Necky carbon Chatham 17

Curious if anyone with carbon Chatham 17 with serial numbers ending in 000 ever had problems with wet core in the cockpit.

You mean it’s foam cored, and you can
tell that water has infiltrated to core in the cockpit area? I’m not familiar with core materials, but I thought the foams were close celled.



I’d call Necky and describe the symptom. A proper layup should leave the carbon effective as a water barrier. But me, myself, and I might add a less brittle, tougher cloth with good resin affinity (CAP for vinylester) for insurance against local damage of the brittle carbon in the cockpit area, which is stressed inside and out by actions of the paddler.

Where was it built?
If it was built at Old Town there were numerous problems.

If it was built in Thailand by Cobra Int. It will be well made.

Having moved on from the industry my info is a

Few years old but may apply. The core used is

Soric which has a hexagonal pattern. These are channels

that fill with resin during infusion, or hand layup.

If the infusion process is rushed or hand layup fails

to fill these channels in the Soric water can migrate

Inter laminar-ally and even though bulkheads are

perfectly sealed you’ll get water moving through

the matrix. I saw this on occasion. Soric is best

with infusion, but can work with hand layup if done well.

I’d bet money this is your issue. When I was in RD carbon Cobra

Boats were infused to avoid tiny micro bubbles and

for better aesthetic with Vinylester. Glass boats hand lated with epoxy and post cured. They are much tougher and weight

Very close. Carbon is bling in this case. Good luck.

Cobra
About four years ago, three carbon boats. One boat had wet core, push thumb into floor in front of seat and bubbles of water would rise up within 1" away. Cut section out and core was wet.



Paddler got second boat under warranty but he decided to glass cockpit to forestall same problem.



Last of three and I’m seeing similar yellowing of core and a bubble of very light interior glass that can be scratched off with finger nail.



These were from a time when serial numbers ended in 000 for a couple years providing inaccurate designation for year of manufacture.



Just curious if others had similar problems with the 000 “yrs”

Hmmmm. Resin starved I’m thinking
Lee, again I was not involved at that time but

I recall those being infused. My sense is that the

infusion process was cut short and or there was not

adequate layer saturated above the Soric core.



Soric is a polyester as I recall and it’s the channels

that fill with resin not the cells which are core. It’s

similar to core matt but works with infusion as channels

create good flow. I like Soric a lot for stiffness and

toughness but like any material the process has

to be right. I did see some resin thin boats early on in

the Cobra roll out but these issues were fixed and the boats

We’re crazy tough and durable.



All that could be done at this point is a resin coat with

A thin layer of glass. I think that would work.



BYW this water in the matrix migration has occurred in

several brands and some builders do a quick fix

by waxing the interior! Makes repairs tougher!



I’d say call customer service but I don’t know anyone

there anymore so not sure if you’d get informed help.

Worth a try and see if they will give you a Cobra contact.

Used to be a guy named Vicrom there who was solid. Think

he left but came back

Delamination?
I’ve seen something similar on a honeycomb core surf ski that was likely damaged by it being strapped to a kayak rack too tight. The inner layer of fiberglass was no longer adhering to the core and water could get between it and the core. But the core channels were filled with resin, so there was no water absorption beyond what was just sitting between the layers.



The delamination was barely noticeable too, only from the inside and the hull was still stiff. No sign of this from the outside and even from inside it was very hard to notice: the boat was still new and the water had not had time to discolor the laminate, and the inner layer was actually almost flush - there were no visible bubbles, but if you touched it you could feel and see it was not glued to the core.

Very different cores
Surf ski most likely nomex core whih is a very light honeycomb.

Makes for very light and stiff laminate but poor impact resistance.

Soric is not a honeycomb, rather a Matt with channels through it in a

honeycomb pattern. These channels fill with resin and the cells of the

core remain dry. It’s not a light core but it’s great for impact and stiffness.

Was the Soric.
Yup, was a Soric with honeycomb patterns. The heavier of the two available options at the time. It was a 37lb hull, way too heavy for a ski.