New life for old wood boats

I thought this subject warranted its own thread, as there are some (wild eyed & crazy) people on TF who love and want to take on the ownership of old wooden hulled boats.

swampu posted this:
Trawler Forum - View Single Post - Argonaught II


The following is from the Sintes Fiberglass Designs C-Flex sheathing system website;

Each "plank" of C-Flex contains small semi-rigid rods that run lengthwise throughout the cloth. These rods allow the fiberglass to hold its form while resin is applied. This process eliminates the need for a full mold used in traditional fiberglass construction. The basic technique involves both chemically bonding and mechanically fastening the C-Flex to the wooden hull. The C-Flex is applied vertically from gunwale to keel so that the rods in the C-Flex run perpendicular to the wooden planking. The mechanical fastening is accomplished with heavy staples, and the chemical is done with an elastomeric adhesive.

The C-Flex is then saturated with resin and covered with chopped strand mat (CSM). A fairing compound is applied to the exterior, and the compound is sanded and painted.

First is that it bonds ferociously to both the C-Flex and the wooden planking. Secondly, it will bond to wet wood, treated wood, and virtually all the various types of woods used in marine planking. Add thirdly, being an elastomeric, it will stretch (300%) and compress without breaking its bond. This is essential in preventing the delamination, which might otherwise be caused by the expansion and contraction of the planking and by the “working” of the hull.

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Here's a video of the procedure, the difference being that on an old wooden vessel the hull wouldn't be flipped and the C-Flex would be put on in vertical strips from gunnel to keel;


Nova Trawlers of Nova Scotia also take on and give life to old wooden hulled fishing vessels;

The* Boat* Business* Group

What be your thoughts?

Greetings,
Mr. MM. I like wooden boats both old and new. We had custodianship of a 34' Christ Craft for 12 years. In some ways, MUCH nicer than FRP (ride and ease of board replacement/repair to name 2) BUT, and there's always a but, one cannot be a procrastinator with a wooden boat. You have to be VERY proactive with your maintenance and address leaks and paint/coating issues properly and promptly or the dreaded rot will set in.

As far as "sheathing" wood with anything, I'm of the opinion that it is a stopgap measure at best. Yes, some owners have achieved success and continue to enjoy their vessels as a result of "sheathing" but I suspect they are in the small minority and given the $$ Mr. s mentioned to have his boat done, evidently properly, most "sheathers" only exacerbate existing rot problems by going the cheap route.

Wooden boats seem to fair much better in salt water than in fresh due to the pickling effect of the salt.

I watched the video and it may have been recorded about the same time the Rose was getting the C-flex. I did not own the boat at that time it was done, but the po talked to me about the process and it was very in depth. The boat has been in the water almost 50 years since this process and there is no rot. It actually insures as a fiberglass boat because of the process. I will be putting her in the yard early summer and should have some good bottom shots and the opportunity to check it out. I recently installed a float switch on the bilge pump but before that I would only turn the bilge on about once a month, all of that water cam thru a few leaks in the deck. She's tight!

swampu said:

...The boat has been in the water almost 50 years since this process and there is no rot. It actually insures as a fiberglass boat because of the process...

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Good to know

Looking forward to your report after hauling this summer.

Found Seeman Composites, the manufacturer of C-Flex;

C-Flex

...and their C-Flex manual in PDF format;

http://seemanncomposites.com/images/seemann/cflex001.pdf

Seemann is located about 5 miles from the house. I wonder if the rose was a early candidate for this system?

C-flex as far as I know has been around for over 40 years....


Never actually saw a boat with it..... so hard to comment on it.


But if it was a great idea and easy to do, I think I would have come across one in all these years of being in and out of boatyards.


The Rose is the first I have actually heard of C-flex from the owner.

psneeld said:

C-flex as far as I know has been around for over 40 years....


Never actually saw a boat with it..... so hard to comment on it.


But if it was a great idea and easy to do, I think I would have come across one in all these years of being in and out of boatyards.


The Rose is the first I have actually heard of C-flex from the owner.

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Might be that it hasn't received much in the way of marketing energies...judging by their list of customers, they've bellied up to some fairly deep troughs;

• U.S. Naval Warfare Center Carderock Division
• U.S. Naval Undersea Warfare Center
• U.S. Army Tank-Automotive and Armaments Command
• Materials Sciences Corporation
• National Aeronautics and Space Administration
• Northrop Grumman Electronic Systems
• Northrop Grumman Ship Systems
• Northrop Grumman Newport News
• Boeing
• General Dynamics Land Systems
• Lockheed Martin
• Bath Iron Works
• Textron Marine and Land Systems
• Raytheon

Looks like a great product....just haven't seen it in our arena yet.

