New Project B25!

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Yannis
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Re: New Project B25!

Post by Yannis »

Tony,

The question is if by removing parts of this "stringer", as some of us have already done, is a compromise to the boat's integrity.
And if this can be repaired by the addition of glass layers in the area.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
Navatech

Re: New Project B25!

Post by Navatech »

Tony Meola wrote:As an FYI, Capt. Pat always said not to worry if the wood encapsulated in the glass rotted away. The stringer would still do its job as designed even with rotted wood.
I haven't had a chance to see how Bertram did things on the B31 but on the B46 the fiberglass Bertram put over the stringer is rather thin... If I had a similar problem I would certainly put some cloth and epoxy to strengthen the existing fiberglass... But, because these things are always relative to the size of the boat it's possible that the same fiberglassing on a smaller boat is sufficient without adding to it... After all, when the wood has rotted it's the U shaped fiberglass "stringer" that provides the strength...
Yannis wrote:The question is if by removing parts of this "stringer", as some of us have already done, is a compromise to the boat's integrity.
And if this can be repaired by the addition of glass layers in the area.
Yannis, the keel of any vessel is often compared to the human spine... IOW, it's the back bone on which everything else is build... Having said that, modern flat bottomed commercial vessels (which basically means everything from ferries through tankers through container ships) no longer have a built keel... The whole double bottom structure serves as the keel did in older designs... And, as always the proof of the pudding is in eating it... If I understand you correctly you did this several years ago... Assuming there aren't any cracks or other signs of stress you should be good...
Yannis
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Re: New Project B25!

Post by Yannis »

No cracks, no sign of stress.
It would be nice to hear from others who have also done this, if there were any problems.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
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CamB25
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Re: New Project B25!

Post by CamB25 »

I cut down that "keel" stringer aft of the battery compartment. Not expecting any problems.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
Tony Meola
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Re: New Project B25!

Post by Tony Meola »

Yannis wrote:Tony,

The question is if by removing parts of this "stringer", as some of us have already done, is a compromise to the boat's integrity.
And if this can be repaired by the addition of glass layers in the area.
Yannis

I doubt removing such a small section would create a problem, unless this one spot happened to be a very high stress point.
1975 FBC BERG1467-315
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JH_B28
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Re: New Project B25!

Post by JH_B28 »

Yannis wrote:No cracks, no sign of stress.
It would be nice to hear from others who have also done this, if there were any problems.
Yannis,

I did the same thing as you on my boat and don't think it would structurally compromise the hull in that area, at least in the B28. After I cut, I put a layer of fiberglass to level things out and give me "peace of mind". I'll let you know once i'm in the water again.


Regards!
Jorge E.
1973 Bertram 28'
Yanmar 4LH-STE's
Mitch
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Re: New Project B25!

Post by Mitch »

Hello all, have not been around for a while. I love this thread. I started my Bertram thing with a 1968 B25 sedan. Then went to a 1965 B31 Sportfish. In my 25 I cut out the whole drop down, left that keel piece, but capped it off in fiberglass so it could serve as limber, but seal off the gas tank to moisture and got an 80 gal tank in there and made a hatch to cover it, I also made a U-shaped cut out in front of the tank, for the step down into the cabin. And you could easily fit another 80 in the original gas tank bay, same method. I also filled all the voids in the hull outboard of the stringers and under the forward bunks with 500lbs of 8lb polyeurethane 2 part foam. What a huge difference in the way the boat rode and handled. If anyone remembers Trey from Texas I got that idea from him and I still have the original blueprints of the 25 from "Bertram" it shows where to cut all the holes to inject the foam, if anyone's interested. It changed the boat immensely. I never should've sold that boat, but I HAD TO HAVE A 31.... I rebuilt the original 165's made them freshwater cooled with late model alphas and that boat performed and handled great.. with 1-300 or a couple 175's your boat will b great. I have a 1962 B25 ex-sedan that was gonna b my last boat but not sure if I got another hull-up Reston in me...it's for sale if anyone's interested, its on CL Cape Cod. I'm into landyachting now rebuilding a1996 28' Safari Trek the Bertram of motor homes check it out. Enjoy your project, I miss my Bertram.
Mitch
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CamB25
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Re: New Project B25!

Post by CamB25 »

Thanks for contributing with real world results, Mitch. Gives me a little more confidence that this might work!
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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Joseph Fikentscher
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Re: New Project B25!

Post by Joseph Fikentscher »

Mitch,

I would love a copy of the blueprints.

Joe
Sea Hunt Triton 207, a step down, but having fun till my next Bertram!

[url]https://www.instagram.com/endurance_ber ... hl=en/[url]
Mitch
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Re: New Project B25!

Post by Mitch »

Anyone else that wants a copy,pm me an address I'll get copy off to you
Mitch
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Waytooslow
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Re: New Project B25!

Post by Waytooslow »

Are the blueprints digital or hard copy? if not digitalized can they be scanned? Todd
1963 B-25 Project (in process)
Atl. GA
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