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Here are all the (relevant) E-Mails related to the question of plastic verses composite boats. Thanks to everyone who contributed to the discussion. In some cases people got a little off subject and used this discussion as an opportunity to rant on unrelated issues. If the ranting included something useful to this discussion, I included them on this page anyway. Enjoy:

 

As the owner of the most recently damaged boat I have been asking myself the same question.  I am not 100% convinced that heavier is always better since two of the three boats were of heavier glass construction than some of the other New World designs.  I can only speak from my experience and observations.

1.    Kevlar is used because it is lighter than fiberglass and somewhat more flexible--it doesn't shatter as easily. 

2.    The manufacturers use less Kevlar than fiberglass for the same amount of strength thereby decreasing weight and slightly increasing flexibility but not overall strength.

3.    The design of my boat, a Tesla NM, has a relatively flat deck which absorbed all the force of impact.  The increased rigidity of the sides caused by the heavy plastic vertical adjusting plates of the SmartTrack rudder system pedals and the longitudinal stiffener in the hull prevented the boat from folding.

Besides not being where I was what could I have done to avoid the damage:

I could have rolled and let the impact fall on the slight V'd hull thereby lessening the force of impact.  I thought of this momentarily with the following conclusion:  While the water was deep enough to roll several moments before the heavy hydraulics made the depth unknown.  I could have been  pushed down into the sand and snapped my neck.  I could have been parallel to the breaker and rolled under the crest.  Insufficient time to maneuver. 

What, if anything could have prevented the damage under the conditions:  A peaked design to the deck, heavier lay-up giving greater compression strength, some type to internal stiffener inside the cockpit. 

Is the answer plastic?  I am not 100% convinced.  On a recent trip to Mexico one of the plastic boats oil canned the bottom, permanently.  I have seen plastic break and shatter.  I don't know if a plastic boat, of same design, would have not had even worse damage due to lack of flexibility.  Plastic is more sensitive to temperature changes.  Glass and Kevlar, at least the gel coat finishes, produce a boat the travels through the water faster than plastic of same design.

Believe me I have given lots of thought to deck design.  I have demo'd quite a few boats and I still consider the Tesla a boat I can "feel at one with."  I think if the Kevlar lay-up was as heavy as the glass lay-up on my other boat it would not have broken.

Just some thoughts—

Mike Brown

 

Everyone,

 I think a lot of composite kayaks are built with a lay-up that is too light, one of my kayaks, an Arctic Hawk, being a good example. It is a bit flimsy, but so far it hasn't been damaged when playing in the surf. My Ellesmere has some core mat in the hull and deck for stiffening, and I can even stand on the front deck without damaging it. One of the problems with a lot of kevlar kayaks is that material flexes too much. Kevlar won't rip but it is not very stiff at all. That's why most expedition lay-ups have kevlar and fiberglass and end up weighing as much as a regular lay-up. On one hand I want a strong kayak, but on the other, I want it to be easy to carry, so it is a little of give and take. I guess that we just have to use our skills the best we can to avoid those occasional situations when our composite kayaks can be damaged. The Inuit couldn't just go around and bang their skinboats into icebergs all the time either.

 Duane

 

As a person who occasionally contributes to the "carnage" I feel that my mishaps are not only okay, but good in a sense.  I'm a beginner who started kayaking in September.

I've paddled in easy conditions, taken the two day "intensive weekend" for Southwind Kayaks and joined in many of the CKF coastal paddles since.  In most sports I've done I've found that it is best if any day is mostly just under to at my ability, but with a little that is just past.  The trick is to push the limits while avoiding injury or spending all my time in rescue mode.  So having an average of one capsize for every two outings is about right for me (more capsizing when I'm purposely trying to work on surf skills).  Most of my capsizes are nothing worse than a minor hassle and at times actually fun (I have a plastic boat so I'm not so concerned about boat damage).

So when I hear of a trip suitable for "advanced beginners" I carefully monitor the surf reports and then join in if I think I won't get hurt or spend too much time upside down.

So other beginners too may be encouraged to join these trips.  They too may contribute to the "carnage".  As long as it is kept within limits that people accept then these beginners will soon be more skilled.

If there are better ways to advance without also spending time capsizing I'm all ears.  Otherwise I'll continue having fun getting wet every now and then.

--John

 

My 2 cents

I think we should keep a grasp on the potentially more severe problem; that of someday somebody getting severely injured while crashing in the waves. Like a broken neck or head.  With the number of yakkers severely dumping lately, the pessimistic prediction is that it is just a matter of time until it happens.  We know there is potentially a very large force of tons of water upon a rigid boat surface, and with sand and rocks being involved, against a frail human inside or underneath. The kayak is a dangerous object to avoid being near when spilling in the surf, I postulate. OK, easy to say and a lot of people have fun with the risk and excitement of being in the surf. And they will say it is worth the danger. So what then? Perhaps think of a kayak surf spill with human inside to be unacceptable, and to avoid it at all costs. We can, say, launch only in harbors or tiny waves, but to allow to launch in typical conditions (relatively rough water), then one must read the waves well, launch as fast and strongly as humanly possible, and be able to bail out and get away from the kayak as fast as possible if needed, I believe.

