deck construction of the Bristol 40

[gdki...@gmail.com]

Hello Everyone!  Can you supply information about how the decks were handled on the B40?  I am seriously considering buying Gem up in Maine; she has a teak overlay, and the question is, what the devil is under it? Was the teak applied directly over the completed standard deck, that is, substrate/core (plywood? balsa?), with standard fiberglass surface, and then the teak over that? Or the teak directly over the substrate? What are the thicknesses of the layers? Also: the hull to deck joint: I assume there is a flange with the deck bolted on top; how wide is the flange? Wide enough to accommodate the stanchion bolts? Thanks, from David Kiremidjian

[crew4...@comcast.net]

Hello David,

My boat, hull No. 28, built in 1968, has an end grain balsa cored deck and cabin top.  I don't recall the balsa thickness.  When we bought her, about 60% of the balsa core was rotten, having been soaked for who knows how long.  I had worked in a glass boat factory briefly and knew how to repair it but also knew that I did not have the skill level to do it right.  It is a 3-P job, picky, picky, picky.  I hired a very good  yard to do it for me. We elected to grind the top glass off, excavate the balsa, replace the balsa and then re-glass, all from the outside.  It can be done because the various layups are stout enough to permit stripping the layers off without unduly weakening the whole structure. 

This approach necessitated painting the deck, so the hull was painted, too (Awlgrip).  My wife and I stripped all the hardware and gear off the boat so the experts could do their work, after which we put it all back together.  This cost more than $50,000.00 all in all down, paying my wife a dime an hour and myself a nickel.  We have a beautiful boat for all that work, but it wasn't easy or cheap.  

You can see the hull-deck joint very clearly in the cockpit lockers, where you can measure layup thickness and flange width.  On my boat the shape and dimensions change very little from the bow to the transom.   Some of the stanchion bolts land in the flange, some only in the deck.  We have had most of the interior out to repair, refurbish, replace, etc.

All this says nothing about teak overlay.  I've never seen a B-39 with a teak deck.  There are several possible layups.  If the teak was laid on top of the same basic deck construction as ours, and if screws were used to lay the teak, my fear is that each of those scores of screw holes is a source of water intrusion into the balsa core.  My facetious belief is that no one is as good as I am at bedding screws in my boat, and I'm not really good enough, in all truth.  It is a damn hard job with zillions of variables.   The presence of the teak also complicates the measurement of moisture content in the core.  You should try to retain god's own surveyor.

If you have questions, shoot. 

Jim Handley

"Sophie" a yawl

---

From: gdki...@gmail.com
To: "Bristol39-40" <bristo...@googlegroups.com>
Sent: Friday, April 15, 2016 11:23:36 AM
Subject: [Bristol39-40] deck construction of the Bristol 40

Hello Everyone!  Can you supply information about how the decks were handled on the B40?  I am seriously considering buying Gem up in Maine; she has a teak overlay, and the question is, what the devil is under it? Was the teak applied directly over the completed standard deck, that is, substrate/core (plywood? balsa?), with standard fiberglass surface, and then the teak over that? Or the teak directly over the substrate? What are the thicknesses of the layers? Also: the hull to deck joint: I assume there is a flange with the deck bolted on top; how wide is the flange? Wide enough to accommodate the stanchion bolts? Thanks, from David Kiremidjian

--
You received this message because you are subscribed to the Google Groups "Bristol39-40" group.
To unsubscribe from this group and stop receiving emails from it, send an email to bristol39-40...@googlegroups.com.
To post to this group, send email to bristo...@googlegroups.com.
Visit this group at https://groups.google.com/group/bristol39-40.
For more options, visit https://groups.google.com/d/optout.

[garabed kiremidjian]

Hello Jim,

Many thanks for this generous and detailed account of your work with your boat.  I was involved in the exact same process a few years back on the rotted deck of a C&C Corvette. It is useful to know that the bottom layer of glass is thick enough to shovel up the balsa without the hull caving in.  Do you have any recollection how thick the bottom and top layers were?  I think that the teak overlay probably went over the standard deck, simply screwed down, but this really would not have held at all with a balsa core, so they must have substituted a plywood core for the balsa.  Bristol was, after all, a conscientious builder.  That doesn’t change the fact that each of the fasteners became an open conduit for gallons of water, as you point out.  The other question is what bedding compound was used beneath the teak; given the vintage of the boats, it was probably thiokol.

So if you can remember the thicknesses in the layup, let me know. Tim Fuhrmann reports that the whole standard laminate on  his boat is 2-1/4” thick which is a bit hard too believe.  Were it only so, one wouldn’t care how rotted it might be!

