Gelcoat weight, AGAIN!



This is a very UNscientific test.

I found three identical small bottles of gelcoat pigment, one brown, one white and one yellow. So just for Ha Ha’s I weighed them on a real good digital postal scale, bottles and all.

The white and brown weighed the same and the yellow weighed 7.5 percent more.

There are many, many variables before it translates to kayak weight but just thought it interesting that I can pick out the yellow bottle blindfolded...

weight of pigment …
in my experience, red, orange, yellow weigh considerably more than blue, white, green.

Gelcoat is an unnecessary substitute
for a layer of S-glass. Hard, stiff, resistant to cracking, wears smooth.



Help stamp out gelcoat.



Gelcoat is like heavy pancake makeup. Necessary for ugly old broads, but a detriment to those with true beauty.

LOL G2D … daswatimtalkinbout grayhawk…

Yep…


I will always defer to you on these matters, Pat.

I just found it amazing that I could notice a difference in an amount as small as one fluid ounce…

When I was purchasing my Nigel Foster
Shadow by Seaward, the factory rep told me that most manufacturers won’t say this, but yellow is the heaviest color followed by orange.



The artists’ name for yellow is chrome because yellow pigment usually contains chromium which is very heavy. Orange is just a mixture of yellow and red.



He said that most of the other colors pretty much weigh the same.

It all depends upon the density of
The pigment & how much is required in the gelcoat (or paint for that matter) to acheive the necessary opacity to give a uniform colour.



Factors affecting the level of pigmentation include the particle size & particle shape of the pigment & required gloss of the finished coating.


all I know
is that even with sky blue deck my walden Legend is HEAVY.



But put her in the water and she dances…go figure.



The coaming at the rear is very low to the deck making it effin hard to grasp when picking it up…I guess that is my real gripe…its not really that heavy…:slight_smile: It’s even hard to get the spray skirt in there let alone my fingers.



ok done bitching.



Paul

S-glass
Can you be more specific.

google it
s-glass has a different chemical composition than regular e-glass. It costs about twice as much as e-glass or 2/3 the price of kevlar. It’s got better abrasion characteristics than e-glass and is more easily sanded/repaired than kevlar.

Kayak manufacturers could make a tougher boat using s-glass on the outside and kevlar on the inside than the current all kevlar constructions. But it doesn’t look or weigh different than e-glass or the other pricey materials like kevlar/carbon so it’s a hard sell.

If you replaced the gel coat with a similar weight of s-glass and put paint on that you’d have a structurally tougher boat. Putting on ablative strips at the high wear ends would make more sense than putting gel coat all over.



I made a bunch of test panels with 4mm Okoume plywood and 4oz, 6oz e and s-glass as well as 5oz kevlar. The s-glass was easier to weight out than kevlar in hand layups and noticeably stronger than the e-glass. A panel of e-glass and plywood would bend then shatter with broken threads and shards of plywood sticking out. A panel of s-glass would bend with much fewer breaks in the fibers and most of the shards of plywood confined within the laminate.

S-glass
Just brought myself up to date. In the end it is a trade off, performance against cost.

Who actually makes “all Kevlar”?
My “Kevlar” QCC is as you say - on the inside - glass oustide. Not sure about Kim’s Sparrow Hawk…