Hull Quality and Desirability

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Jareb
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Hull Quality and Desirability

Post by Jareb »

I'm new to this forum. I owned a 31 FBC which I sold about 7 years ago and have regretted it since. I am currently looking to purchase another 31. I have heard that the earlier 31's were built a little "heavier" in the hull and that they are more desirable than later ones. Can anyone comment on the validity of this statement and where the date cutoff might be for the "better" built 31's; if it is in fact true.
Thanks
John
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scot
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Post by scot »

I'm no 31 historian and can't help you with the lay up thickness question....however I believe the 31's came with different engine box / space options and if I were looking for a 31 I would find one with the "big box" option. I would think the bigger boxes would be easier to repower and provide you with more repower options.

You should have you pick, there is a bunch of them out there for sale. Just go to usedboats.com and take your pick.

Good Luck
Scot
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
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randall
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Post by randall »

its true that earlier hulls are thicker....up to mid 60'si think...patrick will know ....and theres some mil spec hulls also....but they didnt make any weak ones
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JP Dalik
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Post by JP Dalik »

You need to be careful how early a boat you get. Some very early hulls continued to shrink and the gelcoat got a kind of alligator skin to it. No matter what you do short of gel pealing the boat the skin creeps back.
The later boats experienced a lifting strake change which dried them up a bit and helped them perform better. Along with the strake change they were lighter (not Ocean Yacht scary lighter but lighter)
The mid 70's boats include most of the hull and fiberglass adjustments. I do not know of any that have broken the hull.
Expect the bulkheads to be delambed and the wood to be rotten in an original boat, but the hull will always be just fine. There is nothing you can't fix with money and time.
KR


JP
1977 RLDT "CHIMERA"
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bob lico
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Post by bob lico »

1973 is the year of the change.let me tell you when you install a transducer you will be in for a surprise ,use a extra deep holesaw!!!!UNBELIVABLE-hull
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John Jackson
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Post by John Jackson »

I have a 1961, which is the first year. If the hull is any thicker than newer models, I couldn't tell although I never actually measured two cut-outs from two different boats. To tell the truth, the glass does not seem that thick to me at all. It is solid and well designed, which is what I think makes it seem so thick. I guess the only way to really settle the issue would be to keep some hole saw cut-outs from repowers and transducers and such from different boats and measure the thickness. Even this might be misleading unless the samples were on the same place on each boat. (From doing the work on my boat I could tell that the thickness varies considerably from place to place on the boat.) Even then, I think you would need to sample a lot of boats because the hand laid construction no doubt causes some variation from boat to boat. Maybe someone who worked at Bertram would know but it seems like there are a lot of "urban myths" about this boat.

I don't think it matters much because as JP notes none of them are known for hull failure.

On my boat I had to sand off all of the gelcoat to get rid of the gator skin. It was a big job. I read that this is from the gelcoat formula which continues to cure to this day which is culprit. Take a good look at the gelcoat of the boat you are buying for any signs of gator skin unless you have a lot of free time and really like sanding or unless you are fat of wallet.

As best as I can tell, my boat is about half a knot slower than all of the other boats that I know of with the exact same power and props. The lift strakes on my boat are significantly different than newer models, and I think that this is why.

With 454's and 1/1 trans my boat hit 34 knots on GPS with the tide once right after I tuned it up and was "testing" it. Now I have Cummins 270's and with the tide I once hit 30kts when I was seeing what she could do. Now it seems that my top end is somewhere between 28 and 29.5. At cruise at 2400 rpms I am somewhere between 24.5 and 26 and the load does not seem to matter as much as current. On average I'd say that the speed is usually between 25.5 and 26kts in a calm sea.
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Harry Babb
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Post by Harry Babb »

I have a 66 model Express. DeNada's hull is about 5/8" thick in the strut area and midship near the keel area its more like 3/4" thick and midship just above the chine I drilled and installed a thru hull...........at that point the hull was just under 1/2" thick. The stringers are glass covered wood. In the engine area the glass thickness over the wood stringer is about 3/8" thick

Just as JP stated all of my bulkheads were delaminated, the engines sister stringers are weak, the rudder shelves needed rebuilding but the hull itself is still strong.

Harry Babb
hb
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bob lico
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Post by bob lico »

harry 1/2" thick midship above the chine !! harry thats solid glass the new boats are less than that with cheap shit core some with balsawood.bang on the sides of a wellcraft ----the hole boat wabbles.i see a thousand boats a year you would go home and kiss your bertram after you see what on the market today.
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scot
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Post by scot »

5/8" thick in the strut area and midship near the keel area its more like 3/4"
Harry my 1969 B25 is about the same.

John,

I have the "gator" gelcoat as well but it appears to be mainly on the cap and the transom, hull sides look good....so I guess the solution is sand it down to the laminate and apply a fairing compound?? ouch.
Scot
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
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Harry Babb
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Post by Harry Babb »

Bob
I go to boatshows around here every year and do just as you stated....I bang on the sides with my fist and your right.......sounds like a big bass drum and wiggles a lot.

My last boat was a 72 Chapparel..........It was pretty stout also. Once a lot of years ago my son Chris and I were going across Mobile bay headed to the Gulf and I ran over a section of a pier that was floating loose out in the middle of the bay. It felt like that Chapparel went air born like the General Lee on the Dukes of Hazard. No damage to the hull........wish I could say the same about the outdrive and propeller

Scot..........every thing I build is usually big.......heavy.......bullet proof and nearly indestructable. I remember you saying something like that a while back...........These boats simply fit my way of thinking.

Harry Babb
hb
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Jareb
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Post by Jareb »

Thanks to everyone for their advice and insights. It sounds like a good survey of the boat is more important than the year of manufacture as to hull quality. I'm not ready to strip all the gelcoat so prefer to buy a boat in decent shape and update a solid hull. Thanks again- let the search begin
John
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John Jackson
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Post by John Jackson »

Scot,

A prior owner faired and painted over the gator skin and the cracks came through. I sanded mine down to the green my fiberglass guy rolled and sprayed high build Awlgrip primer and faired it out then painted with Awlgrip. I think that the only way to get rid of the cracking is to sand it all off.
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Bob H.
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Post by Bob H. »

Scot,

My 66 Bahia Mar had tiny stars in the paint, previous owner painted hull only, after media blasting entire hull the gator skinned gel coat had to be removed. It took over 40 hours of very careful grinding. The top cap is original gel coat and is fine, go figure. I then applied 8 coats of West System with additive to form a barrier coat. From here I plan to follow the Awlgrip prime and fair steps. The bulkheads were gone, steering shelf gone, have built all new bulkheads, steering shelf and re tabbed any questionable stringers. Start with a GOOD hull and go from there. Bh
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
Raybo Marine NY
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Post by Raybo Marine NY »

pay extra for a clean boat regardless if you are going to bring it down to the stringers, you will be MUCH better off in the long run.
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