Cracked Stringers

[Happi1fla]

Finally getting back to it , Thanks Alex , and everyone
on sharing your pic's and info, Was able to get the
tank holder out, surprisingly easy by prying up with a 2 X 4

But Surprisingly I've got big problems , A crack in two
locations.
1st up front where the stringers start/ near the anchor locker theirs an inspection hole that was once cut, it has
a lengthy gouge on the outside of the boat also.
2nd crack is just into/below the tank holder a foot or so.

Question with these cracks , Is their a correct way to get
to the bottom of each stringer, (any pic's) Maybe removing
the top skin, and digging out the foam,

also any suggestions on toughening up what is cracked, material use, epoxy, poly resin any compound,
will go the long way around to fix this if I have too.

stressed , Thanks everyone.

John


[image]ttp://i215.photobucket.com/albums/cc314/Happi1fla/leftsideundertankholderslip.jpg[/image]

[Happi1fla]

Just adding a few missing pic's ,

Please help

Thank you , John

[GradySailfish]

Ok...I see whats going on. You can glass those cracks from the outside...simply grind away and then add a 3 layers of 1808/1708 over the area that is cracked. I didn't have those cracks in the stringers, but I did do some damage to them as I removed the deck, and thats how I fixed them.

I'm also willing to bet, the foam in those stringers is waterlogged and warrents removal and re-foaming. Check that out and make sure. Otherwise it looksl iike your project is looking good.

[JohnB]

What your looking at is not uncommon, they didn't get enough glass into the corners/edges of the stringers. Actually, I have seen worse (yes in seacrafts).
What I did with mine was, grind the surfaces to get some clean glass, fill the cracks with thickened epoxys, put 3 layers of 6" biaxel tape on it biaxel and use epoxy to put it all back together. Make sure you offset the layers, so you don't create a "hard spot". It will be stronger than when it was made. I would suggest doing this the entire length of the stringer.

I am not sure how much strength the foam in those stringers has. When they made these boats, I don't think they were using the high strength foam that is available today. I believe the box of fiberglass around them is where the strength is in these old boats. In most of them, the stringer glass is no longer bonded to the foam. You could drill small holes every 12" and "pour" epoxy down the sides if you really wanted to go nuts with it.

[EBEACH]

The first picture of your second post looks like the remains of something that was tabbed to the stringer and not the stringer itself. Its hard to tell, but looks to be the tabbing in of an old fuel tank support deck.

[Happi1fla]

Great information, will fill the corners/edges, and glass the entire length.
Still not certain on where to remove the glass to get inside where the foam is.
I could remove foam ,drill holes and epoxy as suggested, or could their be a thinner piece of glass that covers over the top, ( like the top to a wooden stringer,) where I could cut the top off remove old foam, glass over and refill with foam.
Would like to inspect inside where the glass comes up from the floor to see any internal cracks.
I guess what I ‘m asking are these stringers one solid box, where by cutting into the top would weaken them structurally, will plan on replacing all foam at some point
Just haven’t opened up that area yet,
I hope I’m making sense, just not enough sleep.
.

[JohnB]

I would not use glass, I would use epoxy. Lighter, stronger, and you get both a physical bond, and a secondary bond. If your looking at buying supplies or especially competant materials tech support go to bateau/boat builder central. They know what they are talking about and you can talk to them on the phone.

I would take a piece of wood, or even your foot, and press against the side of the stringer to see if the stringer skin has separated from the stringer foam by pushing in on it. If it is still connected, you won't get much flex in. Then I would drill small 1/8" hole down near the bottom of the stringer, especally near the stern, and see if water comes out. If it is real wet, I would plan on cutting the top of the stringer box, and digging out the wet foam, and replacing the foam. You can't believe how heavy those stringers become when they are wet. If it is dry, but loose, I would go with the epoxy every 12" the length of the stringer approach. It will reattach, and add a little strength. If it is a little wet, you will have to make the call. A wet transome and wet stringers/coring can add 400 pounds to these boats. I weighed my transom tearout, and was stunned at what it weighed, over 200 pounds.

If you have to cut the top off the stringer, and put foam in it, I would put 4 layers of 45 degree biaxel 6 oz cloth on it offset by an inch or so to seal it back up. It will be stronger than new.

In any case, I would run some of that down the sides/tabs of the stringers to reinforce the hull to stringer connection. This is a week link in these boats.

The connection/structure points of failure in old seacrafts seem to be
- rub rail joint for the cap/liner/hull
- stringers loose from the floor
- gas tank platform and bulkhead
- transom, they are all shot after 15-20 years
- sole/liner to stringer connection
- floor/deck/lid coring

[Happi1fla]

JohnB, Alex and Ebeach and all others thank you for your help and experience , after receiving all that info,
sorry for not getting back to you right away , what a huge help this will be , Beers on me.

John