I mention here my way of doing it.  I hold my kayak steady in thigh deep water (even lifting it above the waves), then waiting until the right instant of relative calmness of waves, I jump in and paddle like mad until I am in deeper safe water. Typically we are talking about 10 seconds to jump in and do intense windmill paddling -- less than the wave period of large waves. I leave my legs out of the kayak sticking out forward during that time because I can't afford the seconds to put then inside. I do not have time, either, to attach the spray skirt. If I have to plow into some whitewater, yes, some gets in. When landing the procedure is similar: fast, be ready, jump out and hand hold the yak among the waves when almost on the beach (I do leave my legs inside, but skirt pulled, when coming in). How I find the right instant between the waves, I can say a lot more sometime to those who may be interested.

The advantage, of this, I say, is that I am ready to bail very fast if I am about to get creamed or dumped in a big wave or even a small one. I jump out on the safer side of the boat and if needed, dive down away from the boat. Admittedly or fortunately I have not had to do this yet in a big crasher. I have when almost on the shore coming in; the boat dumped over (but not with me in it). I look at an emergency exit in something big as abandoning the boat (but not me), to the tons of water, sand, rock etc. Maybe a permanent loss of the yak but not me.

Maybe this procedure is not as feasible with a very sleek and narrow yak. Mine is 24 inches wide and not with not a very upcurved bow. And I am sure there are other factors I have not mentioned. It is probably an oddball way of launching. Nobody else seems to do it this way. Thoughts and comments?  Is it really acceptable to crash in dangerous surf while inside?  Why is the method of lingering in the shallows with hand on bottom at first the only(?) one taught?  Note - I think I am less easily damaged by criticism then Kevlar boats are by surf.

Ron Hudson

 

Ron and All,

 I never launch or land in any surf, big or small, with my sprayskirt unattached or my legs hanging out. With my leg inside and my skirt on, I can brace and keep water out if a wave hits me. With your legs hanging out, you can't brace very well, and with a boat full of water after punching a wave with the skirt off, your stability is going to be low and you will probably need to brace. When you can't brace very well, you are probably going swimming, and your kayak with a flooded cockpit is going to be tossed around and rolled on the beach by the waves, a situation in which it is very vulnerable to damage. On a landing with the skirt off, water can get in the kayak if a wave hits you, which is likely, and your kayak will be much heavier, making it more vulnerable to damage if you hit a rock and harder to drag up to safety away from the waves after you get out.

 Duane

 

 

I recently found a nice glossary of composite materials in Paddler magazine I thought I'd pass along. I've never known there are different types of glass boats and found this interesting.

v     E-Glass: Resistant to compression and abrasion.  Not especially strong under tension and can be heavy due to high absorption of resign.  Often used in the outer layers of composites.

v     S-Glass: High performance fiberglass cloth.  Abrasion resistant with a greater tensile strength (resistant to longitudinal stress) than E-glass.  Also used in outter layers.

v     Kevlar:  Synthetic fiber with resistance to tension and shock, not especially resistant to compression and abrasion.  Used in bulletproof vests and auto racing helmets, also on inner layers and complete constructions of boats.

v     Carbon Fiber:  A rigid fiber with high tensile strength. Used as a stiffening layer or for reinforcement.

Jon

 

 Steve

When I ordered my Express last March I mentioned to Matt Broze at Mariners Kayaks that I planned on keeping my Looksha Sport because it would be better for rock gardening.  He went on in elaborate detail why that was not the case.  He seemed exasperated by the endurance of what he considers the plastic myth. 

I feel unqualified to wade in on the subject but offer this just to point out that many serious kayakers do not consider plastic a superior rock garden boat.  I'm pretty sure you would get a pretty good argument on the BASK list from kayakers used to conditions more extreme than  we are accustomed to down here.

A great subject.  Thanks for initiating the discussion.

Read Shoemaker

 

Wow! This is an interesting question. I wonder, however, if you really want to hear the answer? You preface this question as asking for opinions, so please bear in mind that this is mine, for whatever it's worth.

I believe that virtually every major kayaking expedition has been performed with a composite boat. I think that pretty much says it all. I paddled the same composite boat for some fifteen years or so, doing trips in Canada and Baja, and all parts in-between. If you ask anybody who has ever spent time paddling with me (or who saw my boat before it was stolen) they will probably testify to the fact that I used that boat for everything it was worth -- and then some! Or to put it bluntly, I beat the crap out of it. Yet with what I consider to be fairly minor maintenance I was able to depend on that boat to do everything I asked of it without reservation.

I have seen composite boats that were heavily damaged. I have also seen plastic boats that were heavily damaged. The big difference between the two is that while the damaged composite boats were repairable, the plastic boats were trashed. Certainly, the ratio of damaged composite boats is higher then that of the plastic ones. Polyethylene is tough stuff. However, considering that a heavily damaged plastic boat is pretty much the end of that boat, I would still have to say that the composite boats generally fare much better, in the long run, then do the plastic. Remember, this is just my opinion based on my own personal experiences.

Which brings us to the question of just what are you people doing to cause all of this damage to your boats in the first place? Is the strength of the boats really the issue here? I think it might be worth noting that while I receive and read countless kayaking trip reports from around the world, your group is the only one that seems to regularly include a number of capsizes and boat damage. Why is that? Is it that you folks are the only group out there that is really testing it's limits? It seems to me that not very long ago there was a discussion about the actual level of your day trips in which all of your "leaders" claimed the trips to be suitable for beginners.

