Check out this boat, it's was just built.
Moderators: CaptPatrick, mike ohlstein, Bruce
Hello Rawleigh, You ask and I'll try to answer, but first I am not involved with the workings of the website but I did pass on the information you all provided and that is being resolved. As I understand it the web designers used placeholder pictures because completed pictures of the Nassau were not available and I shouldn't have included the web address in the clip until those changes were made, as the President of the company has repeatedly told me, all day. If I can answer any questions about the boat I would be happy to.
yachts101 good luck with your boat. Some of you guys need to take a deep breath and relax. I have posted many many pictures of Bertrams over the years. Most of them I took myself while your boats were in full PUBLIC view. Gee the guy said he was sorry and explained the Bertram pics were "placeholders". Good enough for me.
Good Luck and I hope the boat is a hit because it is a really nice looking boat. Can't wait to see one in person.
Good Luck and I hope the boat is a hit because it is a really nice looking boat. Can't wait to see one in person.
That's the truth.Charlie wrote:yachts101 good luck with your boat. Some of you guys need to take a deep breath and relax. I have posted many many pictures of Bertrams over the years. Most of them I took myself while your boats were in full PUBLIC view. Gee the guy said he was sorry and explained the Bertram pics were "placeholders". Good enough for me.
Good Luck and I hope the boat is a hit because it is a really nice looking boat. Can't wait to see one in person.
Trying to sell something?I have posted many many pictures of Bertrams over the years
Design a car to look like the corvette and put a picture of a corvette up to sell it and see how fast GM lawyers get a hold of you.
Theres a legitimate complaint and concern among folks here who realize the differences between the two boats and those who are not as knowlegable might think that the new boat is just like the 31 only new.
While I don't really have a clue, I would consider that false advertising.
Wasn't one of the sponsors making a replica of the 31 a few years back? 31 classic or classic 31 or something to that effect.
Hell guys, I would hope the Nassau 32 takes off, it would only increase the value of our boats as we have the originals. They would be selling knockoffs at 350 grand. Better or not they would be knockoffs just like The new Thunderbird, The new Mustang, etc. except we are told they are retro instead, call it what you like.
As to the pictures, 101, if they are just placeholders it's understandable but linking us to the site with them on there was a boo boo.
As to the performace specs, I know you are comparing to a 31, why the false information? Exactly what 31 Bertam cruises at 12 knots and burns 50gph? Your numbers are excellent but they are diminshed by falsehoods. Or did I miss something.
Carl
Hell guys, I would hope the Nassau 32 takes off, it would only increase the value of our boats as we have the originals. They would be selling knockoffs at 350 grand. Better or not they would be knockoffs just like The new Thunderbird, The new Mustang, etc. except we are told they are retro instead, call it what you like.
As to the pictures, 101, if they are just placeholders it's understandable but linking us to the site with them on there was a boo boo.
As to the performace specs, I know you are comparing to a 31, why the false information? Exactly what 31 Bertam cruises at 12 knots and burns 50gph? Your numbers are excellent but they are diminshed by falsehoods. Or did I miss something.
Carl
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Frankly, I don't buy into the "Place Holder" story... Most webmasters use an image like "Image not available" or simply mask the place holder from view by the browser until an image is available.As to the pictures, 101, if they are just placeholders it's understandable but linking us to the site with them on there was a boo boo.
Also, the images of the real B31s were not photographed by whoever, within the Nassau 32 staff. They were extracted directly from the Internet, in large part from this website. There's a real big difference between how Nassau 32 is using these images & how images are used showing the turnout of a rendezvous, as Bruce pointed out.
Gee, I knew that a Tampa minute was longer than a New York minute, so obviously "immediately" surely would take a few more moments down south. But we're in day three now and Chimera, Buddy Boy, and all of the rest of our B31s are still there... Oh, I get it.... "Nassau" as maybe in "Bahamas"... Guess we'll just have to wait a few more weeks...Gentlemen, the pictures of the other boats, not the Nassau 3204 are being removed from their website immediately.
Again, I'm not knocking the boat, but the website... Apples n' oranges... The apple looks great, but the orange is starting to grow green hair.
Br,
Patrick
I think its a good thing to be copied.its flattery..
