properly. An experienced bottom painter is useful here since you want a very fair bottom. I have applied numerous VC17 bottom paint jobs and though easy, there is a right and a wrong way to do this, a bit tricky. I did some professional painting for a several summers as a college student and found this bottom painting to be a bit of a challenge, that is to get a bottom as smooth as a baby's cheek. Well, FWIW.
Jeff
I wou

I've looked into this. The bottom, centerboard well, and centerboard have to be thoroughly cleaned, a dewaxer used to remove any wax, lightly sanded, and a number of thin coats of epoxy barrier paint applied. That depends on the product, but five appears common. Then a coat of anti-fouling paint is applied.

Power Sailing Center charges $1300 on a new boat, and extra if cleaning and dewaxing is required. I'm thinking it's worth it.

--
Moe