I had the enlightening pleasure to join you guys on the day after Thanksgiving paddle at Palos Verde. While I considered the conditions to be rather benign and did not have even the slightest problem launching or landing, there were nevertheless a few capsizes in the group. During one landing when I very politely tried to offer some constructive criticism about the way things were being done I was surprised to have my advice quickly shrugged away with the comment, "different people do things in different ways."

So what's the problem here? I'm asking you?

Scott

 

Thanks for your comments Scott. You have brought out an interesting point not related to the original question so I'll comment early.

I wasn't the organizer of the Day after T day paddle. Mike and Duane were. There were several capsizes in the surf zone, which seems to be the norm from what I read in our SoCal trip reports. It happens. My recollection from reading many Sea Kayaker magazine trip reports is that capsizes in breaking water seem to be a common occurrence among all levels of paddlers. The only difference may be the size of the waves, or whether it ends in a swim or a roll. Anyway, that was a fun paddle that I though went quite well, especially considering the extremely wide range of skills and experience of the group.

Since you refer to "your group", I am assuming that you are relating the day after T day paddle with our usual PV rock garden paddles. There is no similarity.

While you were enjoying "benign" conditions, there was a lot of excitement (and some danger) to be experienced in the rocks just a few meters away. This should not be confused with just launching or landing in rocks with that as your goal. Any experienced paddle should know how to do that without mayhem. Rock gardening is deliberately making fun out of wash-overs, surge channels, caldrons, etc.  So, I would describe rock gardening as a cross between surfing and white water paddling, either of which is likely to result in capsizes. 

Some time ago, a very well known paddler, instructor, well known author, made a to-do about truly skilled paddlers being able to rock garden without touching a rock. I was skeptical, but open to seeing it done. I have to say that watching this man paddle was a thing of beauty. His boat control is more than I ever hope to accomplish. Nevertheless, he had his boat hung up in the rocks after only a few minutes of very low intensity rock gardening.

So, composite boats are just out of the question for serious rock play, unless repairing boats is part of your hobby. My question about the suitability of composite boats is really related to open ocean paddling only, which, I suppose, should include launching and landing in rocks, but not playing in them.

             Steve Brown

 

Steve,
Many manufacturers recognize the problems you have noted, and offer special "Expedition" lay-ups (for extra $$) for their composite boats, involving extra layers of glass/Kevlar on the keel, hull or hull and top. Ask Dublin Dave about his extra strong Kajak Sport boat. However, the kind of landings your group was practicing are usually avoided on expeditions unless absolutely necessary, and most paddlers prefer not to risk their boats unless it is unavoidable.

Margo


Like I said in a previous post, not all composite boats are created equally. I chose a Necky Arluk II because I believed it to be one of the best made composite boats on the market. I made perhaps a dozen trips over to the Channel Islands in that boat during which I spent countless hours playing in the rocks. Twice I crushed my compass mount on the forward deck of my boat when it got pinned against the ceiling of a small cave by the rising water. Each time I managed to find a higher part of the ceiling to tuck my body into so that I could escape injury. I would regularly do seal landings and launches in that boat off of the rocks. And I would launch off of rocky beaches by getting into the boat and sliding down the rocks into the water right along side with the guys in the plastic boats. And let us not forget that the Tsunami Rangers, those wacky rock garden kinda guys, seem to prefer composite boats for their escapades as well.

While I do agree with you that plastic is probably a better choice for the average paddler who wants to play in the rocks, I would be somewhat reluctant to declare composite boats unsuitable for such tasks.

Scott


OK, let me try this one more time. The original question was "are composite boats really up to the rigors of open ocean paddling, including launching and landing in moderately large surf?" Apparently I was not very clear in the point I was trying to make as many of you seem to think I was bashing the CKF events. I don't think I was, but if it came out that way I apologize.

Let's try this one:

If a sixteen year old kid with a learners permit crashes a Ferrari into a brick wall are you going to blame the damage to the vehicle on the inherent weakness' of that particular type of car, or on the poor judgment and/or lack of experience of the driver?

Do you see where I'm going here? There are certainly some cheaply made composite boats on the market, just as there are some really well made ones. Regardless, if you put the boat in the right situation you can damage it. If someone would like to contribute their plastic boat for a little experiment I feel fairly certain that if I were allowed to take it out for a day on the water I could destroy it. This wouldn't really prove anything, but I would certainly enjoy the experience :-) Plastic may give you a little more leeway in rough conditions. But I would not be too quick to discount composite boats for being up to the task either. Composite boats are infinitely repairable. You can't say that about the plastic ones. Which type of boat would you rather have on a trip to some remote location? One you can fix if it gets damaged, or one you can't?

Scott

 

And to that I might add what's the use in building a pretty but delicate wood boat? They aren't much cheaper in the end than composite boats, add the emotional attachment that can't help but occur after so many hours invested and well, I'll stick to Tupperware for play and Kevlar for distance. (haven't done the distance thing for quite a while though.) I have to admit I get nervous every time I hear talk of building boats cause I know nobody will want to "adventure paddle" for fear of boat damage.

Jack

 

PS: have you seen how bashed up my Kevlar Looksha 2 is?

