cored hulls

[med2alfa]

Greetings to all you Albin fans. I'm a new member and have been reading and researching Albin issues in anticipation of my purchase.
I have read a few posts about this subject and wish to share with you what I learned from our Pacific Northwest dealer after she posed my questions about the makeup and durability of their hulls directly to Albin Marine. It goes as follows:



"I asked Albin to email me the description of their coring material, etc. and here is the response I received from them today:

Elaina,

We are currently using Airex C-70 foam in hull bottoms..... Topsides of hull from Chine up are solid laminates....Where Penetrations go through the hull, Foam core is removed and replaced with solid glass...Core thickness varies from model to model....

Decks are cored with End Grain Balsa core on most horizontal and vertical surfaces.... Thickness varies from model to model...

Airex C-70 foam:
Description & Characteristics

A unique closed cell, cross-linked polymer foam that combines high stiffness and strength to weight ratios with superior toughness. It is non-friable, contains no CFCs, has negligible water absorption, and provides an excellent resistance to chemicals. A fine cell structure offers an excellent bonding surface that is compatible with most resins and manufacturing processes. It is ideally suited as a core material for a wide variety of light-weight sandwich structures subjected to both static and dynamic loads in service.

high strength and stiffness to weight ratios
good impact strength (highest elongation in class)
low resin absorption
high fatigue resistance
good fire performance (self-extinguishing)
sound and thermal insulation
non biodegradable
good styrene resistance

Hope this helps with the customer...

Thanks,
Bob

The dealer goes on to say:


"I know from talking with them in the past that they went to Airex coring in 2000. So all boats prior to 2000 were cored with End Grain Balsa. Prior to that (such as back in the 80’s or 70’s) Albin was building their boats overseas and not here in the US. I’m not 100% positive if they were coring the hull or if it was solid glass. The current employees in Rhode Island are not sure either – so it may take me some time to get an answer on that one.

So I’m not sure if I answered your question entirely, but I will say that in the almost 10 years we’ve been a dealership we’ve haven’t really seen any issues from our customers concerning the coring material. If anything, one of our customers said his life may have been saved by the cored hull. He was traveling 18 knots and hit a rock square and the boat did not take on water, did not sink, etc. Coast Guard/Surveyors involved felt that if the hull would have been solid glass, the impact would have caused some severe fracturing and it they felt that the boat probably would have sunk."

End of quote!!

That's about all I know about the subject. My thoughts about hull makeup was like many of you, that solid laminate hulls were better than cored hulls. I may have to adjust my thinking, especially when the Albin hulls are laid up via the vacuum bagging process.

Mike aka: Med2alfa

[mark bowerman]

The 27's are all solid glass hulls up to the rub rail. I would not buy a boat with a cored hull below the waterline and would have serious issues with any coring in the hull. I hate the balsa but you get what you pay for.

[RicM]

In preparation for our purchase (still ongoing, hope to close Jan 30) of a 28TE I read a book by David Pascoe called "Mid Size Power Boats". You can find it here:
http://www.yachtsurvey.com/mid_size_power_boats.htm
The website itself is quite valuable to get an extremely conservative point of view on boat design and construction.
Pascoe has an interesting point of view on boat hulls that I should not try to sum up here, but in essence he seems to feel that the concern over issues like coring and blisters are much ado about nothing. If a boat is well designed and built it will provide many years of good service regardless of whether the materials are the latest hi tech stuff or not. Bad design is a bigger enemy that balsa. I recommend the book highly. You may not agree with some of his assertions but he's a pretty smart, very knowlegeable guy.

[Elizabeth Ann]

I always thought Pascoe was against cored bottom boats. Obviously solid glass is better, but I have no problem with cored hulls - it just means you have more things to pay attention to during daily, weekly, and monthly inspection/maintenence.

See Dave Pascoe's thoughts on coring here:

http://www.yachtsurvey.com/structuralissues.htm

[med2alfa]

Hey Ric, glad you reminded me about Dave Pascoe's book. I have a copy around here somewhere and will have to dig it out and refresh. I've read a bunch of his boat reviews and get the same general impression that if a boat is built well it won't matter that much of what it's built.

Does anyone know for sure that the cored hull on the newer Albin 28,31, and 35's are built via the vacuum bagging method? I saw the process done to the cabin tops of the Nordic Tug here in Burlington, WA. and it is quite slick. It's supposed to make a lighter stronger core that completely saturates the fiberglass thereby reducing the chance of delamination.