There are soo many funny looking new boat styles nowadays that are high $.. & wont last.
The original is made more valuable. the car reference is right on.
but I think the wrong facts on our performance should be corrected. & I know they wont be riding as good as ours..Get that straight &.
Hope they succeed..just my 2cents
Wayne
There are soo many funny looking new boat styles nowadays that are high $.. & wont last.
The original is made more valuable. the car reference is right on.
but I think the wrong facts on our performance should be corrected. & I know they wont be riding as good as ours..Get that straight &.
Hope they succeed..just my 2cents
Wayne
I think is is great to have a 'new' option. Reminds me of the outfit in British Columbia that have the 20 and 25 foot hull mold.
I would offer the hull cored on the hull sides and solid glass on the bottom if the buyer desired.
Most likely they would do this in solid fiberglass if one wanted.
There was on shot of the starboard stern by the hawse pipe and the liner looked to have considerable amounts of glass in it.
Looks good!
Good luck I say.
Ian.
I would offer the hull cored on the hull sides and solid glass on the bottom if the buyer desired.
Most likely they would do this in solid fiberglass if one wanted.
There was on shot of the starboard stern by the hawse pipe and the liner looked to have considerable amounts of glass in it.
Looks good!
Good luck I say.
Ian.
CaptPatrick wrote:Frankly, I don't buy into the "Place Holder" story... Most webmasters use an image like "Image not available" or simply mask the place holder from view by the browser until an image is available.
Br,
Patrick
Capt Pat, I didn't say I bought into it either. I said "it was understandable", maybe just looking for an out, maybe the truth, maybe the first thing that came to mind, maybe an outright lie, whatever, just have the pics pulled and tidy up the specs. I would love to see what "improvements" they made to the best boat ever built.
Last edited by Carl on Dec 13th, '08, 14:15, edited 1 time in total.
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Carl,
Wasn't callin' out your acceptance of the term, but rather that place holders are a valid way of coding for future implants, but that there are ways to do it correctly. In this case, it's obvious the technique was not only used incorrectly, but also less than honestly...
At any rate, I'm pretty much done with whippin' a dead horse and movin' on to more important issues.
I would, though, very much like to hear from yachts101 with more info on their new boat. Construction techniques, problems run into & solved, material choices, such as: Which foam core, thickness of the skins & core, which fabrics were chosen, etc... Already know they're using a cutting edge technology for theit resin choice.
Not lookin' for trade secrets, just the usual stuff any boatbuilder will gladly offer up when ask. Anybody with a good product should be proud of it & be ready to talk your ear off about it.
Come on, yachts, talk to us! No need to involve yourself with more apologies for the website blunders, just give us some boat meat to chew on. You already know what carnivores we are...
Br,
Patrick
Wasn't callin' out your acceptance of the term, but rather that place holders are a valid way of coding for future implants, but that there are ways to do it correctly. In this case, it's obvious the technique was not only used incorrectly, but also less than honestly...
At any rate, I'm pretty much done with whippin' a dead horse and movin' on to more important issues.
I would, though, very much like to hear from yachts101 with more info on their new boat. Construction techniques, problems run into & solved, material choices, such as: Which foam core, thickness of the skins & core, which fabrics were chosen, etc... Already know they're using a cutting edge technology for theit resin choice.
Not lookin' for trade secrets, just the usual stuff any boatbuilder will gladly offer up when ask. Anybody with a good product should be proud of it & be ready to talk your ear off about it.
Come on, yachts, talk to us! No need to involve yourself with more apologies for the website blunders, just give us some boat meat to chew on. You already know what carnivores we are...
Br,
Patrick
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I managed to flip my1962 13' Whaler off the trailer behind my Lincoln Mark 4 (dark green coupe with white leather interior, aiiiiieeeee!!) going 97 mph down the interstate.....bounced a couple of times, tore the motor off and split the hull down the middle and on one side.....back on the trailer, took her home.....three come-a-longs, some rope, some fiberglass tape and resin and she's good as new.....Da Judge is her Steward now, heard he put her in his hangar during Gustav's visit to Galveston and she, trailer & all, ended up on the wing of a WW2 bonber.....can't kill 'em.
