Nortech Delamination
#41
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Joined: Jan 2021
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From: Gothenburg, Sweden
#42
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From: Chicago

You mean you need a big budget to keep the Skater running meanwhile us poor 'budget' folks have no issues but it`s the cheaply made boat because you saw "waves" in the sponsons. Liberal Logic.
You`ve never mentined what boat you have....
#43
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From: New Smyrna Beach FL/ LOTO MM 21
I don't have a dog in the fight, or any first-hand experience with NorTechs at all but, just a fun fact....
It is my understanding, from a model boating buddy (a tooling engineer for a large fiberglass molding company in Michigan) that carbon does not "wet out" with literally any resin. It does not bond with the resin, but is "encapsulated" (his term), and is always layered with glass or Aramid, or is vacuum bagged. I myself have seen it "float" when not blanketed with some other fabric. He also told me that the vast majority of failures such as cracking or delamination are the result of too much resin, regardless of type of resin or fabric material. The resin cracks, and the crack then propagates through the fabric. With proper layup, glass and Aramid (especially) are actually quite flexible and resilient to fatigue.
That said, I would have to think that NorTech has their lamination process pretty well sorted out.
Carry on....
Thanks. Brad.
It is my understanding, from a model boating buddy (a tooling engineer for a large fiberglass molding company in Michigan) that carbon does not "wet out" with literally any resin. It does not bond with the resin, but is "encapsulated" (his term), and is always layered with glass or Aramid, or is vacuum bagged. I myself have seen it "float" when not blanketed with some other fabric. He also told me that the vast majority of failures such as cracking or delamination are the result of too much resin, regardless of type of resin or fabric material. The resin cracks, and the crack then propagates through the fabric. With proper layup, glass and Aramid (especially) are actually quite flexible and resilient to fatigue.
That said, I would have to think that NorTech has their lamination process pretty well sorted out.
Carry on....
Thanks. Brad.
This is why "good builders" use an impregnator. You can set exact amount of resin you want to have in the cloth/material being used in various stages of the layup. As I stated above, it pays to visit multiple builders and see what materials and techniques they use. I have enjoyed watching my new project transform from rolls of carbon and totes of epoxy to the boat of my dreams. I try to check on it every 10 or 12 days.
Joe
#44
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Joined: Jan 2010
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I don't have a dog in the fight, or any first-hand experience with NorTechs at all but, just a fun fact....
It is my understanding, from a model boating buddy (a tooling engineer for a large fiberglass molding company in Michigan) that carbon does not "wet out" with literally any resin. It does not bond with the resin, but is "encapsulated" (his term), and is always layered with glass or Aramid, or is vacuum bagged. I myself have seen it "float" when not blanketed with some other fabric. He also told me that the vast majority of failures such as cracking or delamination are the result of too much resin, regardless of type of resin or fabric material. The resin cracks, and the crack then propagates through the fabric. With proper layup, glass and Aramid (especially) are actually quite flexible and resilient to fatigue.
That said, I would have to think that NorTech has their lamination process pretty well sorted out.
Carry on....
Thanks. Brad.
It is my understanding, from a model boating buddy (a tooling engineer for a large fiberglass molding company in Michigan) that carbon does not "wet out" with literally any resin. It does not bond with the resin, but is "encapsulated" (his term), and is always layered with glass or Aramid, or is vacuum bagged. I myself have seen it "float" when not blanketed with some other fabric. He also told me that the vast majority of failures such as cracking or delamination are the result of too much resin, regardless of type of resin or fabric material. The resin cracks, and the crack then propagates through the fabric. With proper layup, glass and Aramid (especially) are actually quite flexible and resilient to fatigue.
That said, I would have to think that NorTech has their lamination process pretty well sorted out.
Carry on....
Thanks. Brad.
For sure excess resin is a problem as all of the strength is in the fibers. That’s one of the main advantages of bagging/infusion. It sucks out the excess resin whilst using the mass of the atmosphere to help ensure full wet-out. The resulting fiber/resin ratio is much higher so you get a similar strength without having to haul around the mass of all that excess resin. I say similar as excess resin between the inner and outer fibers adds to the section modulus -so the thicker laminate (with a bit of extra resin) will be stiffer. However, if seeking stiffness without a weight penalty, coring is a much better way to go. I am referring to high performance laminates here. If not that weight sensitive then a solid vinylester laminate is excellent. The Norwegians have been doing this for years below the water line with generally good results. Regarding aramid – if you thought carbon was hard to wet-out have a go at aramid. You also need to be careful in your laminate design as aramid has very little compressive strength. Peter Hledin is a master of knowing how to work aramid into a laminate schedule – just wish he would swap out that damn balsa for Corecell….
ND1
#45
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Joined: Sep 2013
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From: Syracuse Ny
well. It’s not 1/2” 😂 and gee, idk. Maybe cause a cat needs to fly on the pocket or air and can’t be 14,000 lbs just to name a few reasons lol
#46
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Joined: Sep 2013
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From: Syracuse Ny
This is why "good builders" use an impregnator. You can set exact amount of resin you want to have in the cloth/material being used in various stages of the layup. As I stated above, it pays to visit multiple builders and see what materials and techniques they use. I have enjoyed watching my new project transform from rolls of carbon and totes of epoxy to the boat of my dreams. I try to check on it every 10 or 12 days.
Joe
Joe
#48
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Joined: Jan 2021
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From: Gothenburg, Sweden
He would switch to foam if he could get the resin to stick as well to it as it does to Baltek. It's not like salesmen for foam cores don't have his phone number...
#49
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From: Gothenburg, Sweden
I meant that if you prioritize a big cockpit, an attractive price and a flushable toilet, you will be happier in a Nor-Tech.
If you prioritize speed, lines and lay-up, you will be happier in a Skater.
I would not call it cheaply made. But it is made to a lower target price. Among other things, that means that you use a less expensive resin. You have less shrinkage and more time and control with epoxy than with vinyl ester. Hence the wavy sponsons. Same thing with polyester boats.
Nor-Tech's pitch was value for money. You will find posts from their sales guy doing that pitch here on OSO from back in the days when they build cats.
Nothing to be ashamed of, or try to explain away with balsaphobia.
28 Skater. Not very expensive to run. Tanks have been replaced by stainless steel tanks. A proper tank job is on the to do list. The layup is a work of art. Not encountered any wet balsa.
If you prioritize speed, lines and lay-up, you will be happier in a Skater.
Nor-Tech's pitch was value for money. You will find posts from their sales guy doing that pitch here on OSO from back in the days when they build cats.
Nothing to be ashamed of, or try to explain away with balsaphobia.

28 Skater. Not very expensive to run. Tanks have been replaced by stainless steel tanks. A proper tank job is on the to do list. The layup is a work of art. Not encountered any wet balsa.
#50
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Joined: Jun 2021
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From: SW Ohio
Divinycell is an excellent option. The reason resin doesn't "stick" to a foam core...? In most cases, it does. It's the foam just below the resin bond that fails. I'd be willing bet that, if you were to examine a lamination failure where it appears the bond failed, you'd find a healthy layer of the foam still firmly attached to the laminate layer, where the resin has wicked into it. Many times, impact will cause crush failure of the foam in this intermediate layer, causing a delamination. We've seen this a lot in the model boating world, when less resilient foams are used. I'd have to think these forces would be considerably worse in our bigger boats. Divinycell is about the only one I can recall that doesn't do this. I have to think it's the cost that prevents any boat builder from using it for any foam core application.
Thanks. Brad.


