Flex in the hull normal for a 50+ year old boat

[PassingWind]

I recently acquired a '66 DS1 and started to clean her up. After removing the 2 boards that provide support between the seats and the CB I noticed that ther was some flex along the centerline of the hole. the CB housing has some flex left and right and you can see some flex in the centerline of the boat. not a lot but you can see it. It does have 2 stringers that were glassed in(not sure if that was factory or aftermarket...)

A little background on the boat, it was trailered its whole life and sat outside uncovered alot... It was always pitched to drain but never the less it was exposed to the elements.

Being that this boat is 50 years old is this not uncommon? whats the best way to remedy this flex? adding more glass? i have begun sanding the interior and want to start reinforcing if that the route I need to go...

I have a pic that I will post shortly to highlight the area of flex

Any guidance would be apprecaited

Also a second issue was that the rea 15 inches or so of bumper(along with the fiberglass tabs were removed for some reason and was seperating so I glassed that in and its fine. I am curious if I wanted to remove the rest of the bumper and tabs would glassing the deck and hull from the inside be secure enough? the shrouds are connected to the hull not the deck. the jibstay is connected tto the deck but looks like there is plenty of glass on the interior where the deck meets the hull at the bow.

I am able to launch my DS from my yard so It was always be put back on the trailer or anchored offshore.. Bumpers are not needed. I find it would look more sleek with the bumpers on....

Thanks all


Rob

[PassingWind]

Also the deck appears to have a little flex as well when you stand on the cabin to step the mast....

[GreenLake]

Check D&R Marine. Last I checked they sold the rubrail material (outer, rubber-like stuff and inner PVC guides). You should be able to replace yours entirely and it would make the boat look better. (There are end caps that mount at the transom, check pictures of other boats. If yours are missing you'd have to find a way to replace them).

I'll take up each of the other detailed subjects in a separate post.

[GreenLake]

Your hull deck joint does not require glassing unless it shows signs of failure. That said, you might want to glass the joint in the very front of the boat, the area that would get slammed when you sail the DS into chop.

[GreenLake]

The fore stay is attached to a deck fitting which internally is attache to a metal L-bracket which is embedded (more or less securely) into the fiberglass of the front of the bow (aka. the stem).

Some people have taken the precaution of drilling through the stem and through bolting the L-bracket. (Look for older posts on "stemhead" in this forum).

[PassingWind]

Check D&R Marine. Last I checked they sold the rubrail material (outer, rubber-like stuff and inner PVC guides). You should be able to replace yours entirely and it would make the boat look better. (There are end caps that mount at the transom, check pictures of other boats. If yours are missing you'd have to find a way to replace them).

Your hull deck joint does not require glassing unless it shows signs of failure. That said, you might want to glass the joint in the very front of the boat, the area that would get slammed when you sail the DS into chop.

Actually what I wanted to do was remove the bumper and fiberglass tabs completely.. Glass from the inside to strengthen the bond between the hull and deck.
The DS will not be on a dock it will be launched via a trailer from the my property. It would be moored if left in the water.

[GreenLake]

A bit of flex of the deck is fine, my '63 flexes when I step on the forward deck. The way to fix that is to add a deck stiffener.

Get a pool noodle. Slice in half - lengthwise. Get a large freezer bag, some fiberglass mat, fiberglass cloth and laminating epoxy.

Lay up 3 layers alternating on the freezer bag (you can cut it open - to get a longer strip - there's another technique that works "inside the bag" but I think it's overkill).

Stick your pool noodle underneath the deck with anything that works, from double sided tape to Marine Goop. (This step is temporary).

Then cover the noodle and one to two inches on either side with your laminate. Support as needed (sponges on a stick against the plastic, or it might be enough to just tape the edges of the plastic to the deck).

When cured, remove plastic. Leave front//back of the U shaped stiffener open, and you'll never have trapped moisture. Paint the epoxy, even under the deck there could be UV damage over time.

[GreenLake]

A full cure for hull flex would be to add a foam core. K.C. Walker has done that and written it up. Look for the "core project". While it takes work, it should make your boat "better than new" because it would be stiffer than when it came out of the factory.

Alternatively, you could simply add to the existing stringers and/or add small stiffeners in various areas. (E.g. CB trunk walls).

Stiffeners get stronger the thicker they are (distance between top and bottom layer). However, there's a natural limit on that. Alternatively, you could make them wider, or place additional ones in various areas.

For the existing ones you might check whether they have wood as core and whether that wood is waterlogged. Simply for that reason you might benefit from replacing them (using a proper foam strip as core material) and in the process perhaps changing their dimensions a bit.

The verdict on these boats is that they are generally "eminently repairable", however, if you don't at all enjoy this kind of work for it's own sake then you might be better off looking for a more preserved specimen.

