Kevlar over fiberglass

[mike ritenour]

We maybe sailing LaVida in some hard water in the near future and would enjoy the potential of a kevlar collision mat up forward.

Inspired by our 44DS's kevlar collision layer up forward, I'm interested in putting the same on LaVida.

Is it possible to retro fit a kevlar layer onto an existing hull?

Has anyone on the board had experience laying kevlar reenforcement over or inside a fiberglass hull?

Having never messed with the stuff I'm curious if anyone else has done such a project and if so, what the job would entail.

Thanks in advance,
Rit

[Ray Garcia]

I have come to believe that nothing is impossible when it comes to working with polyester/epoxy resins. Though I believe your answer lies in your post. Your "44DS's kevlar collision layer" is just that; an embedded layer of kevlar sandwiched in between other layers of fiberglass cloth. In order to effectively gain the same benefit the kevlar would have to be layered (in this case bonded) on the inside of the hull. To add these layers against the inside of the hull would be a major undertaking. Not necessarily impossible, but it would be plenty of work. This would involve practically re-building the entire forward v-berth area. You would need access to the entire forward area of the hull to bond the new layers. After your done bonding the kevlar you would have to rebuild everything you took out to get to the hull area. Not easy, but this would take a considerable amount of time to complete.

Another thought might be to refit a watertight "collision" bulkhead. The thought being if there is a collision water would only intrude the watertight space created inside the forward portion of the hull. This could work but you would be giving up space in the v-berth area. I would imagine that the spaces immediately under the v-berth could be made completely watertight (with kevlar if you like) if the event of an underwater/waterline collision. We are talking heavy reinforcement in order for this to be effective, somewhere in the bomb shelter category. No sense having the area "burst" in a collision.

Cape Dory's with their full keel would tend to ride over a submerged object without sheering the keel. On a glancing impact there might be intrusion into the hull but I guess at that point it would depend on the object and how fast the boat is sailing. In my humble opinion I would invest in a collision mat and practice its deployment in an emergency. Collisions with objects, like airplane crashes are not common events, but when it happens, it sucks.

Mike, good question, since the same has crossed my mind and I am sure others if you sail at night and you hear a bump ("What was that?") on the hull.

Good read on "Damage Control"
http://www.caribbeancompass.com/damagecont.htm

[mike ritenour]

Thanks for your thoughts. I'd had similar thoughts and questions.

We do carry a collision mat with special hogging lines to utilize it. (However I've found it difficult to rig on certain areas of the hull and therefore have a couple of small umbrella patches onboard. Used with quick setting epoxy, they might stem the flow of a puncture.)

My main inquiry was for assistance on installing an exterior layer that would assist in ice deflection and chafe. An interior layer would possibly protect during a puncture, however the outside chafe is the more immediate problem.

Skim ice, along with the occassional bergy bit are my particular worries. I've seen skim ice eat through a fiberglass bow in no time. Hopefully, having something as tough as kevlar would help minimize the damage to the gelcoat and forestall or eliminate ice chewing through the hull.

thanks,
rit

[Tod M]

black "bras" that you see covering the front of some autos.

Hmmmm, a custom Kevlar bra for Lavida, easily removeable...

[Ray Garcia]

Well, in that case. You could, when the boat is hauled, apply a release agent to the hull in the areas you would like to protect. Mask off the other areas with tape. Build up your laminations and remove the panel. Sand, finish if you like and reinstall the protective "beard".

Two problems - 1. How do you laminate the panels without the cloth drooping off? - Vacuum bag the laminations directly to the hull.
2. All done, how do I keep it in place? You could try an adhesive, mechanical fastener or combo of both. Since this is really not a structural but protective sacrificial installation, it really would not require obviously a permanent mounting. This project would seem very possible and easy to do. There as you probably know plenty of resources available describing vacuum bagging laminations available on the internet.

Good Luck!

[mike ritenour]

MMMMMMMMMMmmmmmmmmmmm,

I'm kinda thinking of a permanent bond to the hull, vacuum bagging is surely the only way to do it.

How good of an adhesion can one get carbon fiber to fiberglass?

I'd imagine one would Skuff the gelcoat, clean the area, slather on some epoxy, lay on the kevlar, slather on the wet out and bag.