UV
UV
Yep, fully cored hulls are great, aren't they? I am absolutely the happiest person I could be owning this original B31!! The reason I bought mine is my father had one, and I know that boat and how it leaves you feeling EVERY time we used it. That is the same pride I have now, owning one of my own. That is what every B31 owner here has, and should except no imitation! Rocky.
Well, the Bertram pics are down and have been replaced with the Nassau pics...their site makes sense now. visually that is.
http://www.yachtworld.com/boats/1974/Be ... ted-States
Thats gotta be the niceset B28 I've seen... Or maybe a working prototype for the Nassau29? Nice work either way...
SO, I think there's only one reason why the they're treating the "B" word like a bad case of the clap, they're not sure if they're quite legal with all this. Ouch.
Strange how I perceived that backassward. I guess following the rules makes you seem a bit shady at times... sorry Yachts.As long as they, in no way refer/infer to the word "Bertram" or ever display the Bertram logo, the Bertram company will not be concerned with their endeavor.
Thats what I was thinkin... Pretty nice glasswork. Is this is one of their latest as well?I think that he would do better as a responsive, English speaking, Cabrerra
http://www.yachtworld.com/boats/1974/Be ... ted-States
Thats gotta be the niceset B28 I've seen... Or maybe a working prototype for the Nassau29? Nice work either way...
I don't know what the world may want,
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
The ad says totally renovated, everything new BERTRAM 28.Buju wrote:Thats what I was thinkin... Pretty nice glasswork. Is this is one of their latest as well?
http://www.yachtworld.com/boats/1974/Be ... ted-States
Thats gotta be the niceset B28 I've seen... Or maybe a working prototype for the Nassau29? Nice work either way...
Harv
That was just a lttle tongue-in-cheek humor Harv...Or maybe a working prototype for the Nassau29?
...but there might be some truth to it. If they made a mold for the 31, wouldn't think they'd have much trouble doing the 28.
By the way, the mold for their 31 (N32) looks like a one piece mold, and the hull seems to have the same tumblehome as the B31?
How'd they done that?
I don't know what the world may want,
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
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Buju,
They're using a two piece hull mold just the way that Bertram did...
The image of their mold, at the point that it was being constructed, shows the joint line down the center line. The rectangular pockets that you see are the registration keys. When the mold was finished, the flange would have been drilled every few inches to accept large through bolts. By the way they've designed their mold, with the registration pockets, they may be clamping rather than bolting the two halves together.
They're using a two piece hull mold just the way that Bertram did...
The image of their mold, at the point that it was being constructed, shows the joint line down the center line. The rectangular pockets that you see are the registration keys. When the mold was finished, the flange would have been drilled every few inches to accept large through bolts. By the way they've designed their mold, with the registration pockets, they may be clamping rather than bolting the two halves together.
Craig,Craig Mac wrote:Looking through the gallery pics--it looks like they made at least two--one with front windows and one without.
Look again at the gallery pics or better yet, click on the link I provided about 3 or 4 posts up the page. The boat with the front windows is a Bertram. Look at the side pilaster. Notice the Bertram bridge step with the eagle logo inside it? Also, look at the gallery pic of the boat head on and notice the Bertram chock on the bow. The only boat it seems they made has a green hull. The other boat has a blue hull, and that's a Bertram.
Harv
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Guys
I am not sure Yachts 101 is the builder. He posts on Boat Diesel and at one point when I had posted a question for Tony Athens, Yachts 101 jumped in and posted some pics that helped answer my question.
I am just not sure what their involvement is, but he should let us know if he is an investor, or just hoping to sell them.
I am not sure Yachts 101 is the builder. He posts on Boat Diesel and at one point when I had posted a question for Tony Athens, Yachts 101 jumped in and posted some pics that helped answer my question.
I am just not sure what their involvement is, but he should let us know if he is an investor, or just hoping to sell them.
I'd love to know what you're using as the core material...my guess would be one of the "honeycomb"-like materials...
Are you guys also vaccuum bagging the hull?
Is that B28 one of your (their) projects as well?
Are you guys also vaccuum bagging the hull?
Is that B28 one of your (their) projects as well?