[GreenLake]

OK, so far a few "off the top" answers from me. Just my perspective. Others may have additional input.

[GreenLake]

Actually what I wanted to do was remove the bumper and fiberglass tabs completely.. Glass from the inside to strengthen the bond between the hull and deck.
The DS will not be on a dock it will be launched via a trailer from the my property. It would be moored if left in the water.

Sure, you could do that - however, it could render your DS not "class - legal" because it changes the outer dimensions of the hull. That matters only if you intend to join others in races under class rules, or, if you ever contemplate selling it to someone who does.

As long as your ramp doesn't have a dock, and as long as you don't race (both from rules perspective and from the chance of getting too close to another boat) I see no reason why you couldn't be happy with a rail-free DS.

In that case, glassing the joint is a suitable precaution against possible loss of strength - check the part you are intending to cut off and see whether it contains a significant "lip" for the joint. I think it does. In that case, make your inside glass substantial enough to provide the same strength. (Also, goes without saying, you want to be really good in preparing the surface - remove paint, degrease, roughen).

[PassingWind]

Actually what I wanted to do was remove the bumper and fiberglass tabs completely.. Glass from the inside to strengthen the bond between the hull and deck.
The DS will not be on a dock it will be launched via a trailer from the my property. It would be moored if left in the water.

Sure, you could do that - however, it could render your DS not "class - legal" because it changes the outer dimensions of the hull. That matters only if you intend to join others in races under class rules, or, if you ever contemplate selling it to someone who does.

As long as your ramp doesn't have a dock, and as long as you don't race (both from rules perspective and from the chance of getting too close to another boat) I see no reason why you couldn't be happy with a rail-free DS.

In that case, glassing the joint is a suitable precaution against possible loss of strength - check the part you are intending to cut off and see whether it contains a significant "lip" for the joint. I think it does. In that case, make your inside glass substantial enough to provide the same strength. (Also, goes without saying, you want to be really good in preparing the surface - remove paint, degrease, roughen).

Good point about the class legal issue. I dont intend to race but if I ever decide to sell dont want to limit my buyers.....

As for as the noodle info above, I am planning on removing the 2 wood stringers installed now and redoing them.... Is the noodle to big to use on the floor of the hull? is there something else btter for the floor?

[GreenLake]

As for as the noodle info above, I am planning on removing the 2 wood stringers installed now and redoing them.... Is the noodle to big to use on the floor of the hull? is there something else better for the floor?

Get one of the structural foams. I forgot what K.C. used, look it up in his post. Names are something like Corecell or Dinycell...

On the floor, going higher than about 1" is going to be changing your boat. If you have the wooden floor-boards and intend to use them. make sure you can make them fit, if not, make sure whatever you do will allow you to walk on the floor.

Does your hull flex forward of the CB trunk? If flex there isn't significant you might do a "partial" core. Fill the space between the seats and taper towards the front - with some transition so water doesn't puddle in odd spaces.

K.C. might chime in with more expertise and his perspective.

[jpclowes]

I recently acquired a '66 DS1 and started to clean her up. After removing the 2 boards that provide support between the seats and the CB I noticed that ther was some flex along the centerline of the hole. the CB housing has some flex left and right and you can see some flex in the centerline of the boat. not a lot but you can see it. It does have 2 stringers that were glassed in(not sure if that was factory or aftermarket...)

Did you replace the thwarts between the seats and the CB trunk? They are absolutely necessary for the structure of the boat, and required by class rules. Without those the CB could fail.

[PassingWind]

I recently acquired a '66 DS1 and started to clean her up. After removing the 2 boards that provide support between the seats and the CB I noticed that ther was some flex along the centerline of the hole. the CB housing has some flex left and right and you can see some flex in the centerline of the boat. not a lot but you can see it. It does have 2 stringers that were glassed in(not sure if that was factory or aftermarket...)

Did you replace the thwarts between the seats and the CB trunk? They are absolutely necessary for the structure of the boat, and required by class rules. Without those the CB could fail.

I took them out to sand the hull. They will be replaced before the ds1 gets wet

[K.C. Walker]

Just because of the way these boats are made, i.e. one layer (no core) and pretty flat and unreinforced, trailering them knocks the original stiffness out of them pretty quick, I would think. As they soften up they become less responsive, however, in most cases it's probably not a critical issue. For racing or for higher performance sailing it is an issue but for just casual messing about, the boat will go decades longer with proper maintenance.

I was interested in higher performance for my boat, so I went for the ultimate stiffness of putting in a core. For me, it transformed the boat from one that I liked OK to one that I really like. The hull design is nice as a planing boat and I continue to upgrade it and feel like with the hull good and stiff, I have a good foundation to build on. I sailed my boat for a season before I started upgrading. I would suggest that you might want to do the same thing and find out whether you like the boat enough to sink time and energy into the overhaul and upgrades.