PPS: I think a big contributing factor to the carnage is the combination of high tide and steep beach. My shoulder problems began 8 years ago when out of ignorance I was playing in that combination, got sucked out to the foot of a dumper, left momentarily dry and side ways, dumped on, picked up, turned up side down

and driven inverted into the sand. I landed on my shoulder and neck. The work fall of course did the

big damage but that was my first injury. I hear Don got trashed in the same combination just a few weeks ago and now this trip report says the same. I think unless you are lucky and or a surf god, its the worst conditions for composite boats. I can think of no bigger threat to composite

other than adding rocks to the combination of high tide and steep beach. Just my opinion though.

 

Hi Scott:

Read your comments with interest.

I agree with your comments on plastic vs. composite boats. I would also add the weight and speed factor.  My kevlar boat is considerably easier to heft and is faster than the average plastic boat.  The kevlar is tougher than fiberglass, as well.  I was able to get a major bash repaired back to nearly original condition, although kevlar is harder to work with than fiberglass.

As to your comments about capsizes, etc.......  I think that you are excessively generalizing.  Some of the capsizes reported are simply launchings and landings on day touring trips in sea kayaks. I personally think that there are excessive capsizes on some of those trips. I also know that there were tricky dumping waves on the recent trips reported, also. I observed some of those that were just bad luck or bad timing.   Some were due to inexperience. Having been on hundreds of trips, I have seen many dozens of capsizes. 

As to the day after Thanksgiving trip, I had zero problems also.  I feel that the less experienced folks should have timed them better or ridden in behind the crests.  Dumping waves are much less forgiving than spilling ones.  But if you were going to experiment with dumping waves, that was  a good day, since they weren't of lethal size. One guy who did a particularly spectacular dump is actually a good kayaker. I have paddled with him at Montana del Oro and other tricky spots along the coast. He has come up the learning curve very fast this year. 

As to the offhand comment by one person you recounted that different people do different things, I would hardly hold that to be a valid statistical sample of club sentiments.  I find that improvement suggestions are better offered and received later on, after things have calmed down.

The CKF leaders are usually very good about announcing the hazards in advance and taking care of group members. Most of these incidents happen  on sandy beaches, which considerably reduces the hazards.

Others of the capsizes occurring were in surfing situations. For instance, Mike Brown and I were in very tricky coastal shoal conditions in big surf when his deck was stove in by a plunging wave. Capsizes are quite common in such environments. For example, in two surfing sessions, I capsized five times and recovered three times. That is not very often at all for kayak surfing in winter.  When I'm upside down in rough, shallow water, I tend to pull the rip cord faster, especially if it looks easy to swim in. Executing a heroic and photogenic roll has to be balanced against the risk of snapping your neck.

Recently, my paddle was snapped like a toothpick while I was still holding it (albeit upside down on a shoal in dumping surf). That's a bit unusual. I think part of the problem was the Swift paddle, which is too much of a compromise to reduce weight. I have never had such problems with my Werner paddles.

Likewise,  Steve Brown's adventurous rock gardening and surfing expeditions yield their share of spills and thrills. That's why we do them. You may be missing the point.

I think that some of our composite kayaks are built a little too light for these winter surf conditions and may not be appropriate for surfing.  That's why I usually use my plastic Necky Looksha Sport or Perception Pirouette for those conditions.  But, sometimes, we're out paddling in the composite boats and just see these interesting "opportunities" J

If you are overly upset by what you see, perhaps you will offer us the benefits of your instruction.

Happy holidays,

George Miller

 

Hi John:

How about Silly Putty?  Your kayak did pretty well in the rough conditions on the Gaviota Coast yesterday. Nice to see you there!  Seriously though,  I agree with your thoughts about semi-rigid structures.  The Polynesians already proved that with their ocean crossing "lo tech" craft-- rafts tied together with vines and stuff.

Regards,
George J. Miller

 

Gordon:

Happy holidays to you, too.

Years ago, I had a 16' wooden outboard boat, that was worn, leaky and literally falling apart by the seams.

I reinforced the ribs with 1/4" plywood gussets, with SS bolts, beefed up the transom and added 4" fiberglass tape and epoxy resin to all seams. I then covered the entire bottom with fiberglass and polyester resin. Ten years later, when I last saw it in the possession of a new owner, it was still doing great. Of course, it never had the experience of Bomber Brown piloting it under seven foot dumpers...

Regards,
George

 

A little more on plastic vs. composite boats....

I have repaired composite boats (fiberglass and kevlar composite) more than once and have seen that they are very repairable, often by people with little experience, once they learn a little.  Plastic boats are not so simple.

Joanne Turner, co-owner of Southwind and incidentally, founder of CKF, had the following input for us today (I hope I got all of this right):

-          Fiberglass is the easiest to repair by far. Kevlar is not much harder.  Recent repairs on my Perception Eclipse demonstrated that Kevlar is rather hard to "feather" (sand the edges), so it is better to do a final top layer of fiberglass.

-          Plastic is initially more durable on rocks, but is subject to catastrophic damage, in very difficult conditions, that is more difficult to repair.  Best way to handle temporary repairs is to wash, dry, clean with acetone, then apply duct tape. It tends to come off every few hours.  Sometimes a bad rip is almost impossible to fix.

-          Plastic boats can often be heat welded, with a heat gun or butane torch.  Joanne recommends using a piece from the original boat, taken from an inside area where it won't be missed.  She says that Doug and Harold from Southwind are both quite proficient in performing such repairs.