[Donya]

Hi Mike,
My wife and I are from the Bellingham area and are working with the same dealer brokeraging our boat for us. They seam to be great people, I trust them.

Nice to here from some local people in our area out here!!

Don

[tomcat rio]

...i probably cored with balsa, right?

[DougSea]

...i probably cored with balsa, right?

That 'wood' be correct.

And as long as your through-hulls are properly mounted, as explained in the note from Albin at the start of this thread, you should never have a problem with it.

[Mariner]

Closed cell foam is very different than the stuff that was used in the 70's and early 80's in many boats. It is virtually impervious to water intrusion and the only area of concern is in delamination. When delamination occurs, you can get water in the voids between the glass and the foam. It will have a tendency to move around due to varying pressure on on the hull and will spread the delamination. However, if the hull is properly cared for, there little to be worried about.

Boston Whaler has been using closed cell foam in their hulls since the 50's. And although their method is different, and there are some problems with delamination and even water intrusion in the early hulls if they are extremely poorly cared for, they have maintained a impeccible record for quality over the years. I see no concern over the use of closed cell foam so long as it is bonded to the laminate before the laminate has fully cured.

However, it is true that any cored hull needs to have any holes or cuts in the outer and inner laminate repaired immediately, as water can erode the foam core over time, causing a loss of structural integrity.

[med2alfa]

Hi Mike,
My wife and I are from the Bellingham area and are working with the same dealer brokeraging our boat for us. They seam to be great people, I trust them.

Nice to here from some local people in our area out here!!

Don

Thanks for the howdy, Don. My wife and I, living in Anacortes, were up your way last week and looked at what Bellingham YS had in inventory. We really like the 35 TE, which they didn't have, but the 31 may work as well. Really want a single engine model. How about you? What stage of brokeraging are you at?

Mike

[tomcat rio]

http://www.sailingbreezes.com/sailing_b ... _hulls.htm

[med2alfa]

I always thought Pascoe was against cored bottom boats. Obviously solid glass is better, but I have no problem with cored hulls - it just means you have more things to pay attention to during daily, weekly, and monthly inspection/maintenence.

See Dave Pascoe's thoughts on coring here:

http://www.yachtsurvey.com/structuralissues.htm

I reviewed Pascoe's book and on page 109 he says: "The bottom line is that there is just too much risk involved with cored bottoms. Who needs it when a solid glass bottom will do just as well?" In the next paragraph he says: "Most of these problems can be solved by the process of vacuum bagging. This results in a higher glass to resin ratio which makes the hull even stronger."

Well I guess there's some comfort here for us Albin fans if they are indeed using vacuum bagging for their hulls below waterline.

Pascoe's thoughts on cored hulls related to the above yachtsurvey link were dated in 2001 or before. His book was written in 2003. Somewhere between the two dates he saw the light.

[Donya]

Mike wrote

Really want a single engine model. How about you? What stage of brokeraging are you at?

Mike

BYS is listing our current boat for sale. We have been looking at both the 28 TE and 31 TE. Our goal is to keep something that is fishable as we make a yearly trip up the coast to Prince Rupert area with a stop over in Rivers Inlet to visit family. Presently thinking used, but the boat show is in a few weeks.......

Don

[med2alfa]

Mike wrote

Really want a single engine model. How about you? What stage of brokeraging are you at?

Mike

BYS is listing our current boat for sale. We have been looking at both the 28 TE and 31 TE. Our goal is to keep something that is fishable as we make a yearly trip up the coast to Prince Rupert area with a stop over in Rivers Inlet to visit family. Presently thinking used, but the boat show is in a few weeks.......

Don

Same here. Will be at the show 25 & 26. The only Albin there will be the 28 plus a couple of Sabres. New is too pricy for my blood. I like to knock that first year depreciation off before buying.
We too like to fish the Rupert area. Haven't been up on our own bottom yet, just drive up and do a week on an overnight charter. We do a week trip to Port McNeill each year around first of August. Great time for 20 -30# Kings plus big Coho.
The 31 sure has more room for extended cruising. Not many around these parts, though. Good luck with your search.

Mike

[RicM]

I'm reviewing my "Pascoe" as well, it's been 6 months and that book is a lot to swallow in one reading. Now let me also say that I find a lot of his opinions a bit on the conservative side (and a bit cranky). According to David not much of value has been built or designed since the '80's, co-incidentally around the time he left the manufacturing end of the business. But he does specify a difference between cored "bottoms" and cored hull sides. Can someone speak with authority on the location of the coring in 28TE hulls? In the world of Pascoe, if I read him correctly, cored sides above the water line are OK.