1992 Stratos 2250 here we go again

[Arawak]

Um, if that's foam core construction then the core material is required. Do some research on sandwich structures. Been out of college a long time, but from what I remember the adhesion between the skin and the core material is important too.

You might want to seek some advice on boatdesign.net and bateau.com as well on this one.

I would *guess* that you will need to remove the entire damaged section of glass, and the damaged foam, epoxy new foam where needed and then glass over to rebuild the inner skin. That's a guess... you should really research this and let us know what you find.

 

[jc55]

That large area on the inside of the hull that's delaminating seems to indicate a large area of wet core. You might as well cut a section out from the inside to fix the hole in your outer skin from the inside and outside. This will let you investigate the extent of core damage. I've only read about foam core repairs...I'm curious. There's a lot of info out there but you might really have your work cut out for you,(pun intended). Fingers crossed!

 

[Woodonglass]

Ok, Let's clear some things up. From the pics, I see what looks like a couple of pieces of 1/2" foam that have been layed over the inside of the hull and then had glass layed over them to form kind of a rib to reinforced the hull. This is what I was addressing. Are you saying that your actual hull is a foam "Cored" hull?? If so, then the repair is a whole lot more involved.

 

[Arawak]

From the pics, I see what looks like a couple of pieces of 1/2" foam that have been layed over the inside of the hull and then had glass layed over them to form kind of a rib to reinforced the hull. This is what I was addressing.

Ah, I see what you mean, like a stiffener. Hopefully that's what it is.

 

[Arawak]

You know, a quick call to Stratos might be the easiest way to find out. They might even provide recommendations on the repair.

 

[Woodonglass]

I been thinkin, and that's a Dangerous thing..., but the only foam cored hulls that I've seen personally are sail boats and catamarans. Don't think I've ever seen a boat of this type with a Foam cored hull. But I'm NOT a Pro and never officially been "In the Business" so there's a LOT of room for error. I'll be VERY INTERESTED to find out if this one is. Hurry up and tell us!!!!

 

[ahmincha]

I'm sorry for the confusion I don't explain well they seem to be stiffeners

 

[kcassells]

Well then there ya go. Hopefully an easy fix now. ..............Whew............

 

[kcassells]

You can easily make that repair with foam or some wood.

 

[GT1000000]

Not 100% sure, but that looks like 1/4" X 1" X 1" balsa tiles, laid along the hull to create stiffeners...
Might be wrong and they could be foam, but in the late 80's, early nineties, there was a mixed bag of boat construction techniques due to the new up and coming "foam" products, and the tried and true, read fast and profitable, balsa squares...
I remember seeing some stuff like that on other big glass boats at the marina...
I asked my friend about it and was told that originally, they would slather on a strip of thin PB, set the squares in place, re-wet and tab/laminate to the hull...in a old style production, it was usually done by 2-3 laborers, one following the other...
If any repairs are needed, due to whacking a dock or another boat and punching a hole in the hull...
He has used all types of "cores" to recreate the stiffeners, foam, balsa squares, strips of the appropriate thickness of MG Ply, what ever floats the boat......
They use some really creative ways to temporarily secure the strips of ply in place until they can be "tacked" in place with PB.
Then they slather on the PB and tab into the hull...creates a sort of wood-cored, curve-able/conformable, square beam.
The ones in your pic look almost new...looks like they did a good job of sealing against water intrusion...
You will need to consider your options for complete replacement, they add structural support and help to prevent any flex to the larger, un-supported sections of the hull skin.
If the wood/foam looks that good and the fiberglass looks that nice and pink, I would not mess with it...of course you should still check by removing any gel coat or paint that would prevent you from seeing what is going on underneath.
If there is De-lamination, then yes it will have to be removed and repaired, other wise, grind to good glass and top coat with your preference...
If you need to repair, just use a good resin resistant but compatible core, like back yard boat ply, balsa squares, foam, etc. and rebuild them with some fresh glass...basically copy and repeat what is already there...

 

[ahmincha]

This section was delaminated I tore this off with my bare hands. actually fairly easily. I am 90% they are foam i will look again tomorrow and try to get a better picture of the foam. My plan is to use blue foam to recreate form. is the blue foam compatible with epoxy

 

[Woodonglass]

Yup, that's what's known as end grain balsa core. Lot's of boats have hulls made like that..http://forums.iboats.com/forum/boat...kmate-v-mate-ii-restore?p=3752550#post3752550
You can create basically the same thing by cutting some cardboard tubes in half and laying them down and then glassing over the top of them. It's the design and the glass that does the trick NOT the cardboard or the balsa. If you lay down a couple layers of that 8.5 oz glass with the epoxy over the cardboard tubes after you get the damage repaired you won't have to worry about the hull flexing in that area. Here's an example of how one of our members used 1/2 tubes to stiffen the bow section of his boat. He can stand on it now with NO FLEX.http://forums.iboats.com/forum/boat...mplete-restore-splashed?p=4434050#post4434050

 

[GT1000000]

I have no experience with epoxy resins and any of the foams available...
You might want to do a test on a small section of foam...apply some epoxy, wet a piece of cloth, lay it on and see if the foam retains its shape after it is fully cured...
The cardboard tubes, like WoG said are also an old school way of creating the same thing...
Basically just making a form for the resin/cloth to become a structural member...

 

[Arawak]

I have seen thin wall PVC cut in half used for this too. Would think it would add a little strength as well.

 

[kcassells]

I have no experience with epoxy resins and any of the foams available...
You might want to do a test on a small section of foam...apply some epoxy, wet a piece of cloth, lay it on and see if the foam retains its shape after it is fully cured...
The cardboard tubes, like WoG said are also an old school way of creating the same thing...
Basically just making a form for the resin/cloth to become a structural member...

I do recall that you should be able to use the Home Deblow pink foam for glassing and that it holds up. In addition to that pop some pin holes in it to make a stronger/integral bond. I recall this is only able to be done with EEEEpoxy but give it a test first. Let me know.

 

[zool]

I do recall that you should be able to use the Home Deblow pink foam for glassing and that it holds up. In addition to that pop some pin holes in it to make a stronger/integral bond. I recall this is only able to be done with EEEEpoxy but give it a test first. Let me know.

If you want to know about foam and resin mixes, look to the surfers...

http://www.surfscience.com/topics/surfboard-anatomy/materials/know-your-foam/

Actually, I just posted this for the chic pic.....but the info is there too!

 

[kcassells]

If you want to know about foam and resin mixes, look to the surfers...

http://www.surfscience.com/topics/surfboard-anatomy/materials/know-your-foam/

Actually, I just posted this for the chic pic.....but the info is there too!

Good read Zool and yes the chic pic does help. Also under the "materials" tab is more info for epoxy and foam. Cool! Thanks.

 

[kcassells]

If you go to the end grain balsa..depending on how much you need you can acquire that wood stock at most Hobby shops. Planes, Trains and Automobiles. You actually could just use squared out ply pcs. too.

 

[jc55]

Man, that is great news about the hull not being cored!

 

[kcassells]

Or just plain ply to fit. No brainer.