-          She disputes the assertion that plastic boats can't be repaired in remote places, suggesting that you can bring along a small butane torch to effect emergency repairs.

-          Joanne says that most plastic boats are made from Linear Polyethylene, which is fairly repairable. Some really cheap boats are made of cross link plastic, which is definitely NOT repairable.  In my consulting experience with injection molders, I learned that cross link can't even be re-melted.

-          There is a third type of plastic, used by kayak builders such as Prijon. It is more rigid and smooth, resulting in faster, stronger boats, which are also easier to repair.

Thanks, Joanne, for your always valued input.  Please let us know if I missed anything or if you have more to tell us.

I use plastic for rock gardening, composite for most touring. I currently use plastic for surfing.

Someone please pass this on to SDKC, as I am not a member.

Regards,
George Miller

~~~~~~~~~~~

 

Hi Sid:

Your comments are right on. I don't know a lot of people with more credible practical experience on the subject than you have.

What's your opinion on epoxy resins?  They aren't used much on kayaks, probably because of cost, environmental and allergenic problems. I've used them for powerboat and kayak repairs successfully. Bonding to poly is OK, with proper surface preparation.

I may experiment with repairing my snapped Swift paddle (still again-- or maybe give it a decent burial at sea) with epoxy, but first I need to find an appropriate matrix material. Any suggestions as to product and source?

Happy New Year!

George Miller

 

Okay, I'm going to risk showing my ignorance and engineering ineptitude (which has never stopped me before) by jumping into this thread.

 What about wood?  I have a wood-core kayak.  It's a Chesapeake 17.  The prime reason for this choice was economic.  It's much cheaper to build your own wood boat than to purchase a similar composite boat.

 I'd be interested in people's thoughts on the structural properties of a wood-core boat vis-a-vis plastic, fiberglass and Kevlar.

My boat uses Okoume plywood as it's basic structural element.  It's a pretty high-quality plywood, free of voids.  I can't remember if it is 6mm or 4mm thick.

The hull has a layer of 6mm fiberglass cloth over the outside, filled with epoxy resin.  (I was surprised by George's comment that epoxy resin is uncommon in composite boats - among wooden kayak builders it's pretty much the only type of resin used.)

The inner hull has epoxy-paste (epoxy mixed with wood flour, to the consistency of peanut butter) fillets in the seams, where the four plywood panels are joined, covered with 3" wide fiberglass strips and epoxy.  The only other use of fiberglass on the inner hull is on the floor of the cockpit, to protect the hull from whatever I might do to it by sitting on it, sliding my sandy feet, etc.

The deck of my boat has no fiberglass at all - just a sealer coat of epoxy resin inside and 3 coats outside.  The manufacturer of the kit - Chesapeake Light Craft (www.clcboats.com) says that it isn't necessary, and the weight savings of not glassing are worth it.  It seems like it's strong enough with just the plywood.  It's bent into an arch, which is pretty strong.  They do offer an "expedition" package, which includes fiberglass for the outer deck.

 I'm now in the process of gearing up to build another kayak - this time a strip-built Guillemot, from Guillemot Kayaks (http://www.guillemot-kayaks.com/).  My decision to build this boat is part economic - I will still be able to build it for substantially less than the purchase price of a comparable store-bought boat; part aesthetic - I love the way these boats look; part recreational - I think I enjoy the process of building as much as I like paddling the product; and part functional - the strip building process allows a much more rounded boat shape than the stitch-and-glue process used by my Chesapeake.

Weight is not a determining factor for me (see below) but I think strength is very important.  I'm wondering how strong the Guillemot will be compared to the Chesapeake, or a fiberglass boat, or kevlar, or plastic.  The 1/4" thick, 3/4" wide strips - probably most will be western red cedar, with some redwood and spruce for color variation and accent stripes - are glued together edge-to-edge with yellow glue.  That doesn't sound very strong.  But the wood strips function mostly as a form for the fiberglass - one 6mm layer inside, with (maybe) an extra layer in the cockpit; and one 6mm layer over the entire outside of the hull, with an extra layer over the whole bottom below the waterline, plus an extra layer in the center of each end to serve as extra rub protection for when the boat is pulled ashore, or slid out to sea over a rocky beach.  How do you think such a structure would compare, strength-wise, with your typical fiberglass or kevlar boat?

I don't have a problem adding extra glass, wood, or whatever to strategic areas.  For instance, I'll probably put some kind of reinforcement behind the rear bulkhead, for when I have to sit on top of the boat prior to reentering after a capsize.

 

I'm amused by people who worry about every ounce of weight, although I think my amusement is aimed more at myself than them.  I say that because I'm proud that my wood boat is pretty light, but when I paddle I typically load it up with a collapsible ice chest, a folding chair, extra paddles (Carlyles - cheap and heavy!), a book, snacks, a dry sack with a towel and dry clothes, etc.  (I actually think my boat handles better with a load.)  I usually bring along so much crap ("better to have it and not need it than to need it and not have it") that a few pounds of weight reduction in the construction process of the boat hardly seems important.

(By the way, I'm guilty of the same kind of thing when bicycling.  I sometimes am tempted by ads for expensive titanium bikes which weigh 5 or 6 pounds less than mine, but then I realize that I always ride with wrenches, a heavy chain tool, a few extra metric bolts, a spare tube, a pump, a fleece vest, a cd player and cd's, extra batteries, a sandwich, and two big water bottles.  Oh, and I have a really cool Goofy horn on my handlebars.  Squeeze Goofy's head and honk at friendly pedestrians.)