Apparently Bill Seemann's energies went toward developing and patenting a resin infusion process;

The use of the resin infusion process has grown significantly in the 25 years since fiberglass boatbuilder/composite materials distributor Seemann Composites (Gulfport, Miss.) introduced SCRIMP (Seemann Composites Resin Infusion Molding Process). Closed molding in boat decks, for example, grew from 5 percent in 2000 to between 20 and 50 percent by 2005, according to Materials in Marine, a study published by JEC Group (Paris, France) in 2006. The same study predicted that by 2015, closed molding would be used for more than 60 percent of marine composites (see Fig. 1). The process has evolved with equal vigor, as evidenced by the many other acronyms and patents that followed SCRIMP since 1987...

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The evolution of infusion : CompositesWorld

Read on another forum that he recently sold the patent...maybe swampu could stroll on over to sniff around a bit to see if he's going to go back and tweak C-Flex?

Interesting thread for a guy like me. I have seen the results of this type of work. I have seen older fish boats with chicken wire stapled over the hull and ferro cement over. Who knew.

But something thats is not mentioned within these threads is the type of wood boat or type of wood hull design, material etc etc. The condition of the vessel inside and out.

As an example the pics are of a recent project using the technique. From my history , experience , this old CC was the wrong platform. Being a well used sea skiff , of plywood construction. I mean you are attaching to the layers of the ply. The boat is going to be a nightmare down the road, its a light build. Its not a stiff boat. The guys also spent a ton of cash fitting her out with lots of new electronics, but the interior of the wood shows some not such great signs of " wear " http://www.trawlerforum.com/forums/images/trawler/smilies/sk/banghead.gif

Just something to keep in mind. A wood boat is just not a wood boat, there are way too many build techniques , materials to be covered by one process.

Just my two cents.

RT Firefly said:

Greetings,
Mr. MM. I like wooden boats both old and new. We had custodianship of a 34' Christ Craft for 12 years. In some ways, MUCH nicer than FRP (ride and ease of board replacement/repair to name 2) BUT, and there's always a but, one cannot be a procrastinator with a wooden boat. You have to be VERY proactive with your maintenance and address leaks and paint/coating issues properly and promptly or the dreaded rot will set in.

As far as "sheathing" wood with anything, I'm of the opinion that it is a stopgap measure at best. Yes, some owners have achieved success and continue to enjoy their vessels as a result of "sheathing" but I suspect they are in the small minority and given the $$ Mr. s mentioned to have his boat done, evidently properly, most "sheathers" only exacerbate existing rot problems by going the cheap route.


Wooden boats seem to fair much better in salt water than in fresh due to the pickling effect of the salt.

Click to expand...

RT,
I agree completely. However copper sheathing may be an exception.
As far as I know C-Flex was intended for one off builds for the home builder and marketed for years by GlennL (I think) so the intended use has changed it seems. Laminating FG to wood hulls makes the boat much harder to repair and time will delamiate anything. Perhaps it's done at times to put off re-fastening thinking it will (strength wise) to a degree take the place of fasteners.
Personally I would coat a wood hull only w paint.

If this comes through, our 1936 Poulsbo Skiff that has been fiber glassed over. It was done about 30 years ago. Happy to report that ALL the wood that was in place then is in place now and no deterioration of the wood or movement of the glass has occurred. If there was one step not accomplished due to that step being a later thought, was to staple the glass fabric to the wood with stainless staples prior to applying the coatings. Never the less, nothing resulted for not doing so
Al-Ketchikan 27'Marben Pocket CRUISER

DIDN'T ATTACH= SORRY

Still sniffing around that Internet thingy and found these guys who say they have C-Flexed 99 boats and counting...Sajwaj Fiberglass Specialties;

Sajwaj Fiberglass Specialties - C-Flex Sheating, Custom Boat Construction, Mississippi Gulfcoast,

...and a photo of one partly done;

Cool picture. Maybe c-flex never made it out of Mississippi.

Polyurea Coatings - Page 3 - Boat Design Forums

Polyurea coating, seals out water, adds tremendous strength.
Will grip wood and concrete, wont stick well to shiny gelcoat, but will stick well to roughened fiberglass.


If you used dragonshield, hull becomes bullet proof.
K5™ Polyurea Phantom Jet Boat Hull Protection

sdowney717 said:

Polyurea Coatings - Page 3 - Boat Design Forums

Polyurea coating, seals out water, adds tremendous strength.
Will grip wood and concrete, wont stick well to shiny gelcoat, but will stick well to roughened fiberglass.

