skin separating from hull below waterline

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UPnorth
Posts: 4
Joined: Thu Aug 29, 2019 6:43 am
Location: Near Houghton Michigan

skin separating from hull below waterline

Post by UPnorth » Wed Sep 04, 2019 7:27 am

This is my first time posting I am about to repair a 2017 Glen-L Titian tug. Attached are photos of the split and separated fiberglass skin. I also attached a pic of water weeping out through the skin.

I am looking for advice on how to approach this. I have ordered the study plans for the Titian tug to better understand how the boat is put together. I have also ordered a fiberglass boat repair book. Are there other things I should look at?

Thanks in advance for your ideas and advice.

UPnorth
water weeping.jpg
split skin.jpg
split skin 2.jpg

TomB
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Joined: Wed Jan 18, 2017 4:07 pm
Location: Holland, MI

Re: skin separating from hull below waterline

Post by TomB » Wed Sep 04, 2019 8:32 am

Have a look at https://boatbuilders.glen-l.com/titan-b ... -canada-2/ or some of the others in the gallery. They will help you understand how the boat was put together.

Tom

hoodman
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Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: skin separating from hull below waterline

Post by hoodman » Wed Sep 04, 2019 8:47 am

I don't think I would have put fiberglass on a solid wood keel. Obviously, everything that is delaminating is going to have to come off.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

UPnorth
Posts: 4
Joined: Thu Aug 29, 2019 6:43 am
Location: Near Houghton Michigan

Re: skin separating from hull below waterline

Post by UPnorth » Wed Sep 04, 2019 9:24 am

Thanks for the link to the Titian construction. Excellent pictures. They help.

What is the standard practice for treating a solid wood keel? The keel wood appears to be sound.

I dont know much about the boat's history other than it was built in 2017. I suspect there will be more surprises.

Thanks again,

JimmY
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Joined: Sat Jul 30, 2016 11:08 am
Location: Brighton, MI

Re: skin separating from hull below waterline

Post by JimmY » Wed Sep 04, 2019 9:42 am

My opinion based on what I've seen done here...

You will need to strip back the fiberglass until you find a solid bond, and then feather the edges for the repair. The wood will need to be re-encapsulated. You may want to look at CPES penetrating epoxy for this. It will soak into the wood and should help stabilize it if there is any rot. Then you can look into re-fiberglassing it.

I agree with Matt on not glassing over a solid wood keel. Keels take a lot of abuse and will sooner or later need to be repaired or replaced. My keel is white oak and was attached after the hull was glassed. So, maybe look at removing the keel, glassing, and re-attaching it. Trying to get a good bond in a sharp, inside corner is difficult. The glass is always trying to flatten out while the epoxy cures and will pull away from the hull.

Do some research on epoxy "systems" since not all epoxies work well with each other and are used for different applications. You will need a structural epoxy is you need to bond anything back together, and a laminating epoxy for encapsulation and glassing. I used System 3 Silver Tip for laminating and glassing, it is a non-blushing epoxy and if you re-coat within 24 hours you don't need to sand it. Other epoxies may need to be sanded between coats. System 3 also appears to have a penetrating epoxy like CPES.

Bottom line, you should be looking how to do hull preparation (encapsulation), fiberglass, prime, and paint.
-Jim
Nothing says poor craftsmanship like wrinkles in your duct tape!

JimmY
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Re: skin separating from hull below waterline

Post by JimmY » Wed Sep 04, 2019 9:43 am

UPnorth wrote:
Wed Sep 04, 2019 9:24 am
What is the standard practice for treating a solid wood keel? The keel wood appears to be sound.
Encapsulate with epoxy, and paint it with the hull.
-Jim
Nothing says poor craftsmanship like wrinkles in your duct tape!

hoodman
Posts: 2249
Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: skin separating from hull below waterline

Post by hoodman » Wed Sep 04, 2019 10:43 am

I doubt it would be practical or necessary to remove the keel. But you're at least going to need to strip the keel and part of the surrounding area back to bare wood, repair any damage, and go from there.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

JimmY
Posts: 838
Joined: Sat Jul 30, 2016 11:08 am
Location: Brighton, MI

Re: skin separating from hull below waterline

Post by JimmY » Thu Sep 05, 2019 7:11 am

Hi UpNorth,

On the short part of the keel, did this boat hit something? There appears to be some damage to keel itself.

On the thicker/taller(?) part of the keel, looking at the drawings of the Titan, this supports the bottom of the rudder and propeller shaft, correct? If this is the case, could the keel be flexing side to side in this area and working the fiberglass loose? When you have fiberglass on an insider corner like that I think you will have problems like this. While epoxy is somewhat flexible, fiberglass does not stretch along its length, so at some point the epoxy can't hold the glass to the hull. Also temperature changes may cause stress in this area.

Knowing a little more about the design, I agree with Matt, that is may not be practical to remove/replace the keel. But I'm still of the opinion that trying to glass an inside corner in this area will be prone to separation. Maybe add a larger radius fillet between the hull and keel, but this may just move the issue elsewhere (fillet now separates). Perhaps cut/sand back the glass over the existing fillet and just encapsulate this area with epoxy and then maybe add add a flexible caulk (3M 5200?) for additional water protection.

Just throwing out some ideas to consider.
-Jim
Nothing says poor craftsmanship like wrinkles in your duct tape!

hoodman
Posts: 2249
Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: skin separating from hull below waterline

Post by hoodman » Thu Sep 05, 2019 3:18 pm

I'm thinking he probably doesn't need to glass the keel at all. The plywood is what needs glass. Solid wood you can just encapsulate with epoxy and paint.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

UPnorth
Posts: 4
Joined: Thu Aug 29, 2019 6:43 am
Location: Near Houghton Michigan

Re: skin separating from hull below waterline

Post by UPnorth » Sun Sep 08, 2019 8:36 am

thank-you for the replies.
I don't think the boat struck anything, but I cant be sure. The keel appears solid. There looks like there might be some patch work in spots, however. I have two ideas on the cause of the problem:
1) The screws holding rubber keel protector at the front of the boat let water leak in, the wood swelled and split fiberglass
and/or
2) trailering the boat from central Wisconsin to upper Michigan stressed the boat.

Is #2 feasible? Seems like these boats are pretty strong?

I have another, probably related, problem with the boat. Water is leaking in and out of the fitting the supports the propeller shaft. The leak is between and fitting and hull, not between the shaft and the fitting. I suspect water is entering the bilge and the keel area here. Any advice on how approach this one?

I will keep you posted as begin to tear into this along the lines of what JimmyY suggested.

Thanks again for your help.
Attachments
ftting leak.jpg

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