Cross Member Sprung Up !

[macbeth]

I removed the fuel tank to have it cleaned out. The sailboat is a 1988 Niagara 31. I've owned it since 2000. I suspect the fuel tank has never before been removed.

AT ANY RATE, when I took the tank out, I found one of the cross members that the fuel tank sits on had sprung up out of the fibreglass. I stuck a 12" skewer into the gap and it ALL disappeared !

Q1: How serious is this ?

Q2: What needs to be done to repair the situation.

See photos attached.

Thanks

[David_Old_Jersey]

If it is just to support the fuel tank then not too serious (although the post at the end suggests that it might also be doing a bit more - supporting the cockpit?)

The fix? Angle Grinder (down to the hull) and replace entirely (given the state could possibly get away with using only a wire brush attachment or 2 on a drill - albeit slower). IMO will be easier (and better) than fannying around with fibreglass / epoxy to attempt a partial "fix" (Bodge?). Access likely to be a pig either way.

The only other thing I would say, is if the other bearers / cross members are also supporting the cockpit I would investigate them further - with a hammer and a drill (both with a drill bit and wire brush attachment) and patch the holes with epoxy / a filler. Any signs of wet or delam and you already know what will be happening next......

Not familiar with the specific boat - but if an Owners group would be worth getting in touch to see if anyone else already gone down the same road.

[macbeth]

Originally Posted by David_Old_Jersey

If it is just to support the fuel tank then not too serious (although the post at the end suggests that it might also be doing a bit more - supporting the cockpit?)

RESPONSE: The "post" you mention, is actually another piece of wood sitting on top of the "sprung" member and supports the cabin floor. i.e. the "sprung" member goes from Port to Starboard underneath the cabin floor. It's fine on the S'brd side. On closer examination this morning, I see it's actually two pieces of board stuck together. Hence the "split" along the top.

The fix? Angle Grinder (down to the hull) and replace entirely: RESPONSE: Very difficult to grind down. At it's thickest near the far end you can see, i.e. as it approaches the middle of the boat, it must be 4" thick. I think to remove it will require side cutting it and then maybe grinding the last part. Not sure this is viable. Might have to replace the whole member from Port to S'brd - a BIG job !

Access likely to be a pig either way. RESPONSE: Agreed ! Other points noted.

Thanks for your response.

[David_Old_Jersey]

Hopefully others will also chip in.........

Obviously hard to completely understand without being "hands on" - but if the wood underneath the board that has sprung is sound then could try just removing that and replacing (then glassing over). Still would require a lot of fiddling around in poor access - do you have access to a small child?! (nimble fingers and can fit in small places, plus they work cheap! - trust me, I once was that small child!).

Alternatively, a couple of six inch (err, measure carefully!) nails and a coat a paint. With fuel tank on top no one will ever know. Will probably see your ownership out. and then someone else can post about it on CF.........


....note the word "probably" .

[Geoduck]

If there is no rotten wood under it, just inject epoxy under it and clamp it back down - use a jack & some blocks. After it goes off, you might consider adding another layer of matt & cloth to beef it up. Make sure you get plenty off epoxy under the middle. You can get big syringes at a feed store/ vet supply - use a piece of 1/8" clear plastic pipe/hose to get it up under there and squirt away.
If you build it up, make sure you'll have clearance to get your tank back in!
Have fun!

[zeehag]

i would use screws instead of nails..just sayin...better longevity and security. rust factor also.

[enovillo]

I don't know what the best way to fix it, but I think it might be important to keep in mind that Niagaras have cored hulls.

[foolishsailor]

Judging by the color of the wood it looks like there is dry rot on the piece but only so far back. I would remove the end of the piece that is rotten, should be easy as it will be soft, to see what the condition of the wood is underneath. If it is fine then just cut back the top piece to clean wood and scarf in a new piece or just but joint a new piece and reglass in.

Make sure it is nice and dry before glassing.

If the wood underneath is damp then you have a more serious issue but still solvable.

[foolishsailor]

The question to ask as well is why/how did it pop loose? And when? And will it do so again once fixed? The dry rot likely happened after it sprung and was no longer protected and would not be the reason it is loose.

[rognvald]

Macbeth, The important consideration is what caused the problem: poor initial layup, water egress, structural failure, poor choice of wood. Before attempting any repair you need to diagnose why the failure happened and address that issue. Only then should you repair as needed. The pictures look as if there is considerable rot in the structural member as well as the surrounding area. To do a truly proper repair you must know the complete function of the piece (tank and/or cockpit support), as others have noted ,and then remove everything bad as well as cleaning the entire surrounding area and starting with clean raw fiberglass. Anything less than this will necessitate a revisit at a later time. Good luck and good sailing, Ron

[David_Old_Jersey]

Originally Posted by zeehag

i would use screws instead of nails..just sayin...better longevity and security. rust factor also.

Well, if you have money to burn by going all posh .

[macbeth]

I was recommended to talk to the local "expert". By lucky chance I found him. Seems competent and has good reputation.

He remarked that the manufacturer should have completely glassed over the wood. Instead they "sort of glassed" over the cross member. Over the years moisture has seeped underneath the member. Unfortunately, it freezes in the winter in Ontario, and this he thought had caused the member to spring. He thinks it is completely repairable. Wants to think about it and will contact me during the summer to give me an estimate and approach for the work. He said there was no reason why I shouldn't go sailing this summer. We agreed he would work on it at the end of the sailing summer.

Sounds good to me. I'll just not put the fuel tank in as permanently as I was going to.

Thanks for your responses.

[Noname]

Originally Posted by David_Old_Jersey

Well, if you have money to burn by going all posh .

Maybe silicone bronze screws, at that.

[David_Old_Jersey]

Originally Posted by Seaduction

Maybe silicone bronze screws, at that.

I had never thought of Zeehag with anything made of silicone before now...........

[rognvald]

Originally Posted by macbeth

I was recommended to talk to the local "expert". By lucky chance I found him. Seems competent and has good reputation.

He remarked that the manufacturer should have completely glassed over the wood. Instead they "sort of glassed" over the cross member. Over the years moisture has seeped underneath the member. Unfortunately, it freezes in the winter in Ontario, and this he thought had caused the member to spring. He thinks it is completely repairable. Wants to think about it and will contact me during the summer to give me an estimate and approach for the work. He said there was no reason why I shouldn't go sailing this summer. We agreed he would work on it at the end of the sailing summer.

Sounds good to me. I'll just not put the fuel tank in as permanently as I was going to.

Thanks for your responses.

Why not install a small flexible fuel tank that can be easily installed and strapped in securely until the repair is made? Are you willing to take the chance of further or extended damage to your boat if the hard tank dislodges under sail? Do you forsee a safety issue with reinstalling the old tank temporarily? I once met a guy named Murphy . . . Best, Ron