You guys are in trouble!!
Trying to educate with facts…how dare you…You aint gonna get on the mother ship now!
Nice stuff onnopaddle!
disagree
have seen several kayaks with deep sctatches in their gel coats, which on a non-gel coated kayak would likely reach the fibers and require a repair-would not want that to happen on the first day of a five day trip.
Also, my car has a “gel coat” on the paint is called a clear coat and has saved the underlying paint from getting damaged many a time.
Maintenance is for guys that enjoy it
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I have a fiberglass seakayak that I use. What I mean is I launch and land on cobblestone beaches and run over beaver dams and play in the surf and class 2 rivers. I use it a lot. Just short of willful abuse. Scratches happen. Cracks happen. It didn't take long to put a few scratches on it. It didn't take long before I needed to repair damaged areas. Thing is fiberglass is awful easy to repair. Now, I could be fixing or repairing my boats every weekend if I was hung up on their appearance but I tend to be lazy and save repair work for more of an annual activity. Like an hour or two a year. In the mean time the boats look like someone has been using them. I use to think I could never enjoy a composite boat because I would surely destroy it in short time but the reality is that although my 5 y.o. seakayak looks like it just got shot from a volcano, it still paddles great and has nearly as much life left in it as it did when it was new.
Truth is I cant stand to see a boat that looks perfect. It makes me wonder if it ever gets used. I see a composite boat that looks perfect and I think how sad is that.
Plastic is still too heavy.
VERY nice site pat …
excellent discussion of both boat and paddle production by a master craftsman.
agree and disagree
clear coat is not gel coat, it’s a clear coat.
You’re right that gel coat provides a sacrificial layer,but I’d just as soon trade a sacrificial layer of s-glass for gel coat as it will be a lot tougher for the weight. So instead of 1mm thick sacrificial layer of gel coat have .75mm thick sacrificial layer of s-glass. While you will scrape into the glass it will be tougher than the gel coat and provide more total impact resistance.
well
if you ever put a clear coat on a car you would know why I said it is like a “gel coat”!, it goes on as a very thick “gel” and then dries down. Point is it serves the same purpose. I saw an Epic composite 18 (versus the non-gel coated carbon/kevlar) at a local shop that had a deep scratch in the very thin gel coat, looked to me like it had reached the glass and was just “painted” with white epoxy paint to hide the exposed glass. On sandy beaches shells can cause that kind of damage.
And I disagree with someone else who said that gel coat is not a structural component of the kayak, of course it is. Take it to the extreme and make the gel coat 1" thick, whould that make the kayak stronger and more rigid?, I think so.
Note that a cut into the outer fiber
layer does NOT mandate a repair, even on a thin slalom racing boat. If it did, we would be spending half our time on nickel-and-dime repairs. Exposing the outer layer of S-glass, E-glass, or even Kevlar, has no long term consequence whatsoever. It is the non-harmfulness of cuts into outer layers of cloth that makes light, flexible, stiff boats possible.
Gelcoat does only three things that I know of. It is colorful. It screens out some UV. It is an ablation layer for abuse.
No it isnt
I have seen a near new plastic boat get a hole punched in it the size of a fist. When the plastic becomes brittle it cracks very easily.
Sure it does
fiber glass and kevlar will asorb water. Take a kayak with exposed fibers (from cuts or cracks)into salt water and then let it dry, you will see salt crystals around the exposed fibers and cracks. How much water do you want to take on?
Also, the more you damage the fiberglass the more you weaken it. It just takes a hard impact to prove that point.
Beg to differ…
“if you ever put a clear coat on a car you would know why I said it is like a “gel coat”!, it goes on as a very thick “gel” and then dries down. Point is it serves the same purpose.”
…and I do put clearcoats on cars nearly every day of the week.
Whereas gelcoat may be an optional aspect of a kayak finish the clearcoat on a modern vehicle is a required component.
The underlying basecoat has little chemical integrity without the protective clearcoat. Additionally, the basecoat cannot exhibit its colouration without the clearcoat, e.g. pearls, micas, elliptical metallics, etc.
I’m not sure what you mean by ‘drying down’ but automotive clearcoats and marine gelcoats have substantially different voscosities as well as dramatically different final mil build.
I do not have advanced expertise in gelcoat application so I’ll not address the issue of its structural integrity or lack thereof. It should be noted, however, the analogy drifts farther awry as automotive clearcoat does not provide structure integrity for the vehicle concerned as is claimed for gelcoat. Automotive clearcoats must be configured to flex dramatically when applied to synthetic components far beyond the flexible range of gelcoat.
If gelcoat can be truly considered an optional and sacrificial layer in terms of boat construction than it truly cannot be compared to an automotive clearcoat which is neither sacrificial or optional.
