Bertram 630 Sportfish Sinks?

SHAZAM! my point exactly, if you/builder fail in the execution and poor choice in materials, your product will fail? But the builder doesn’t know this until it starts to delaminate/fail… correct? That’s what’s wrong with this technology… yes? And rumour has it that Bertram now have a devise that’s picks this up…?

Marmot, aren’t you now giving the buoy and boat different velocities, and changing point of impact, and thus changing the scenario….? to answer the question, it would do some good damage, depending on where on the bow u drop the object. the same damage as we see….. I don’t think so IMO

far

also, and I think as of middle 2008 they changed the production manager at Bertram...?

far

Depends on the diameter of the bag of sand, and it's still an apples to oranges comparison. If I had a bag of sand of 200lbs that was 2 ft in diameter dropping on the deck from say, 16ft (1 second) the deck should hold even if the bag manages to stay intact. A basic sandbag though as used in industry will burst absorbing decellerational force in the process. However, calculating the forces imposed by each type of impact are different equation sets with a few common equations. The bouy strike scenario is a reasonably complex set of equations in considering mass and inertia of the bouy, velocity, bounce of the material (which has to take into account the structure and material of both impacting surfaces and the structural for resiliance before the structure starts to crumple and absorb force), drag of the bouy in the water to find the terminal decellerational value in Gs (basically working for terminal velocity to calculate the maximum force it can apply to the hull. The maximum force available to transmit, and that is a dynamic equation as it has a small amount of drag as it floats against the weight of the chain which has slack in it. so you have a acceleration value of both the chain and the bouy's inertia which is equally matched as a decellerational force in the boat as one pulls up the weight of the chain over the time required is the drag of the bouy, the drag increasing not only until the chain end is reached but also the terminal bouancy force available) and area of impact, the resistance value of the water and the vector of impact with force sheering in 2 vectors and the impact velocity. As you can see, the actual kinnetic energy available is dissipated and divided through multiple force vectors, and is limited to the inertia of the bouy take with the square route or the time of the decelleration to reach terminal drag (force).

The channel marker on a piling impact that you supplied is a much simpler set of equations because you can you can all the inertial values of the piling as basically infinite for all intents and purposes in this type of collision since the structure of the piling is of an overwhelmingly superior strength to the boat. The impact absorbtion deccelerational value is only the time and distance of, which will be minimal due to the leverage of the piling under the seabed, and force vector which in this case will be very near perpendicular to the initial impact point on the radius or the rail, required to flex (bounce value of impact) the piling and/or hull material to destruction. This is the weakest mode of force application for any composite layup and a very strong mode of fore application strength for wood. Since the wood won't bounce far, the fiberglass is going to absorb the vast majority of the damage.

Correct, the chief issue with any composite is that it quite often holds damage hidden until failure. Carbon Fiber is especially bad on this because it's failure mode is explosive. The only way you can test anything is radio graphically or ultra sonically and all of these processes requires a skilled technician to apply the test and interpret the results. (although there are some very expensive machines out there that make the interpretation pretty obvious.) Many of these materials show and suffer not from fatigue and visual degeneration as metal does, and that's what clues us in as to how bad the damage we've sustained is. In an equal force event with equal strength metal and layed up materials, if we have an impact that is 95% the value required for failure, we'll have visible damage and know we have to effect a repair, and how far the damage spread. With a layup composite we can have damage that takes 95% damage (decreasing strength to 5% undamaged value) to the substrate in delammination between layers and shatter cracks in the resin and never see the weak spot nor the spread of the damage. Typically we don't find most of these problems until destructive failure. "Eh, I scratched it on the dock, we can fix that with gelcoat" has been the root of more than one problem I've seen. That's why we design with composities to contain damages within an area and reinforce periodically so we can have a destructive failure without losing the whole vessel. This is one of the issues with composite aircraft as well.

Far, please refer to my post #383. I thoroughly check and test all products I use in my builds before I ever incorporate them into a yacht, end of story. I, as did everyone else who came across the core that Bertram has been using wrote the stuff off as foam not even worthy of use by a florist in a floral arrangement. If you don't do R&D then follow up with quality control then all you're doing is setting yourself up for failure. In the case of bertram since ferretti took over there's been virtually no R&D whatsoever. During it's heyday, bertram would tank test hulls, build prototypes that were extensively tested then once the designs and models were proven, then and only then would production start. Even then the first 3 or 4 boats were built by the prototype shop before they were handed over to the production line guys for production building. Do you think that exists today? When the new 54 was sea trialed for the first time and it's poor handling and sea keeping characteristics were discovered, there were already several other 54's on the production line awaiting completion. OOPS!

Folks over at Bertram, see what saving money on core cost you? There's a reason why DIAB and SP core materials cost more, not to mention that they have RINA, ABS, LLOYDS and ISO certification. Ever wonder why the garbage core from Hialeah has none of those certifications?

I am a Tool and Die Maker, not too much experience with Fiberglass. We did machine Phenolics and Glass filled plastics like G10. Most of what we machined were Hastelloys and Monels, Aluminum Bronze and related when parts for the marine industry / Alameda Naval station came in for rework or new manufacture. This was back when the military was still welcome in the San Francisco Bay Area, in the 70's and 80's.

