Contessa 26 Tech Notes

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Discussion on cored decks

Question: I recently read an article that said that Contessa 26s were built without a core in the deck. As I have recently acquired Tepukei (a 1988 JJ Taylor version) and have not yet had need to drill into it’s deck, I am unsure whether to believe this or not. Can anyone confirm or refute this? Frank Otta

Answers from the Groop:

1. It is true. Our little boats are built like tanks. no balsa or other things that soak up water and rot.. The only drawback is that in colder climates like the great lakes area in the fall and spring the boats do tend to sweat over night if they are shut tight while you are sleeping so ventilation is a must. Randy

2. The foredeck is cored with end grain balsa with a total composite thickness of about 1”. Weather decks are also cored with balsa of lesser thickness. Since I’ve had to drill thru these areas, it’s hard to miss it. Most of the coach roof is not cored but stiffened by the inner liner. As long as the core is dry and remains attached, this is a strong method of construction. Merrill

3. Could there have been a change somewhere along in the production???? Our 1976 does not have balsa in it, honest. I have made holes in the foredeck as well as the coach roof and no wood. Randy

4. Jeeezze, Randy, There could have been a change in ‘76. When replacing my foredeck mooring cleat, I was astonished at the thickness of the glasswork and the core. Most boats of this size would have cored the deck with 1/2” core material. I had only had two beers at the time and there was a core. Let’s hope that someone else pipes up. Merrill

5. It appears that J.J.Taylor & Sons seem to have experimented with a number of stiffeners. My 1974 Contessa was reinforced with 3/8” plywood (I have the core samples) but others of the same vintage were reinforced with end-grain balsa or a foam like material simply referred to as 4mm coremat. The layup schedule for a Contessa indicates that she is rather a substantial boat on deck: after the gel coat comes a 1.0oz chop strand, followed by 1.5 oz strand followed by 2.0oz woven roving the coremat and all flat surface reinforced with 3/8”core material (what ever was handy) and the finish layer is another 1.5oz strand mat. Peter ,”Blue Peter”

6. Hali Kai II’s hull was laid down in 1975 and finished in 1976. While installing two 6” bronze cleats on the fore deck, I found that the deck was cored with some kind of wood. Not wanting any problems with rotten deck core and delamination in the future, I did the following: Drill oversize (1/2”) holes where the new fitting will go. Tape under the exit of the hole. Fill the hole with thickened epoxy. Let set at least over night. Redrill with proper size bit for the bolt being used. Counter sink a slight bit (1/8”). Coat the bottom of the fitting with a caulking recommended for the job and spread out to a uniform thickness. Put a bit of chalk in the counter sink. Place the fitting over the holes and slip the bolts in. DO NOT TIGHTEN. Let the bolts bottom out but DO NOT TIGHTEN. Leave at least overnight so the chalk sets up and forms a gasket. Cut a backing plate out of 1/2” plywood or aluminum or stainless plate at least three times larger than the foot print of the fitting. Chalk around the area where the bolts emerge from the over head. Slip the backing plate on and use fender washers if using a wooden backing plate. Lock washers and nuts can be tightened now. Cap nuts may prevent a nasty gash but still leave a dent. It’s a lot of trouble but pretty much guarantees a leak-free deck. Tom Spitznagel, Hali Kai II, hull #153.

7. The boat is a 1981 J.J. Taylor and definately is cored with balsa throughout the deck. I mounted a vent and installed some deck hardware this summer. I had also read an article stating that Contessas were all solid glass. Imagine my surprise when I cut my first. Neil

8. Does anyone have any contact with someone who was involved in the JJ Taylor production run – or even some names I could try to track down, seeing how I’m in the Toronto area – we could run this by? This is a subject we’re obviously all pretty interested in, and for my ten cents worth, hard though it is to believe there may have been a point in production where coring was dropped totally in favour of a straight fibreglass structure, with deck reinforcement from the liner only, I have fairly good reason to suspect Randy may be right; certainly as far as the foredeck is concerned, and possibly re. the side decks also. There’s also one magazine article or book reference I’ve read – sorry guys, can’t remember where now, but within the last couple years; I’ve looked but I can’t find it again – that stated there was no coring anywhere in the deck structure (‘tho everything else I’ve seen printed has stated there is). My suspicion is there were variations across the run as a result of manufacture cost factors – or even short term material shortages – at given times, rather than any deliberate attempts to mod. the design (tho’ I’m not ruling the latter totally out); so it could turn out everyone’s right, and it just depends on the particular boat. Be real nice to narrow any changes down to specific periods or hull number sequences tho’... Robin

9. I thought I would add my 2 cents worth and as I think that I have the oldest Contessa in the Groop (I stand to be corrected) a 1970 it might add to what we know about the early models . This spring I drilled a 3/4 inch hole in the deck, just forward of the mast to run a radar cable through, and it was definitely cored, looked like about 3/8 inch plywood, and although I have not yet drilled any holes in the foredeck I am sure that it is cored as I have a small spot on the starboard side that snaps occasionally when walked on, a sure sign of a cored deck that is a little bit sick(a project for someday). I hope this helps with the discussion. Kent Ross

10. God what did I start. It seems we may all be correct. Interesting though. It sort of makes each of our boats one-of-a-kind. Randy