If you used dragonshield, hull becomes bullet proof.
K5™ Polyurea Phantom Jet Boat Hull Protection

Click to expand...

Gnarly!

MurrayM said:

Gnarly!

Click to expand...

The blast test showing it prevent penetration to me means a boat hull coated with Dragon Shield would not be penetrated easily if it whacked into something, would stay dry.

sdowney717...are you planning to use dragon shield if your Sani-Tred Permaflex ever degrades? How is it holding up? Does it stop bottom growth as good as they claim from their dock piling test? (Looks like you had a flourishing community going on your bottom before you coated your hull!!!!)

Trawler Forum - View Single Post - Electrolysis check for Swift Trawler Owners

PermaFlex Waterproofing Coating Description

Boat Deck Paint & Sealant for Fresh & Salt Water -

MurrayM said:

sdowney717...are you planning to use dragon shield if your Sani-Tred Permaflex ever degrades? How is it holding up? Does it stop bottom growth as good as they claim from their dock piling test? (Looks like you had a flourishing community going on your bottom before you coated your hull!!!!)

Trawler Forum - View Single Post - Electrolysis check for Swift Trawler Owners

PermaFlex Waterproofing Coating Description

Boat Deck Paint & Sealant for Fresh & Salt Water -

Click to expand...

I do like that polyurea a lot, except that I think you have to get someone to do it for you and I am a DIY type person. It is a spray on product, it seems to have amazing properties and is not heavy.

Ok on the Sani-Tred, It is a very slippery slick shiny hard rubber like coating.
If you have a fast boat, and water flow, and your using the boat a lot, I can imagine everything slips right off. I remember for the first 6 months, my hand easily swiped off even small barnacles growing on the hull.

Permaflex, marine growth it will not stop. That flourishing growth was growing on the Sani Tred permaflex. Really it was a test for me, I put the boat in without any bottom paint.

One thing is you must wash off between coats with dish soap and spray clean with water. Permaflex makes an oil as it cures and that oil will hurt adhesion of the next coat. Another issue is upside down, it will form runs and drips, which I don't think you can do much about it.
When I repaired my hull, I pulled planks and repaired the frames and also coated the inside as well as the outside.
Here are some pics.
Regarding the shaft log area. I lined the hole with electrical grey non metallic conduit, glued in with Black PL Polyurethane roof and flashing and Sikaflex, some kind of runny liquid concrete repair product to seal this area.
All of this held up very well. Except it was not adhering well to the keel after 5 years. So I peeled it off and coated with Loctite Black PL roof and flashing polyurethane. I had done a 5 year submersion test on this hull with it in some spots and they were fine.

The last photo shows the Loctite Black PL. It is sold in 10 oz cartridge tubes at the Home Depot. I am very impressed with it.It is similar to 5200, but softer, has more yield.

Before I coated Permaflex, I cleaned out all the seams and used a 50-50 mix of sawdust and Loctite PL premium polyurethane construction adhesive. It is an excellent filler for wood, waterproof and will not come out of the seams. My hull is completely leak free and dry. It will swell up as it cures, so I press it back down using a plastic cereal bag, or a putty knife.

Here in 2014 after the 2006 repair, I coated the keel in Black PL
You still see the sanded Permaflex is well stuck to the main hull, however it did not stick to my oak keel. My keel the wood is somewhat blackened and charred in appearance, so the wood surface may have just not been clean enough. However the Black PL S30 smeared on with a 6 inch trowel is just like frosting a cake and totally waterproof. And it seems to have adhered well to the keel.
If you mix 1/32 inch fiberglass milled fibers 30% to Black PL 70%, you get a real tough rubber membrane. I did that on the bow in 2014 going back 10 feet as an experiment, and have been very happy with it.
It is very easy to use and apply. The keel I did not put in the fibers. I do like it mixed with fibers. Someday I might recoat the entire hull in Black PL and the 1/32 milled fibers. But mostly I like to experiment, not that it needs that.

I also discovered to seal up big cracks in keels, as in where the wood beams intersect, you mix Black PL saturated into white cotton balls and stuff it into the seams. It seals it, works great. See a wood boat is going to want to move, and these type sealers I use will move with the wood. Black PL when mixed with milled fibers reminds me of car tire rubber.

sdowney717 said:

But mostly I like to experiment...

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No kidding! Not much of a herd follower, are you

Thanks for the tips, and your ongoing experimentation.