I don't know what the world may want,
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
But a good stiff drink it surely dont,
Think I'll go and fix myself...a tall one.
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Errr...yachts101 wrote:I am the project manager on this build.
Ask me any questions you want and I'll answer the ones I can.
CaptPatrick wrote:Construction techniques, problems run into & solved, material choices, such as: Which foam core, thickness of the skins & core, which fabrics were chosen, etc... Already know they're using a cutting edge technology for theit resin choice.
Not lookin' for trade secrets, just the usual stuff any boatbuilder will gladly offer up when ask. Anybody with a good product should be proud of it & be ready to talk your ear off about it. (from previous page)
"The 31 Sportfisherman (believe they speak of our babies) is truly
a classic, and with thousands sold . . ."
From their website, maybe a few more correct facts would help their case.
"with thousands sold"???? Not the whole production run of B31's was "thousands." and the sportfish? How many?
If I had 350 beans in my jeans and wanted a new "31" I'd find the best hull I could scrounge for next to nothing and either do it myself (Gee that's what I did) or get an expert like Pat and say here's the carcass make me a boat. Probably less than 350 (or not) but I'd have an original with no cored hull or anything that might be construed as deceptive and a boat that looks fabulous, takes more of a pounding than my old frame will and has all the contemporary features, not a pretender.
Not a particularly good foot to get off on when dealing with a bunch of "finatics." If I were an Arab I'd be throwing shoes.
a classic, and with thousands sold . . ."
From their website, maybe a few more correct facts would help their case.
"with thousands sold"???? Not the whole production run of B31's was "thousands." and the sportfish? How many?
If I had 350 beans in my jeans and wanted a new "31" I'd find the best hull I could scrounge for next to nothing and either do it myself (Gee that's what I did) or get an expert like Pat and say here's the carcass make me a boat. Probably less than 350 (or not) but I'd have an original with no cored hull or anything that might be construed as deceptive and a boat that looks fabulous, takes more of a pounding than my old frame will and has all the contemporary features, not a pretender.
Not a particularly good foot to get off on when dealing with a bunch of "finatics." If I were an Arab I'd be throwing shoes.
Mikey
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
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Mikey - most of us agree that 1860 B31s of all five models were the production run from 1961 to end of regular production after the 1983 model year, and then the 23 Silver Anniversary models built in 1986 and that's it.
I wonder is these guys have any connection or have consulted with the Classic 31 guys in WPB? Some of John & Ray's ideas were pretty good, such as the elimination of the molded in toe rails, etc.
UV
I wonder is these guys have any connection or have consulted with the Classic 31 guys in WPB? Some of John & Ray's ideas were pretty good, such as the elimination of the molded in toe rails, etc.
UV
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Nic,
What you're looking at is the exterior of the hull mold, and appears to be only the skin layer over the orange tooling gelcoat. Hopefully, we'll someday get to see the actual hull lay up on a production part...
Generally, large molds are constructed with a fairly thin skin, then heavily reinforced with coring, followed by another fiberglass skin. Then the support ribbing, usually plywood and/or steel tubing, is configured & glassed in place. All done in place while on the hull plug.
This technique allows the mold to become very strong & rigid, but because of the thin fiberglass/resin inner skin, there is very little shrinkage or future distortion to the face of the production mold.
Typically, a finshed hull mold exterior will look similar ro this... (Obviously a sail boat hull in this case.)
Below is a rather low quality image of the 37' Ocean Yacht hull mold. Notice the 2 rolling cradles, which allow the mold to be rocked from one side to the other for ease of layup.
Br,
Patrick
What you're looking at is the exterior of the hull mold, and appears to be only the skin layer over the orange tooling gelcoat. Hopefully, we'll someday get to see the actual hull lay up on a production part...
Generally, large molds are constructed with a fairly thin skin, then heavily reinforced with coring, followed by another fiberglass skin. Then the support ribbing, usually plywood and/or steel tubing, is configured & glassed in place. All done in place while on the hull plug.
This technique allows the mold to become very strong & rigid, but because of the thin fiberglass/resin inner skin, there is very little shrinkage or future distortion to the face of the production mold.
