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May 2 09 3:54 PM

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Wood has to breathe...

No. Wood does not breathe. It doesn't have tiny lungs, it doesn't live on air, it doesn't inhale and exhale. It can be fiberglassed, it can be encapsulated in epoxy; it will not split or expand, or crack or shrink.

What are some other marine myths that we can dispell here?

David


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greg

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#1 [url]

May 4 09 8:39 AM

Hey Eveyone! and Dave!

Myths.....give me a little time I'll come up with another one for you.....In the mean time how them cockpit/drain questions....I've got a mess.....maybe it would be best just to show some pics first.....

Myth........"crossing them cockpit drains"....






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Greg

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#2 [url]

May 4 09 11:03 AM

Greg,
 
1. Drains. Remove the sink tails. Replace them with a proper drains. Either marelon or bronze depending on the diameter that will fit. The drains should accomodate hoses as large as possible, depending on what you can fit into the openings. If you have to go with less than 1-1/2 inch hose, add two more drains at the other end of the cockpit as I did with the Bristol. If you can't fit drains into the existing recesses becasue of the diameter, I would glass over the bottom of each hole, take a hole saw and cut a large enough hole to accept the drain and shape the epoxy to the two levels of deck channels. Look to Spartan marine for some great bronze drain scuppers.
2. Drain exits. I would take them to the bottom of your boat as close to the center line as I could get. If you can't get them that close to the center line then cross them as well.
3. Cockpit engine access cover. Is this the only access to the engine? I would probbly look at sealing the hatch as much as possible. Build out the flange on the cockpit sole so it gives more of a bearing surface..I would seal it with a durable weatherstripping and screw it down every 6 inches all the way around. If the hatch cover has any flex to it it would add a layer of plywood and glass to the underside to dtrengthen it. If you need to get access to the engine via the cockpit, install an aluminum Bomar hatch into this cover so that it the large cover only needs to be removed when you are pulling the engine,
 
Does this help?
 
David
 
 

Restoring a Bristol 29 in my backyard. www.bristol29.com

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#3 [url]

May 4 09 3:55 PM

A couple of observations from your photos:
 
Yes there are definite repairs to the stern gland area of the rudder and the hose and hose clamps are much newer than the other hoses and hose clamps.
 
The aluminum backing plate for the steering pedestal is showing distinct signs of corrosion, meaning the mounting bolts are leaking and there may very well be water saturated core in the area of the bolt holes. That aluminum plate will turn to white powder if the leaks continue long enough.
 
It looks to me as if the engine hatch is leaking to some extent (the rotten bulkheads). Even without the worry of a wave filling the cockpit, that sort of constant leaking will make everything below suffer.
 
Notice the rusted condition of the cockpit drain hose clamps. Also notice the sway in the hose where water will probaby collect.
 
Do you have a spade rudder on the boat?
 
David


Restoring a Bristol 29 in my backyard. www.bristol29.com

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greg

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#4 [url]

May 5 09 9:54 AM

Dave,

THANK YOU!  You know some times you look at something so hard and so long that you make it extremely complex complicated. Thanks again for the fresh ideas! Here's a pic of the rudder, you make the call as to what type it is. Sorry for the delay had night duty at the hospital!

Greg


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Greg

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#5 [url]

May 5 09 12:03 PM

Greg,

I would call your rudder a modified skeg but for most purposes it is a spade rudder. It gets very little support from the skeg the rudder post passes thru and it has of course no lower gudgeon for support. A spade rudder generates enormous side forces on the rudder post bearing and I suspect that is the reason for the repairs shown in the picture.

Restoring a Bristol 29 in my backyard. www.bristol29.com

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greg

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#6 [url]

May 5 09 3:39 PM

Dave,

I guess you would suggest a complete removal and inspection of all the working components even though it appears that a repair has been made. I'm afraid that it's just another quick patch job that was just enough to get by on. Also did I mention that the Citation has a centerboard?