I think the weight issue in kayaking is more of a concern when carrying than when paddling.  But if you're big enough, and don't mind carrying a few extra pounds.

Any thoughts out there?  (I know there are tons of thoughts, and many excellent thinkers.  Anyone care to share a few?)

Happy holidays from little old Los Osos.

- Gordon

 

Gordon, you may find that un-glassed 4mm plywood has very little puncture resistance once   something sharp hits it.  The Okoume is wonderful stuff but the epoxy alone will not keep it from flexing and opening up little cracks that exposes the nice porous Okoume to water stains.  I built a Patuxent 17 7+ yrs ago in the S.F. area and used it in the bay and ocean.   The CLC recommendation that glass isn't needed is based on flat water use around the Annapolis area and no rescue practice as a way to keep the weight down as much as possible and NOT from experience in coastal conditions,, that's where I live right now, I’ve paddled on the west coast and you won't find ocean conditions unless you drive 2 1/2 hrs from Annapolis  and most of the time the waves are small compared to what happens off of  any beach out there, to say nothing about rocky conditions.  The places where people paddle in the Chesapeake are for the most part protected and muddy.   Of course 'sea kayaks' are not surf boats but it is reasonable to make a 'sea kayak' that will be used in coastal conditions be up to the task.

I had a person spot me while in a kayak with un-glassed 4mm deck, in one of the rescue maneuvers the bow of the other boat pierced the deck a bit with their bow.  Glassed Okoume is very tough but if   plywood is getting stressed with impacts then there really should be glass on both sides.  In a series of classes I did 2 1/2yrs ago with CLC boats that had un-glassed decks and inadequately reinforced aft hatches, 3 hatches failed catastrophically, two decks broke, and all of them elicited cracking sounds.  All of the boats now have 4oz deck glass and better hatch reinforcements.  Along these lines Betsy Bay kayaks are very light and not meant for bashing but if you're making your own boat it's fun to see what works and doesn't.   If you've got a standard Chesapeake then you might notice that in the aft compartment between the 3" tape that the bottom hull panel is un-glassed, some folks have found that the flexing ! that can occur there on kayak karts or gentle point landings on rocks can crack the wood in a way that will not occur in the cockpit area.  Like a glass hull cracking sounds don't indicate anything catastrophic but in the wood boat will allow water to intrude into the relatively dry wood and start staining things.  In that particular area it is a warning that the wood was flexed to minor damage, even with 4oz glass on the interior in that compartment the amount of resin used wouldn't be much different than what is there to seal the wood and will do a lot to prevent the cracking that opens the grain.   Likewise putting a piece of 6oz under the aft deck between the bulkhead and hatch opening will address stresses found in rescues.

If you want to go to the next level of protection then s-glass will have some of the benefits of Kevlar in abrasion and tension but   better attributes of compression than Kevlar.  It'll hold the wood together better as the wood fibers fail compared to e-glass.

Back to the original comment as to whether composite "  boats are up to it.."  it's worth looking at the difference between a large oval shaped hull cross section  like the Tesla and compare it to a smaller diameter  and less oval hull shapes to see that the total stress of a dumping wave and where it's concentrated can quite different.   Another reason for enjoying small boats, 45lbs of material in a small boat for a 150lbpaddler  is a heck of a lot tougher than 45 lbs in a boat designed to carry a 250lb fellow.   drop a shot glass or drop a champagne glass,, they're both 'glass'.

cheers, LeeG

 

Cruising PCH vs. 4 wheeling off road? Same subject no? You don't take a BMW sports car off roading do you? You don't take a touring bike on mountain bike trails and you don't spit into the wind. There's a reason you don't see 17- 18- 19 foot glass or Kevlar boats in the Best of the West kayak surf contests. They're touring boats that can make surf launches and landings. They're not designed with the intent of being a surf play boat though.  Now repeat after me, touring boats are for touring, surf boats are for play in the surf and river boats are for rivers. It's really very simple, the right boat for the right application. Use your touring boat for surf play and continue to make repairs or replace boats.

Mike

The Tsunami boats are a custom design for the extreme conditions and their adrenaline of choice are rocks, caves and large surf.  These boats can take a beating! They're expensive (excess of $3,000.00). A 15-16 foot Tsunami boat can weigh as much as 55-65 lb. They use a heavy fiberglass and kevlar lay up and are tough boats to say the least! For the rocks and caves of No. Ca. they are great boats but a little over the top for So. Ca. and our barren beaches.

We have late breaking dumping surf on most of our So. Ca. beaches. Wayne Horodowhich made a great point. If you want to play in surf, get a cheaper plastic boat and practice until your tired. Save your glass or Kevlar boat for touring as it was meant to be used. When you do get into situations with your glass or Kevlar boat you should be able to brace and ride it out safely after all the practice in your plastic boat. Wayne's other point was that the glass and kevlar boats are designed for head on impacts. Excellent statement!

I think it might be important to note that some kayakers know when to sit on the beach and watch like Duane stated in his trip report. If I remember right there were a couple of kayaks that broke that day as well. Just a thought. Desecration and judgment can be just as valuable as a good lay up of composites.

Mike   

ST,