Typically, a finshed hull mold exterior will look similar ro this... (Obviously a sail boat hull in this case.)
Below is a rather low quality image of the 37' Ocean Yacht hull mold. Notice the 2 rolling cradles, which allow the mold to be rocked from one side to the other for ease of layup.
Br,
Patrick
Last edited by CaptPatrick on Dec 18th, '08, 19:39, edited 1 time in total.
Guys-
I read the replies on cored hulls, and had some of the same thoughts. Today, I spent the day tooling around the lab at my sons school to see what my son was working on (URI, my son is going for a masters in ME.) One of his buddies projects (Not my sons project unfortuunately) is a Navt funded research project looking at foam cored fiberglass composite structures, and testing the material against various loads including bullets ect. All I can say is I have a new appreciation on how light and strong you can make thses structures. I would think with a proper vacuum infusion process you could bond the glass properly to the foam. Anyway, the navy is looking at this for a strong light material for some sort of watercraft. They key element of the research seems to be the foam, as I saw many ytprd of composite foam structures.
Anyway...fuel for thought. Maybe Foam cored isn't so bad afterall.
As an aside...Randall may apreciate this. My son is trying to spin up some variation on this for a possible application for surf baord construction. Of course that industry does not have the deep pockets of the defense industry....so I'm not sure there is any grant moeny.
I read the replies on cored hulls, and had some of the same thoughts. Today, I spent the day tooling around the lab at my sons school to see what my son was working on (URI, my son is going for a masters in ME.) One of his buddies projects (Not my sons project unfortuunately) is a Navt funded research project looking at foam cored fiberglass composite structures, and testing the material against various loads including bullets ect. All I can say is I have a new appreciation on how light and strong you can make thses structures. I would think with a proper vacuum infusion process you could bond the glass properly to the foam. Anyway, the navy is looking at this for a strong light material for some sort of watercraft. They key element of the research seems to be the foam, as I saw many ytprd of composite foam structures.
Anyway...fuel for thought. Maybe Foam cored isn't so bad afterall.
As an aside...Randall may apreciate this. My son is trying to spin up some variation on this for a possible application for surf baord construction. Of course that industry does not have the deep pockets of the defense industry....so I'm not sure there is any grant moeny.
Giff
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Unquestionably, with proper design, choice of materials, modern techniques, such as vacuum infusion, resin transfer molding (RTM), autoclave curing epoxies, & epoxy pre-impregnated laminates (pre-pregs), there is no doubt that a cored hull can be produced that out performs any single skin hull.Giff wrote:Anyway...fuel for thought. Maybe Foam cored isn't so bad afterall.
The problem is that 98% of the boatbuilders just don't have the access, money, or expertise needed to make such a hull. Also, from a bottom line mentality, not many of the potential boat buyers would be willing to fork over the extra bucks for quality that rivals that of the Aero Space Industry.
But even the average boatbuilders have come a long way since the 60s, 70s, and even 80s. Materials like vinylester, biaxle fabrics, carbon fiber, Kevlar & other aramid fabrics, such as Nomex and Technora are making it possible to build far stronger & lighter composite products.
An awful lot of the bad press on cored hulls came from, (and justifiably so), early manufacturers who were using polyester resin, 0/90º weave fabrics, and coring with materials like balsacore & rigid closed cell foams.
And it's not like someone can just dump all these high tech materials into a bucket and have a good product. A lot of real high tech designing and engineering have to be accuretly blended in to acheive that high level of quality.
U.S. Military & Aero Space account for almost all of tenhnological advances over the past 4 decades...
Br,
Patrick
U.S. Military & Aero Space account for almost all of tenhnological advances over the past 4 decades...
Capt. Patrick-
Amen...I knew you were on board when I met you! Yup could not agree more...and worked on a lot of it along the way. I had this conversation with Jr. this afternoon, and he also concluded without the military there would be very little real research going on in the enginnering department where is working and studying. Nice to see that academia has not poisened the young lads mind.
(Ok, a couple of days ago I posted that I worked in the auto industry...but before that, nearly 17 years in the defense industry...may have to head back in that direction again. ( A little afraid beacuse of our new president elect.))