Greg

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#7 [url]

May 5 09 4:42 PM

Greg,
 
I sort of look at these add on jobs as--if I have the time and opportunity, then now rather than later. If you haven't yet gone over the rudder in detail, I for one would be concerned sailing the boat and not knowing. I would dig a hole and drop it which will make you observe and service the connection of the rudder post to the steering quadrant. I would drill some quarter inch holes in the lower area to see if I got any water out. I don't like the look of the gudgeon and would want to renew the mounting bolts and look for any corrosion, etc. Do you know what the white blob is in the photo near where the rudder post enters the skeg? Of course, with the rudder out, I would sand the entry area down to bare gelcoat and look for spyder cracks radiating out from the bearing hole. Since the entry point is at the bottom of the small skeg, I would also sand around the base of the skeg and make sure that there is no fracture cracks of it.  I would also look at the repair closely and make sure it is bonded well to the hull. I have a natural suspicion of boat yards and their work.
 
Is your hull solid or cored?

Restoring a Bristol 29 in my backyard. www.bristol29.com

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greg

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#8 [url]

May 5 09 5:31 PM

Dave,

No haven't had any of this apart yet, so I will absolutely disassemble it entirely and inspect it in detail "Most likely with your help and advice" if that's ok...The white blob is a piece of bottom paint that I probably popped loose...the hull is not cored it's solid,  I haven't taken any thru-hulls out yet to see what the thickness is, I'll see if I can check that out tomorrow and let you know.

Greg

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greg

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#10 [url]

May 6 09 8:53 AM

Dave,

Here's a couple if pics of the hull and thickness shot.  1/4 thick   I scraped away some areas of the bottom paint just to take a look to see if I could find any blisters.....Everything seems to be fine, I couldn't find any areas that were bubbled or that oozed liquid. I felt like at least I had a project that had a solid foundation to work with. However with your eye you may point out something I'm not aware of.

Greg


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May 6 09 11:43 AM


Hey Greg,

Thanks for the pictures--they always help. The bottom looks good and I think will be easy to prepare for new paint. The rudder looks ok barring any issues with water saturation or metal degradation. I am puzzled by the last photo, showing I think the exhaust outlet, with no thru-hull, simply what looks like a fiberglass tube bonded to the hole?? I would definitely end that and install a proper exhaust outlet or thru-hull.

Defender sells a very robust fiberglass exhaust thru-hull made by Varney in various diameters. I use one on the Bristol:

http://www.defender.com/product.jsp?path=-1|51|106370|292325|314570&id=57552



I appreciate the kind words about the new forum. 


Restoring a Bristol 29 in my backyard. www.bristol29.com

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#15 [url]

Jun 16 09 12:35 PM





More marine myths:
Bronze is somehow ‘corrosion proof” in seawater. As I have explained elsewhere in the forum, bronze isn’t just bronze. It can be a casting of a number of different metals, each with a different nobility and those different nobilities cause the metal itself to generate galvanic corrosion. Bronze often has high levels of zinc, and that fact alone causes it to self destruct in an electrolyte of seawater. There is no numerical rating system for bronze, and in fact bronze is called by so many different names it is questionable what it contains (need I mention China-made pet food and drywall?). So buyer and sailor beware.
Fiberglass has to “breathe”.  I suppose when fiberglass develops blisters it is because its little lungs are filling up with water, right? No fiberglass doesn’t breathe, and can and should be encapsulated in epoxy as a permanent means of stability. Fiberglass on both old and new boats is often laid up too dry and literally contains un-wetted out fiberglass cloth in its layups, which can attract and hold moisture and of course does nothing for strength. Fiberglass can also contain voids that can contribute to porosity. Finally, some boats were and still are built using a chopper gun for some areas of the structure (Halberg Rassy’s for instance use chopper guns to build the entire hull). Fiberglass molded with a chopper gun makes the weakest hulls of all and can definitely use the epoxy as a means of fortification.
The best substrate for a primer / LPU finish on decks and hulls is two or more layers of unthickened epoxy, sanded smooth. Likewise, the best finish for the interior of your hull is unthickened epoxy colored with a white or gray pigment. The coating completely seals and strengthens the hull, making a permanent painted finish to the bilge and lockers of your boat, yet you can bond to it with epoxy and fiberglass cloth at any time without having to sand off paint.