Best,

David

You received this message because you are subscribed to a topic in the Google Groups "Bristol39-40" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/bristol39-40/Q7pdJc_Pcvo/unsubscribe.
To unsubscribe from this group and all its topics, send an email to bristol39-40...@googlegroups.com.

[James Lamb]

David,

I suspect that the deck was laid directly on the original fiberglass deck.  My boat is number 25.  I have seen a number of 39/40s, but never one with a teak deck.  It might have been installed after the boat was made.  I wonder how high Gem’s toerail is?  My toerail is 2 1/4” above the deck (not counting the thickness of the genoa track).  If Gems is shorter, it could point to installation after manufacture.  

I had no water in my deck (one of the few things I did not have).  Jim’s is correct, you may have trouble determining that the core is dry with a teak deck on top.  I am not sure if you can measure reliably the water content in the deck from inside the cabin.  My boat has a fiberglass liner that would make it impossible.  Each screw gives the water a potential way into the deck core.  

I replaced my toerail several years ago.  The toerail covers the flange and hull/deck joint.  It was filled originally with 5200 that did not hold up well after 30 or 40 years.  It leaked so badly that the previous owner installed a gutter system to move water to the bilge.  I took the system out and sealed it with epoxy resin while the old rail was off.  No leaks in 4 years.   Most of my stanchions are secured through the deck only, inside the toerail, with backing plates.  It is quite secure.  Every screw hole was opened up, filled with epoxy, then redrilled to prevent water intrusion.  

Jim Lamb, Ondine  B-39 #25

On Apr 15, 2016, at 4:54 PM, crew4...@comcast.net wrote:

[James Lamb]

I think Tim is right about the thickness of the deck.  I cut out a 30x30 piece and installed a hatch in the cabin.  I could not believe how thick and heavy it was!  The cabin top was a couple of inches thick.  

Jim

[garabed kiremidjian]

Hello Jim,

Thanks for your observations, especially that the teak may not be original, although from what I can gather from the photos, it does indeed seem to be.  Something to be verified.  The height of the toerail over the deck will also be a useful bit of information.  More so, in any case,  is your confirmation of Tim’s estimate of the deck thickness.  A structure like that would remain reassuringly strong, even with deterioration. I’m doing a bit of rationalizing here - - -

Best wishes,

David

[crew4...@comcast.net]

Hi again,

I have no notes or memory about layup thicknesses.  The only place I can access a cross-section is the hawse hole for the windlass, but that would only yield total thickness in a stronger-than-typical location in the middle of the foredeck.  Everywhere else involves not only deck layups, but also the interior liner and the gap (variable) between deck and liner.  If you want that, I'll get it.

Jim

---

From: "garabed kiremidjian" <gdki...@gmail.com>
To: bristo...@googlegroups.com
Sent: Friday, April 15, 2016 2:57:55 PM
Subject: Re: [Bristol39-40] deck construction of the Bristol 40

[Matthew Thomson]

I happen to have the main deck and cabin top open on my 1969 Bristol 39 presently. B39 and 40 are the same boat, except for the interior layout changed. I did not have a teak deck, just the patterned embossed non-skid. The coring is 3/8" end grain balsa on the cabin top and the main deck, as well as the cockpit sole. I replaced my balsa coring with closed cell foam as it was wet in the area's they always get wet (under the Edson, around the fuel fill connection, around the old canister bilge pump deck access plate, Stbd. Chain-plates and forward outboard port of the main cabin slider). Only way it's 2 1/2' thick is if you include the cabin liner, and the gap between the liner and the cabin top/deck. The layup on the top skin is about 3/16" to 1/4", and the lower skin is maybe 1/8". Layers of mat and cloth, no woven in the deck.  All together maybe 3/4" thick. The teak deck would be installed on top of the "factory" deck, not sure if its bonded or screwed. Would depend who did it and when. I would assume it was screwed down, in which case you may have some wet coring if the screws leaked. I doubt it was anything but balsa as the boats were "semi-custom" in that the hulls and decks were all built the same and then "finished" as spec'd by the customer. Also knowing Clinton Pearson personally, he would not have spent the money or time to try and laminate with wood, I'll send him and e-mail and ask him. Last time I talked with him he was talking about how cheap that stuff was and getting truckloads of Balsa and Teak delivered to the factory. I had area's where the balsa was rotted away, but the 1/4" top skin would still hold a screw. The combo of the balsa and the 2 skins was very strong. I am using 2-4 pry-bars (wonder bars) to pry the skin away from the core even where its wet. 