Holmes
Beawolf
No offense at all meant here, BUT I think you know very little about composites. I know my mind has been opened in the last four years or so, and much of what I believed 10 years ago, I no longer do. On the water destructive testing involving many boats has really been shocking. Keep messing with it all!
No they don’t. Water is absorbed only
into micro cracks where the resin and cloth have been mechanically parted. The capillary space within glass strands or Kevlar strands is occupied by resin. And Kevlar absorption of water is quite local. It does not travel long distances within the strand.
No builder of composite whitewater canoes has EVER recommended repairs of surface scratches. That’s because they know it doesn’t matter. It seems to be a neurosis of some sea kayakers.
If you were correct, then my unrepaired composite boats should have gained weight over their 10 to 30 year lives. But they haven’t gained ANY weight. Where are you getting your suppositions? Then we’ll decide whether to call it information.
Another composite with no gelcoat:
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All the composites built by Adirondack Guide-boat. The vibrant colors of these boats always made me assume they had gelcoat, but last year the salesman told me they don't use it because it adds too much weight. If I understood him correctly, he said they mix the color pigment with the resin. Some of the scratches to my boats built by them seem to support that idea (the cloth is the same color as the exterior). They do, however, apply a mixture of graphite and epoxy to the most wear-prone surface of the bottom of the hull, which seems to help a bit.
well
I have repaired my fiberglass sufboard and the repairs have held up to some extreme pounding so I guess that counts as experience-to me!
Never
said the water “travels” down the fibers, please re-read my post. As for fiberglass and kevlar asorbing water, versus just the voids in the cracks, that may be hard to prove one way or the other. But when finberglass is “cracked” the resin that surounds the fibers is broken up and the exposed surface of the fiberglass can asorb water.
And as for your kayak gaining weight over the years, as I mentioned it “dries” out after use! Please do not exagerate my posted statements. Now if you always kept it in the water then it would never dry out and would gain water weight due to the retained water, how much would depend on the damage to the surfacce and underlying fibers.
How much experience do you have?
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A clear coat on a car is not required and many do not have a clear coat!!! A clear coat is either an option, or is only appled over a metalic flake paint!!!
The clear coat protects the paint and underlying metal on a car, just as a gel coat protects the underlying fiberglass on a kayak.
Pretty simple anology
Really now…
—“A clear coat on a car is not required and many do not have a clear coat!!! A clear coat is either an option, or is only appled over a metalic flake paint!!!”—
Not even close, pal. Less than 10% of currently manufactured vehicles use a single stage finish, that is, no separate clearcoat. Additionally, ALL colours originally formaulated as basecoat/clearcoat REQUIRE a clearcoat. The base is a dull satin finish with little integrity. Try ordering a blue pearl Dodge without the ‘optional’ clearcoat!
The EPA has removed many of the hazardous components, e.g., lead, etc., from automotive pigments thus dimishing their resistance to chemical and ultraviolet light. This is the reason clearcoats are nearly a universal necessity now. It has very little to do with metallics.
Ever see any of the infamous ‘peelers’ that have plagued all the manufacturers? White Buicks, silver Fords, and on and on. This was caused ny cost saving bean counters recuing the mil build of clearcoats to help their bottom line. Non-metallic colours were affected just as the metallics and pearls. Simply not enough of that ‘optional’ clearcoat!
—“The clear coat protects the paint and underlying metal on a car, just as a gel coat protects the underlying fiberglass on a kayak.”—
Your argument was that gelcoat offers structural integrity to a kayak. An automotive clearcoat does not. By your broad analagous standards you would be able to compare wearing a shirt to the use of gelocoat.
BTW, I am currently celebrating my 20th year as a certified ICAR refinisher/instructor.
Have a day.
Holmes
Why do people on this post
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go to such extremes to try to prove someone wrong? If you read my post I said a gel coat does several things, including being a structral component of a kayak. So the analogy is not perfect, is any anology? That is not what an analogy is supposed to be, i.e., a perfect comparison.
As for clear coats, I just did some refinishing on my car 4 months ago. I was given the choice of getting either an all-in-one metalic paint that did not need a clear coat, and a metalic paint that needed a clear coat. This was from a local automotive paint store that supplies all the auto paint/body shops in the area.
So are you telling me this is not true? As for "new" cars I only have experience with factory finishes from ~9 years ago when I bought my car, from what you have said things have changed. BUT I also had a professional body shop repaint part of my car LAST YEAR, they used an all-in-one paint and what I see now is that it is easily chiped by road dirt BECAUSE it does not have a clear coat to protect it!!!!!!!
Am I making my point clearly?, or are you going to focus on one word to try to contradict it? PLEASE, some maturity would be helpful around here.
I say that you do not understand
composite construction. I also say that there is no point whatsoever repairing scratches that go into the cloth. Whether the boat sits in the water or dries out in the carport, it will not gain weight.
Seriously, what do you know about bruised composites?