Ive seen general quality and craftsmanship slowly spiral downward the last decade or so, especially outside high production arena, companies are just chasing each other to the bottom of profit / loss ratios. The quality just isn't there any longer for the average product.


If you Google "Bertram boat Failure", there are a dozen boats pop up with horror stories, and people swearing off this particular boat / type of build. There is a serious problem with the manner these boats are now built, and the company needs to address it, or the company will fold.


Buying quality is the best defense. the marginal players will lose market share and be forced out, those that invest in quality materials and their employee's training will still be around.

Shazam and henning have some good info here. I will ad a 1/2cents worth

A core is used inplace of a solid laminate for weight savings mostly. That means you are substituting an inferior or lesser solid substance to take up the center space in a formerly successful solid laminate. I think like henning and shazam and the surveyor d pascoe that if the boat companies want to sacrifice the integrity of a solid hull with a core then they have to use better quality{ both in materials and in human talent!} in the small amount of fiberglass reinforced resin construction. I also think the resin savings is getting dangerous in resin dry laminates ! This weight saving game for speed is sacrificing integrity.Also because of the growing posibility of laminate damage because there is so little in todays boat construction. A gelcoat manufacturer has developed a gelcoat that changes color if it get deflected in an impact. I am not saying this is the answer !!but they know they have a problem with the light weight building going on today. Shazam some good info on the early R&D days of bert and that core they are using today. I could share some of the same {hands on} concerning the NO1 builder today.

Somewhere in those thousands of words you have made my point. The picture of the skewered boat illustrates how a well made structure will absorb the energy of a high speed impact with an "immovable object."

If a well constructed boat hit a "moveable object" of relatively low (200 lbs) mass the damage should have been very much less than we see. The energy in the system was probably not much different than the skewering event but the buoy was free to move and dissipate considerable energy. The Bertram obviously absorbed a great deal of energy but the time (deceleration) had to have been relatively long as the occupants were not killed or seriously injured by a rapid stop.

The bottom line is that the damage shown is far in excess of what one would expect in a collision with a buoy of the type and size shown unless the boat's structure itself was far weaker than that of the skewered boat.

For the spin masters over at Bertram, if a movable floating buoy caused your prized battlewagon to disintegrate, then how would you expect the 630 to have reacted in this instance...




This a mark IV 46 Bertram built in the mid 90's when bertram was probably at its weakest financially, yet somehow they managed to build a boat that was stronger than most other production boats of its size. IMO, the longer bertram sticks to the buoy impact causing the boat to fall apart, the worse they look.

Who is the NO 1 Builder?

Do you know what caused this?

I'd guess asleep at the helm or he may have just needed to bottom paint and didn't want to pay for a haul.

Viking inthe bertram hatteras viking class>

At one time they were solid glass hulls below the waterline chine.Bill healy was very adamant about a fiberglass boat that was like steel. Now they are balsa coring the hull bottom and still using polyester resin? There old hands on R&D department was very good at overbuilding just in case. and they really had no true engineers watching or advising. just dedicated hands on viking workers and no cad cam. thats where they came from. and thats what made them respected.

So how do all of us sportfish owners, know if one day our boat will have similar failures. I own a 04 Egg Harbor 43', this whole thing makes me nervous. Yea, before I bought my boat I had a surveyor go thru it extensively, the hull was dry and he sounded it and I got the green light? Is that it, are there tell tale signs, that there might be problems. I guess if all of a sudden there are things like door jamb misalignments, that might be cause for concern? But how do so many of us really know?

Reputation.
BTW, Welcome to YF neighbor.

Yeah, you've come across the main detractor to composite construction, detecting low grade partial matrix failure and determining the damaged strength remaining. That's why the manufacturers reputation has to be very strong. It's also why I prefer metal or wood.

fiberglass has far fewer issues then either wood or metal. As far as a survey goes, this is where the surveyors (some not all) IMO haven't caught up with the construction techniques. I think any survey on a cored hull boat that doesn't include thermal imaging and core sampling is just about worthless whether the boat is new or used.

From the layman's perspective, if that buoy punctured upwards through the hull side and cause the deck to separate (about as likely as Santa, the Tooth Fairy, and the Easter Bunny coming over to Christmas dinner) then wouldn't that wholly unscathed reflector act as an arrowhead or harpoon flue, lodging itself in the boat?

If it did that even momentarily, then one would think there would be at least SOME mark on it to indicate such an abrupt entry into (and subsequent forcible exit from) the side of the boat.

Bertram's story does not pass the sniff test. I have no dog in this fight, and am not out to bash Bertram, only to question how their boats can be immune to the laws of physics on one hand, yet are so adversely affected by seemingly slight collisions on the other.

Sir Isaac Newton would have to rethink his laws of motion based on Bertram's claims, particularly the third. Since others are *******izing, misinterpreting, and misapplying the second law already, I will refrain for belaboring this point.