Misconseptions about gelcoat

Another composite with no gelcoat:

– Last Updated: Apr-09-06 12:53 PM EST –

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?

– Last Updated: Apr-09-06 1:19 PM EST –

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

– Last Updated: Apr-09-06 3:12 PM EST –

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?

OK
The paint choice you were given involved two different kinds of paint, one was a single stage while the other was a two-stage. They use different toners entirely and quite often different catalysts.



Completely different products, not simply an optional clearcoat.



In terms of your car repair, the chipping is unfortunate but has little or nothing to do with it being a single stage or a two stage. There are a number of issues that can result in easily chipped paint, most of which involve application. Too much catalyst, not enough mil build, reducers that are too hot, improper surface prep, etc., all contribute to a lack of adhesion and/or reduced bruising resistance.



The shop that did the repairs should stand behind their work and refinish the car for you at their expense.



The tone of my previous response to you was based up the heading of your post to me, “How much experience do you have?”. I had already advised you of my experience but you opted for a confrontational tone and I responded as such.



Since we are now far from the content of the thread I would suggest we let this go and agree to disagree.



Holmes

How did a near new
plastic boat become brittle?



Was it excessive UV exposure or extreme cold temperatures?



Holmes

What I’m trying to say
Is that you may not know what you don’t know. I too did a lot of repairs. In the past few years I have been exposed to several composite engineers in aerospace and in the nautical world. At first they all said things that I didn’t like, cuz they went against thoughts I’d held for many years. Thoughts mostly based on marketing stuff, and common thinking. Subsequently my ideals have been blown away. I’ve test paddled 30lb. boats that held up way better than my 60lb. archaic lay-ups. I still have tons to learn, but wow, I don’t say the same things I did five years ago! I can pound on my 30 lb. boat with a hammer! I for one am not gonna dismiss the smart composite engineers, as they’ve more that prooven their points to me! I think onnopaddle has excellent info, and I think there are a lot of smart people here trying to share info…some of which goes against industry dogma…But hey, the “kayak” industry just may be a little behind aerospace and yachting eh??

well the whole
reason we got onto this topic was because of my analogy!



And I aplogize for the experience comment, yes you clearly have a lot of experience in paint.



But what I can point out about the “single stage” paint job is that the paint layer is very thin, so a rock can chip is easily. Where there is the original clear coat, the clear coat gets chiped but the paint underneath is fine. That is the point I was trying to make with the analogy of the clear coat to the gel coat.

structural component
YOu could make a kayak out of cloth and a matrix of resin and it would do what it’s supposed to do with or without gelcoat. YOu can’t make a kayak with gel coat and cloth or gel coat and resin. In other words the structure of the kayak doesn’t require gelcoat in order to provide strength or form.

what Scott said
The first gelcoat gouge my Mariner got I fixed,poorly. After that I paddled it. It’s 12yrs old and looks it. Doesn’t leak, doesn’t sink, doesn’t creak, doesn’t moan. Bottom has numerous gouges into the glass. Maybe someone will repair it someday. In the mean time,it works.

G2d is 100% correct on every reply here.

Homes … closer to gelcoat would
be all those dark blue Nissans from 10- 15 ? years ago … LOL

I have played with using gelcoat
AS the resin with glass just to see what happens when many differnt colors were used … interesting effect.

LOL!! So true N-M
.

tinted resin
is that how your boats are made? Where does the white come into the picture.

White pigment in Epoxy…

– Last Updated: Apr-10-06 3:40 PM EST –

Glass layed right into molds .... ZERO pin holes due to skillful wetout.

Forgot .... gelcoat as resin was to make a mobile .... nothing to do with boats really.

Maybe not exactly 100%
Kevlar fibers do absorb moisture into the fibers themselves. Glass doesn’t.