Capt. Patrick-
Amen...I knew you were on board when I met you! Yup could not agree more...and worked on a lot of it along the way. I had this conversation with Jr. this afternoon, and he also concluded without the military there would be very little real research going on in the enginnering department where is working and studying. Nice to see that academia has not poisened the young lads mind.
(Ok, a couple of days ago I posted that I worked in the auto industry...but before that, nearly 17 years in the defense industry...may have to head back in that direction again. ( A little afraid beacuse of our new president elect.))
Giff
Capt Pat,
Thanks...I thought I saw a gun. Imho you want to save weight, hand lay-up...you want strength...hand lay-up...you want longevity...
Btw, got a new avatar I'm going to email...helicopter shot.
Best wishes for Christmas to everyone, you too Yachts!
I had a look at your web-site and what you've got looks like a fun project.
Nic
Thanks...I thought I saw a gun. Imho you want to save weight, hand lay-up...you want strength...hand lay-up...you want longevity...
Btw, got a new avatar I'm going to email...helicopter shot.
Best wishes for Christmas to everyone, you too Yachts!
I had a look at your web-site and what you've got looks like a fun project.
Nic
Hull No. 330 1963 SF "Tennessee"
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Oh boy.......... Divinycell is a good type of foam for a lot of cored items, like bulkheads, engine boxes, coaming panels, decks, house facing & house tops.
But, for a cored hull? No way.... Divinycell is a rigid closed cell foam. It has little impact resistance and next to zero memory. When you smack into something, a rock, reef, log, or other water hazard, the fiberglass skin will deflect and the Divinycell core will crush. The fiberglass pops back and leaves a void at the point of impact.
Hit something hard enough to deflect all the way to the inner skin and the sub-surface cells can rupture, which just destroyed the glass to foam bond there too. Hard flexing of the hull in heavy seas can do the same thing.
Try laminating two fiberglass skins over a section of Divinycell. Let 'em cure to full strength. Now catch the skins with your fingernails and pull. The Divinycell will fail at the surface bond and you'll peel the skins right off. It's not a matter of bond strength, fiberglass to foam, it's a matter of core weakness. I can do it with polyester, vinylester, or epoxy...
Take a piece of Divinycell and you can crush and crumble it with your fingers. H60 on the left & H80 on the right. Can't do that with Corecell, Klegecell or Airex...
I have personally seen, and repaired, several Divinycell core hull failures. Believe me, it doesn't take much of an impact to crush Divinycell.
Corecell, Klegecell or Airex are the principle foams that can be considered for producing a cored hull, because they are highly impact resistant, more plastic & therefore have a memory, and won't easily delaminate from the fiberglass.
Damn yachts, we sure were hoping you were going to tell us you were usin' the good stuff. Kinda' negates the fact that your using high tech vinylester resin... Glue is only as good as what you glue it to.
But, for a cored hull? No way.... Divinycell is a rigid closed cell foam. It has little impact resistance and next to zero memory. When you smack into something, a rock, reef, log, or other water hazard, the fiberglass skin will deflect and the Divinycell core will crush. The fiberglass pops back and leaves a void at the point of impact.
Hit something hard enough to deflect all the way to the inner skin and the sub-surface cells can rupture, which just destroyed the glass to foam bond there too. Hard flexing of the hull in heavy seas can do the same thing.
Try laminating two fiberglass skins over a section of Divinycell. Let 'em cure to full strength. Now catch the skins with your fingernails and pull. The Divinycell will fail at the surface bond and you'll peel the skins right off. It's not a matter of bond strength, fiberglass to foam, it's a matter of core weakness. I can do it with polyester, vinylester, or epoxy...
Take a piece of Divinycell and you can crush and crumble it with your fingers. H60 on the left & H80 on the right. Can't do that with Corecell, Klegecell or Airex...
I have personally seen, and repaired, several Divinycell core hull failures. Believe me, it doesn't take much of an impact to crush Divinycell.
Corecell, Klegecell or Airex are the principle foams that can be considered for producing a cored hull, because they are highly impact resistant, more plastic & therefore have a memory, and won't easily delaminate from the fiberglass.
Damn yachts, we sure were hoping you were going to tell us you were usin' the good stuff. Kinda' negates the fact that your using high tech vinylester resin... Glue is only as good as what you glue it to.
