Strengthening Boat

[Freerider]

I'm doing some structural work on my boat when I have it on the hard. I'm thinking of adding some extra stringers to stiffen the hull, is it worth the effort? Where would be the best place to add them?

What about stiffening the deck by running stingers perpendicular to the hull? Would it be worth the effort, even if I had to cut and repair the liner?

I'll be doing some bluewater with the boat, but not the southern ocean or anything.

The boat seems pretty solid and I know other stock Hughes 35's have crossed oceans but, now is the time to do structural work if needed.

[paulk]

What makes you think the hull needs stiffening? Is there oilcanning or are there flex stress cracks? Reinforcing in the way of these things may stop them from getting worse. Adding stringers will probably stiffen the hull, and may be worth the effort if the hull isn't strong (see: oilcanning/flex cracking) enough to begin with. Getting in to the inside to reinforce those specific places may mean ripping out all the interior furniture and bulkheads, however, and these also play a role in stiffening the hull. You may be on the hard for a lot longer than you anticipated. Adding new beams to the deck or cabintop may strengthen them too, but if the problem is a rotten deck core, new beams (and the attendant drop in headroom) are not the way to fix it. You may want to contact Hughes, if they're still around, or Sparkman & Stevens (they are!) to find out what they suggest before you go wild with a sawzall and more fiberglass.

[Freerider]

Well to be honest I'm not sure that the hull needs to be stiffened at all, but I just figured what's the harm in adding a few stringers since I have some of the interior ripped out.

You may be right though, I might just end up taking more time on the hard than needed.

[bwindrope]

Freerider, I echo the comment of paulk questioning the need for the stiffening. My primary thought would be to do some epic research into the boat and read other experiences. I would also see if it was possible to contact the builder/architect as they might have knowledge about any weaknesses that happened over time.

Casey has good descriptions of how to do the stiffening with stringers, and that is probably the easy part. My view on the pros/cons of adding stringers simply for the sake of extra stiffening is that stringers in the necessary places may be A. Hard to reach B. Take up storage space better used for something else and C. Take time away from other projects you are better off doing!

On this last point, I believe every one of us, no matter how diligent, recognizes that there is an endless list of projects we could be tackling. For out of the water projects, what about a super clean and treated prop? Does your hull need a good polish? Others like removing and rebedding all deck hardware comes to mind. Checking all mast fittings for corrosion. Removing and rebedding all windows. So many things that need doing so regularly and yet we all lack sufficient time to do them when we would like. So I guess I am asking about the opportunity cost of doing this project versus others.

Maybe, after all things considered, you just wanna do it because you wanna do it, and the damn boat is yours to do with what you want and you'd like the fiberglass practice. Well then...

Have fun!

[dabnis]

Free,

I am not familiar with your boat, however it is likely that a production
boat had a fair amount design work put into it so that it doesn't fail
on down the line. Modifying that design may transfer stress to other
parts of the hull? I would be really cautious about changing the basic
hull design unless you are having visual evidence that the hull is in
danger. Perhaps getting some input from a surveyor or a design company
might be helpful before hand.

Dabnis

[tommays]

For example on a 35' boat i sail on a naval architect did the new keel and the needed beefing up to support it BUT it still failed in a different and unexpected place two feet behind the keel when a rock was hit

[cruisingdream]

some things are ment to flex so they don't break

[Freerider]

So I contacted S&S about the design of the boat and Bruce Johnson told me that even though Hughes built the boat, S&S basically told them how to build it.

Who am I, to mess with it?