Your right! Thanks for the correction. There's also a delicate dance accompanied by knowing when to treat our fragile boats like "Waterford Crystal" as opposed to a "LA crash and burn police chase" on a late breaking dumping surf beach. Your right about a T-rescue in rough waters as well sir.

Mike  

 

Greetings all and hope 2003 is as enjoyable as 2002 for the club outings. I love reading the trip reports and the dialog on the e-mails.  Here are some additional thoughts and considerations.

Back to the basic question - Are composite boats really up to the rigors of open ocean paddling, including launching and landing in moderately large surf?  This is a two part question.  Open ocean Vs launching and landing.  In my opinion, launching and landing is different than playing in the surf and being in the location of where the wave is breaking.

I have had the good fortune and pleasure to speak with many of the main designers of the most popular kayaks out their (composite and plastic).  To the best of my memory I have never heard any of them say they have designed and built their kayaks with a main design feature being the thought of the the weight of a big dumping wave on their decks.  The closest I have heard was the reason for the use of Kevlar.  The weight to strength ratio is stronger for straight-on impacts.  This helps with direct impacts.  However the shear strength is reduced.  This means that if you do a nose dive with your kayak and hit bottom the damage could be greater.  The strength in Kevlar is direct impact which is perpendicular to the material.  I know the Tsunami Rangers Custom Rock Garden kayaks are made for impact in mind but they will be the first to admit the have had to repair their kayaks due to the forces placed upon them.

I believe the majority of ocean kayaks are suited for open ocean paddling.  I don't think any kayak is designed for taking the forces of the ocean when you are in the location of a breaking wave.  Some kayaks will do better than others but those forces can be so great how could you build for them and still be able to lift the kayak.

Think of it from the designers viewpoint.  They are designing boats for paddling.  They are concerned about tracking, edging, stability, maneuverability, cost and weight.  The kayak's main function is that of transportation.  The analogy of the BMW sports car being used for 4-wheeling is the best answer to your question of a kayak being suited for taking the force of dumping waves.  I have not seen a dumping wave simulator in any of the manufacturer plants I have visited.

When I got my custom lay-up for my kayak I wanted Kevlar for the weight reduction and the boat designer told me it wouldn't be strong enough for my size and weight and what I have been known to do in my kayak. (height 6'7" , weight "none of your business J ).  He suggested a hybrid of Glass & Kevlar.  It was also reinforced in key areas.  Extra heavy lay-ups are common for those who like to push their limits but damage still occurs.  The bottom line is kayaks get damaged when put under a breaking wave, don't be there if you want to keep your kayak intact.

However, as an instructor I also know that sooner or later one will end up in the wrong place at the right time and have a wave break on them.  Therefore, shouldn't one practice in those conditions to learn what to do?  I believe so (to an extent).  That is why we use plastic kayaks for that  sort of training.  However, we accept that the plastic kayak can and does get damaged in those conditions.  It is part of the process.  Our goal in the instruction is to teach the paddler how NOT to be where the waves breaks.  I suggest getting a carnage kayak (like rock skis) if you want to do that sort of practice and playing.

The trend in manufacturing is significantly based upon consumer demand.  The consumer has been led to believe lighter is better. I too like lifting less than lifting more.  However, how strong are the lightweight materials?  Are they strong enough for the forces  YOU paddle in?  If not, get YOURSELF stronger equipment or alter where YOU paddle.  You can have the best of all worlds by having a lot of equipment.  Those who know me know I use a two paddle philosophy.  A stronger paddle for launchings, surf work, landings, rocks & caves, and rough  water.  My light weight when it is long distance calm days.  Both are with me when I go out so I can change to the conditions.  I do the same when I play in the surf.  My carnage kayak for the surf zone.  My touring kayak when I want to go paddling.

Keep up the carnage.  I love reading those stories.

Neptune Rules!!!

Wayne Horodowich

 

Hi All,

I just got off the phone with George Miller (prompted by a comment in his e-mail) and I discovered I used the wrong term when I said Kevlar had less shear strength.  The term I should have used was compression strength.

Thanks for the correction George.

Wayne

 

High performance surf kayaks are of composite construction, and regularly take hits in large surf (8-12ft) without incident. They are usually layed up a bit heavier, but surf kayaks in the 8ft range with bomber layups are being built that weigh 16lbs.

A boat like that will run about $2000. I think a touring boat with a layup used on these surf kayaks might be prohibitively expensive for many paddlers.

A cheaper remedy may be to install mini cell pillars, front and rear, to stiffen the deck. Just about all surf and whitewater kayaks have pillars for this reason.

~John

 

I've been thinking in the same vein.  For the last year I've been looking for a boat for my girlfriend that would be comparable in weight and handling to my glass Solstice. So that we would be evenly matched. But now I'm seeing that there is a lot you have to watch out for in a glass boat that wouldn’t be a problem for a plastic boat. 

Steve Keene

 

Steve,

Since you are asking for opinions, and mine are as valid as anyone else's, here's my 2 cents.

I think that the current marketing for most manufacturers centers around weight. Somehow everyone seems to be getting the idea that lighter is better. In my not so humble opinion, that is not always the case. Most of the North American boats seem to me to be built for "calmer waters." However if you check out some of the "British Heavies", I think you will see some real differences in construction. Take a look at the Nigel Dennis, Nigel Foster, and Derek Hutchinson designs. These boats are all somewhat heavier than comparable N. American designs. There must be a reason for it.