I was surprised when I found out that the deck flange went all the way 4-5" inboard of the toe-rail on the main deck at the chain-plates. So there is no coring in that area adjacent to the toe-rail, it's solid layup. I moisture surveyed the deck and the flange registered as wet all the way around.  I finally figured I was picking up the hull joint and toe-rail fasteners. The main deck also goes solid again at approx. 2" outboard from the cabin-top where it turns up from the deck. The cabin top sides are solid un-cored. and then it turns inboard on the cabin top and becomes cored again. The coring was ground to a taper at the outboard edges to make it an easier transition to laminate over. 

I cut the top skin off to chisel out the wet coring, cut a piece of new core based on the top skin I cut out, and bonded the new core, followed by the old top-skin all back in one shot. After that cured I then I beveled where the cut was made on the top skin and re-laminated the seams. Saves allot of time and money, and keeps the deck looking smooth. Once you start to do it you can be pretty proficient at it. It's work, dirty, dusty, itchy work, but the stout construction of the deck makes it easier. Big deal is getting a good survey to find the moisture. I bought my own moisture meter and sounding hammer. I also learned to apply common sense, areas get wet only where there is a fastener or seam that can and has leaked. I also used some drill holes to sample the coring to see if it was wet or dry, they are easy to fill. I used a forstner bit so the shavings would be extracted nice enough to inspect.

My worst area, that I wasn't expecting, was from area under the hood for the main cabin slider, I had to replace 5-6 sqft around that area because the seam under the slider hood was leaking. I also have some evidence that their was some leakage inside the P&S Dorades, however it wasn't bad enough to replace, and my plan is to pour penetrating epoxy in the dorades to fill those seems and anywhere that may have leaked around them. On the main deck only place I had a problem was the at 2 forward STBD Chainplates and about 5 sqft aft and inboard.

Gem is a pretty boat, she has been for sale a couple times in the last 5 years, If she wasn't priced so high when I was looking back in 2011 I would have looked at her myself. Back then she was over priced and she sat on Yachtworld for almost 2 years and I watched as the list price dropped from $60K down to $40-something-K. Then I recently saw her posted for $32.5K. I was wondering why she wasn't selling and wondered if the teak decks may have been an issue. If you can do the work I think she's a good boat. I would do it in manageable sections instead of all at once. I'm not sure the lower skin alone would be strong enough to support the cabin top and keep the hull shape.

If you have any other questions, don't hesitate to ask. V/R Matt (BLUEMOON, 1969 B39 CB Yawl)

[garabed kiremidjian]

Hello Matthew,

Much thanks for this greatly detailed account of the decks and other spots where experience shows the laminate vulnerable.  Especially for the precise description of the layup.  It does accord with what one would expect, but other posts on this matter affirm that the coachroof (for example) is 2” thick.  If you would communicate with Clinton Pearson and ask him about such details, it would clarify things immensely.  You are probably correct in saying that any teak overlay would have been screwed into the basic deck with the fasteners holding on for dear life to the 1/4” top layer of glass.  But these would eventually let go, and this is what I fear has happened with Gem.  In any event, do inquire of Pearson if plywood was ever substituted for the balsa core for the teak decks (you’re doubtless right that he would not have swallowed the expense) just to put the matter to rest. Doesn’t change the fact that there’s lots of wetness in there.

Another question: what problems have come up with centerboard, centerboard pin, pennant, etc.?

Lots of very useful information coming in on this.  Thanks again.

David K.

[Dan]

I can't imagine the deck being 2 inches thick. If it was I would think it was a major screw up by the factory people and also if they did lay it up that thick I would think they would have had problems fitting in the molded headliner. Until someone shows you a picture I would hold off on believing the 2 inch thick report. Yes, very possible but it would serve no purpose having it that thick.

I have several core samples from my deck and the skin on the cabin top was 1/4 inch thick followed by 3/8 core and then the bottom skin was 5/16 inch thick. Total is about 1" thick. A core sample from the aft deck had a top skin of 3/16 inch followed by 1/2 inch balsa and with a bottom skin of 3/16" plus. Again about 1 inch thick. It's a pretty serious layup and even with a rotted core I would not worry about a structural failure. It would feel spongy but you ain't busting thru. 

I would assume the core is badly rotted under the teak decks on Gem. If you do it your self it's a massive job that will take many hundred of hours to totally overhaul the deck and Awlgrip it. Having it done professionally makes no Economic sense. I would keep looking for a boat in better shape and certainly one without teak decks screwed on. Glued maybe, but definitely not screwed on.