Stainless steel will always suffer from crevice corrosion in a sea water environment. Related myths include:



            Stainless steel always rusts—it just stains less (get it?) than mild steel.
            Stainless steel turnbuckles will always suffer from galling and failure.
            Similar: stainless steel fasteners will always gall.
            Stainless steel has to “breathe” (can’t forget about its tiny lungs).
Crevice corrosion in 302 and 304 stainless steel is caused by a lack of oxygen in stagnant salt water. In that environment, an ionic transfer takes place and the results can cause crevices to form in the steel, eventually breaking under load. 316 stainless is much less susceptible to crevice corrosion The bottom line is, underwater metal unless it is Monel needs to be inspected like everything on your boat.
Staining. Yes stainless steel will stain, but it does not rust and the staining can be instaly removed with a little Comet or similar detergent.
Turnbuckles. Like every kind of marine gear there are turnbuckles and then there are turnbuckles. There is a lot of crap made in now—regardless of whether it is bronze or stainless I would not risk my rig with it. There are high quality stainless turnbuckles: I have them on my boat and they don’t gall or corrode or deteriorate. Galling has a lot to do with how the threads are cut and if friction is added, heat is added, galling can occur. I have had it start to occur treading stainless bolts into holes tapped in epoxy. The bottom line is to use quality stainless, fasteners and turnbuckles and you won’t have a problem with galling.
Fiberglass hulls have to flex and bend or they will shatter.  Boat owners espouse this who own boats that are built with a thin layup schedule, or are structurally just not stiff. However, fiberglass boats can and should be just as stout and inflexible as wood, alumimum or steel boats. Anyone who says fiberglass boats show flex has never sailed a Westsail 32, a Morris Yacht, a Bristol Yacht, a Hinckley Yacht, a Pacific Seacraft, a Southern Cross, a Hans Christian, a Shannon Yacht, an Ocean Cruising Yacht, a Cherubini, a Camper and Nicholson, a Sam Morse BCC, a Little Harbor, a Swan …the list goes on and on. All extremely stiff boats that do not flex, bend, twist, bow, or shatter.
Epoxy is not waterproof. Blame Larry Pardy for this one. For some reason he has a hard-on about epoxy—I think because he had some glue failures in the cabin sides of his boat and blamed the glue instead of user error. Epoxy is waterproof for all intents and purposes if used correctly and the surface is prepared correctly.
That means the epoxy must be mixed correctly and completely.
It means it has to be used at full strength without thinning it with some chemical and it has to be used in the proper temperature range.
It means it cannot be applied over paint, or “red lead” or any other coating that prevents it from saturating the wood fibers.
It means you have to wipe the surfaces first with acetone to remove any oils or impurities.
It means planks have to be clamped according to the Gudgeon Brothers instructions.
It means you have to apply enough coats of epoxy—West Systems recommends a minimum of two. I stick to a minimum of three. And it has to be protected from UV, either with paint or with a clear coating that contains UV filters.
It means if you are using epoxy on brightwork, it should surround the wood encapsulating it so there are no edges of epoxy where bare wood can be exposed to moisture.










Restoring a Bristol 29 in my backyard. www.bristol29.com

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greg

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#16 [url]

Jun 16 09 7:47 PM

Dave,

    Really......paint the deck or cabin with tinted white epoxy.......then the LPU for the UV protection....what about just sticking to the silvertip yacht primer and then the LPU...

Greg

Greg

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#17 [url]

Jun 17 09 6:27 AM

Greg,

Sorry if I was confusing about that. The silvertip high build primer should be used under the LPU although System Three says their water reducable LPU can be used over either their high build epoxy primer or epoxy, I suggest sealing gelcoat prior to applying the primer because it provies a very nice clean way of filling any pin holes or irregularities in the surface.

Restoring a Bristol 29 in my backyard. www.bristol29.com

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greg

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#19 [url]

Jun 17 09 7:33 PM

Dave,

The Hatch combing is a real problem for me...it would take a bunch of 403 to fill the entire area...do you have any other ideas?? I know I can create a bevel on the deck side without any problem, but on the hatch side my options are limited. I could use the 403 to build out from the hatch sides enough to create a section to bond to with some glass, but I wonder if it would be strong enough..

Greg

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#20 [url]

Jun 17 09 8:05 PM

Greg,

From the photos I concluded that the combing was already in place and you were filling between the combing and the edge of the deck. Am I not seeing what you need to do? Can you send some pictures with a ruler in place so I can understand the relative sizes?

Thanks!

Restoring a Bristol 29 in my backyard. www.bristol29.com

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