After seeing a number of lightweight paddles break, I use a heavy graphite and FG paddle that weighs 41 oz. - but it handles pushing off from the beach and rocks a lot better than my just as expensive lightweight paddles.

So--IMHO, lighter is not always better.

Steve Holtzman

 

George, Wayne et al.

    “The term I should have used was compression strength.

     Thanks for the correction George.”

Yes, Kevlar and fiberglass have no compression strength. The resin provides that. Vinylester resin is more flexible than polyester.

George, thanks for your discussion on the properties of various materials used in hull construction. Although I took the standard courses in materials science, I have always worked in metal finishing (electroplating, immersion coatings, anodizing etc.) and water quality (pollution) control. I am not a polymer chemist.

I have seen a number of Kevlar/glass boats damaged under ordinary "working conditions". Typical Kevlar/glass lay-ups strive for minimum weight but sacrifice compressive strength and an ability to dampen forces. The Kevlar fabric does seem to remain intact and prevent leaks until repair can be made.

Perhaps Kevlar in addition to the usual lay-up for a glass only boat is best.

But of course there are many sea worthy plastic boats and one should never be too proud to paddle one if that is what is available.

ST

 

Although I am a chemical engineer, rather than discuss materials, I'll simply pass-on a few observations and a couple of personal experiences.

Force 10 and the Tsunami Rangers use composite boats (to my knowlege). Of course, this is for rock gardens not touring.

I once saw a Tesla in Ed Gillet's shop in pitiable condition. He assured me that it would soon look and be "as good as new", a prediction later borne true.

Polyethylene has a shorter shelf life than glass. Volatile components eventually say adios and it cracks. Despite theoretical assertions that it can be welded it is problematic, besides the material has no integrity at this point anyway, unless it is simply a shark bite on a relatively new boat. If you use acetone first you may be able to get duct tape to stick. .. kind of like using a sail to staunch a leak on a wooden ship.

After some 3,000 miles and a hundred different landings, lateral cracks appeared in the mid section of my Arluk III. I repaired it (reinforced it) mid tour. I have seen four mid tour repairs with glass. In one incident a plastic Narpa made the landing without damage (but with more skill).

Composite boats can exceed the length/width ratio of a plastic boat.

Composite boats are faster, though it depends on who is paddling. Speed (distance made good) is important while making a crossing.

Much of the discussion on launching and landing relates to empty boats. Loaded boats behave differently. If you get swamped in the surf the loaded boat stays with the water while waves wash over (there's an alliteration!). It will be a bitch to get it to shore. Touring boats are not surf boats ideally. The most crucial part about launching is getting the loaded boat afloat. Once you have broached you got to get out, right the boat seaward and try again. Getting someone to hold the bow and give you a shove offers the best prospect for a successful launch.  Landing you try to stay on top of the wave and ride in on its crest ideally, but often you must (especially in a shoal) broach intentionally and do a high brace seaward. This can be bumpy but it better than windowshading (or pitch-poling).

The only boat I ever destroyed was glass. It was a foolish launch in rocks and weather. The tail section levered in the rocks and I paddled off with a shredded stern. A plastic boat might have survived (mine sank).

I have paddled the 1100 mile long CA coast and made 36 landings. I always intend to land in protected places, especially harbors and the like. This is not always possible. I bought a plastic boat for the northern coast anticipating rocky landings but was unable to foresake the beauty and speed of glass. The Narpa was left at home.

But after all, it is the paddler not the boat that finds nirvana. Kinda like those SUVs in gridlock traffic.

ST

 

Mike,

“Desecration and judgment can be just as valuable as a good lay up of  composites.”

I'm sure you meant discretion and good judgment but thanks for the malapropism.

ST

PS: That strength that absorbs head-on impact can also bash a hole in the side of a glass kayak for those that regrettably attempt a T-rescue in rough water.

ST

 

Steve,

Sorry to hear about the damaged boats...think I'll stick with my invincible SOT plastic boats for now.

I hope that you and your family has a great Christmas.  We have a lot to be thankful for (especially you with all the wild waves you have been on this year!)

I will be on vacation but staying home for the next week and a half and I'd like to surf with you all at Bluff Cove one morning (if you are not in Baja)

If I don't see you before then, have a great New Year.

Richard

 

Steve:

Not all composite boats are created equal.  I don't know what makes one kayak stronger than another.  Layup, of course. Location of bulkhead(s)?  Shape of deck?  Length of boat?  Design?  Some composite boats feel solid, others feel "flexy".  Maybe Nigel Foster could shed some light on this.

I paddle a Dagger Meridian, and it has handled everything I have given it (although it would prefer that I not hit rocks).  I know many people who paddle then in NoCal, and only one has managed to beat one up pretty bad.  This was due to impact with rocks in a surf zone, and was not at all like the photos of Mike Brown's Tesla.  I would be surprised if a four footer did that kind of damage to my boat.  I don't want to sound like I am bragging. 

Maybe I will have to take it out and see what happens.

Jonathan

 

Steve:

Just some quick thoughts:

  1. There are expeditions done in plastic.  Read anything by Jon Turk?</