Dan Stadtlander

Mirari

Bristol 39, hull #43

Sent from my iPad

[garabed kiremidjian]

Hello Dan,

The precision of experience.  Thanks, very useful.  Great data accumulating in this thread about decks!  What you describe here is what one might logically expect to have been the practice for a boat of this type. Yet there is a report of a piece cut from the coachroof for a hatch that was indeed 2” thick.  The signal issue is whether the rotting of the core is extensive enough to be of immediate concern.  Were it a wood boat in question (where most of my experience is) one replaces everything that is  suspect.  With a standard glass and core sandwich, there is perhaps more buffering of the weaknesses.  And I know it is a devil of a job, having taken part in a total re-coring of  the deck of a 31’  C&C Corvette a few years back. Depends on how great one’s tolerance for possible failure is. One can easily go completely crazy addressing this sort of stuff with a nothing-less-than-back-to-original philosophy. Your warning about screw-fastened teak overlays is the obvious caveat about the whole situation.

Best,

David

[Maurice Lyerly]

Guys,

For what it's worth,  Bristol offered teak decks as an option in the late 1970's. 

I've attached the factory brochure that shows the very dark teak decks.

I've also attached the Boat Show Package Sales sheet by the then dealer, Atlantic Sailing Yachts.  You'll see in the right hand column, 4th entry down the item, "Teak Decks" as part of the package.

I think this is a late 1970's...there is no date on the Sales Sheet. However,  do have one from 1981 or so that indicates a Boat Show price without teak decks of $87,790.

The Teak Deck sales flyer has a show price of (read it and weep) $58,900.  I seem to remember the dramatic spike in prices as a result of the Arab oil embargo and the price of oil rocketing skyward.

It was a long time ago but I am fairly confident I looked at a 40 at the Boat Show in Annapolis that had teak decks.

I've been collecting and hanging onto this stuff for years.

Maurice

Bacchus

[Matt (BLUEMOON)]

From Clinton:

I do not recall ever installing teak on a Bristol 40 deck, but if we did, I would assume we used exterior plywood with exterior glue and a solid core. However 1976 was a year when we had just returned from time in India. I would suggest that he ask a surveyor to sound the deck, and if it seems OK it is probably alright for a further number of years.

Best,

Clint

[garabed kiremidjian]

Clinton Pearson’s information via Matt adds to the very interesting richness of our inquiry.  So to speak.  He does not recall having installed a teak deck on a B40, but we also have the brochure from the 70s offering teak decks as an option. It would be great if we could canvass all the other owners who have opened up a deck  or coachroof and gotten a good look at what made up the sandwich. 

[Jack]

Hi, Did you buy Gem? Nice boat. Was on her looking at mast step as my 1982 B40 needed some work on the step. I have a B40 yawl in Portsmouth, NH. Let me know if you have any questions about these boats. John

On Friday, April 15, 2016 at 2:23:37 PM UTC-4, gdki...@gmail.com wrote:

[garabed kiremidjian]

Hi John,

No, I did not buy Gem.  I waffled around and then heard the boat was sold.  Probably went quite cheap.  There were too many things I had misgivings about so I do not regret missing out. I met a man down here who was in RI during the time these boats were being built and got some great input.  The men were all highly skilled Portuguese boatbuilders, who did much ad hoc, so the quality from boat to boat was quite inconsistent.  The boats whose owners were stopping by every once in a while during construction turned out the best, evidently. As you know, various reports I received from current owners on specific characteristics showed wide differences; thus the reason.  

If you know any B 39-40 for sale or partnership, let me now.

Best,

David K.

[paul....@fairworkplace.net]

Hi David:  My Bristol 40 Calypso, Hull 76, 1979, is on the market if you are interested.  She is a full keel yawl, 56 hp turbo Yanmar 1991 with some 2400 or so hours, in good shape; new main and genoa (155%) about 2008 or so, spinnaker and gear, and a good many other sails, Flag blue Awlgrip 2006 or so, new Espar cabin heater last year, rubrails, a good many other features inc. Raymarine radar, Standard chart plotter, ground tackle, new shaft couple years ago, etc.   Please don't hold me to these dates as I haven't checked them, but I believe they are pretty good approximately.  Some things need attention: new cockpit cushions probably,  some work on dodger.  Has cruised successfully to Maine every summer since we got her in 2004.  Glad to discuss if you like, and I can get you pictures and more detail. 

 

Best, Paul Merry,   Calypso  1979 B40 Hull 76 

You received this message because you are subscribed to the Google Groups "Bristol39-40" group.

To unsubscribe from this group and stop receiving emails from it, send an email to bristol39-40...@googlegroups.com.

[Maurice Lyerly]

Paul,

On a different note, what did you think of the Espar heater?  Were you satisfied with it...would you do it again?  Where were the vents placed?  Professionally installed?

Thanks,

Maurice

On Thu, Jun 9, 2016 at 4:44 PM, Hinckley Dan <d...@suiattle.org> wrote:

I wonder what he’s asking…

Yes, we likely should.

¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬
Dan Hinckley         ⎈
d...@suiattle.org

[garabed kiremidjian]

Hello Paul,

What is the asking price Calypso?

David