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I despise divinycell, I have used it 2 times, once was for a light weight race hatch, I vow to never use it again.
I do like airex core, but no one ever wants to pay for it, when given the choice people always go for end grain balsa instead- which again when properly installed and maintained could very well last forever.
I do like airex core, but no one ever wants to pay for it, when given the choice people always go for end grain balsa instead- which again when properly installed and maintained could very well last forever.
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Now there's my premier product to hate...end grain balsa instead- which again when properly installed and maintained could very well last forever.
I've seen far more rotten and water logged balsa to ever consider it as a core choice. Anything flat and horizontal is doomed as soon as a breach happens. Screws are probably the biggest culprits for water egress. Even a screw bedded with 5200 is going to leak sooner or later. The next biggest culprit is hatch & deck seams. Glasstech used to, maybe still does, use balsa core for their B31 decks. The component fiberglass parts come out of a mold, then they would/do goop in end grain balsa, and throw a couple of layers of CS mat over the balsa.
I worked on an old 46' Post that the whole house was balsa core and the boat had a very pronounced list to starboard. When I started cutting out a bigger ladder way to the bridge, (owner was a BIG boy), I found out why the list... Whole house was soaking wet and the water was draining to the starboard side. Was like cutting into Niagra Falls.
Every one of their deck systems that have the balsa is sucking in water from failing seams between the molded part and the fg mat bacling.
I've repaired so much rotten balsa that it gave rise to my "trail mix" formulation of resin, cabosil, micro baloons, and vermiculite.... And also gave rise to my tip on Hardware Mounting in Composites.
Balsa in a hull core would be the kiss of death!
I actually like Divinycell, but ya' got know where, when. how to use it. At least it won't get saturated with water and rot... I use it primarialy for non-load bearing bulkheads and cored doors. And then I'm usually laminating both sides with heavy Formica & thickened epoxy.
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its as simple as removing the balsa from mounting points, its not the core that fails- its humans that start the process then mother nature takes over.
when you have a 10-20 year old boat with rotted balsa core its super easy to see how it got that way and repair it so it wont happen again, for light weight and strength balsa is king- and the core by which all composite cores compare themselves to achieve in terms of stregth and light weight.
custom building interiors is one thing, but when you have a regular customer who has some bad core from a poorly sealed windless or bow railing he does not want to pay the extra for a foam core in his 20 year old cruiser, give him his balsa back- remove it from mounting areas and he will be happy as long as no drills other holes in the core.
btw- I hate formica!
when you have a 10-20 year old boat with rotted balsa core its super easy to see how it got that way and repair it so it wont happen again, for light weight and strength balsa is king- and the core by which all composite cores compare themselves to achieve in terms of stregth and light weight.
custom building interiors is one thing, but when you have a regular customer who has some bad core from a poorly sealed windless or bow railing he does not want to pay the extra for a foam core in his 20 year old cruiser, give him his balsa back- remove it from mounting areas and he will be happy as long as no drills other holes in the core.
btw- I hate formica!
Well said on Divinycell Capt. Pat.
Yachts, glad to hear you are hand-laying, but you got a problem. Easily fixed though, the design is all about a low centre of gravity, solid hull around past the chine, cored above.
You will find that dark hull colors & Divinycell don't go together either. You will also find that Divinycell know all this so start collecting your paperwork and tighten up on your evidence of the claims made for the product by the supplier so you can give them the bill.
The two prototypes can be destruction tested, though at this stage another tax write-off probably isn't a priority.
Did you put more head-room in the cabin?
Nic
Yachts, glad to hear you are hand-laying, but you got a problem. Easily fixed though, the design is all about a low centre of gravity, solid hull around past the chine, cored above.
You will find that dark hull colors & Divinycell don't go together either. You will also find that Divinycell know all this so start collecting your paperwork and tighten up on your evidence of the claims made for the product by the supplier so you can give them the bill.
The two prototypes can be destruction tested, though at this stage another tax write-off probably isn't a priority.
Did you put more head-room in the cabin?
Nic
Hull No. 330 1963 SF "Tennessee"
- CaptPatrick
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