Be easier if I could turn LaVida upside down, eh

All kidding aside, I wonder how strong a bond one could create between the materials. Perhaps West Systems might hold an answer.........................

thanks,
Rit

[Steve Laume]

Kevlar skid plates are very common on white water canoes. Most WW boats are ABS plastic. It is flexy and hard to bond to. When a WW boat wears through in the bow or stern there are kits available to reinforce them with kevlar. They use a heavy mat and epoxy the whole mess right on. You then have a pretty bomb proof boat. I have never seen a kevlar skid plate wear through or come unbonded. I don't know that getting an epoxy bond to your hull would be any problem at all. If you do this project will your boat then be in a category like that of a steel or aluminium boat as far as ice is concerned. I have been to web sites that list cruising areas that would only be available to metal boats. The coast of Baffin Island comes to mind. What are your plans that call for ice protection? Then there are also those pesky shipping containers. Interesting project you have in mind, Steve.

[mike ritenour]

Well, I'm considering a companion voyage to our Newfoundland voyage of 2003.

Taking a left turn north of Newfoundland and moving up the Labrador coast until we find too much ice.

Anything I can do to put more strength in LaVida, without adding toooo much weight would be a great benefit.

I've just gotten into West System's website and its packed full of info. I think what I'm proposing is possible, I've just got to work out the kinks and i.d. the costs.

Who knows what will turn out!

sea u,
Rit

[John Danicic]

Mike:

Have you looked into coating the hull with Graphite? It has a high level of abrasion resistance. My brother put a few coats on the bottom of the dinghy I made for him and he reports that it acts like a steel skid plate. Easy to apply, just paint it on. From what I have seen, it seems to work on rocks so it should also work on ice. Worth investigating. Appling a layer of Kevlar would be expensive for a 33 foot boat hull.

Turn left at Newfoundland?? Maybe head for the Northwest Passage????

Sail on.

John Danicic
CD 36 - Mariah - #124
Lake Superior

[mike ritenour]

Well, you know me and my love of Northern sailing.

I'd be happy just to cross the Artic circle.

The graphite idea sounds interesting. Please tell me more.

I'm thinking kevlar in the bow sections and forward strike zones port and starboard and possibly the rudder. Your right, it'll cost a ton of boat credits if I go through with it.

I'll keep you posted.

sea u,
Rit

[John Danicic]

Mike:

Not sure how much more I can tell you about the stuff. Brother Paul at his adventure camp for kids, has been coating the bottom of some of his canoes to cut down on maintenance. The stuff is tough and black and I believe it is mixed with epoxy and applied in coats. It would be better for abrasion then impact. Maybe Paul can weight in here with his experience?

I intend to make a new nesting dinghy this winter using graphite on the bottom and the bulkheads so I will let you know how it goes.

I have always had the desire to turn left at Newfoundland as well not to mention Newfoundland itself. Also interested in the Ile D'Anticosti. A good book to read about that part of the world is "The boat who wouldn't float" by Farley Mowat.

Sail on.

John Danicic
CD 36 - Mariah - #124
Lake Superior

[mike ritenour]

Thanks for remembering an awesome author and book.

I'll put it on my reading list and dig it out of my library for a reread.

Yeah, I'm really looking forward to going back to NF and then on to ports North.

Looks like a couple of routes North, with Greenland having a more favorable current.

Lots of great research and reading ahead!

sea u,
rit

[The Patriot]

We maybe sailing LaVida in some hard water in the near future and would enjoy the potential of a kevlar collision mat up forward ... Inspired by our 44DS's kevlar collision layer up forward, I'm interested in putting the same on LaVida ...

You are probably familiar with Mike Arms' voyages to the Labrador and Greenland. He has sailed his 50 cutter there quite a few times. Mike is based on the Sassafras and has made many modifications to accommodate the conditions up there. If you google "Myron Arms" or "Brendans Isle" you will find a wealth of info on the topic of bullet-proofing boats for hard water. Note that Mike is quite a good fellow and will surely provide help for your inquiry.

[mike ritenour]

I've actually spoke to him many years ago, before we left on our first set of long voyages.

Really nice guy and very free with his advice.

I'll checkout his www site.

thanks,
rit

[Joe Myerson]

Mike,
Several years ago I attended a lecture by Ned Cabot, a Boston-based surgeon, now retired, who cruised to Greenland (passing through the strait that bears an ancestor's name).

He had his J-46 (I think I've got that right) specially built with several watertight collision bulkheads, a reinforced bow section and FORWARD-SCANNING SONAR. (My emphasis.)

During his talk he mentioned several times how important that sonar proved to be, as it helped him see ice at or below the surface of the water, which he said was one of the biggest dangers that he faced.

I don't know how to reach him since he's retired, but I notice he does have a blog that I found by Googling him.

You might want to contact him, or the J-Boats folks in Rhode Island. I think the forward-scanning sonar would be a handy item to have when heading north.

--Joe