Hull-Deck Joint Damage Repair Question

[opie]

I found damage to my hull-deck joint today and could use a suggestion or two on how to repair it. Thanks for looking at the web page HERE .

Briefly, I removed the rub rail today to find a leak and discovered fiberglass damage to the joint in one place.

One message I do want to leave to the membership here is that a leak coming into the boat should be fixed sooner than later. That means removing the rub rail. Just sealing the joint of the rub rail and the boat may work to hide the problem but it may reappear and in a few cases, like mine, there may be a worsening of the problem if ignored. Plenty of links in the archives here will help you.

[Night Sailor]

Excellent question and excellent article.
From what I can see what I would do is this:
Allow to dry thoroughly. Apply heat lamp or hair dryer to area to speed process.
Grind or scrape out any loose lip material in the damaged area.
Remove any old sealant in this area. Wash thoroughly with acetone or alcohol.
Insert a temporary spacer (a filler piece of cardboard, metal or something the appropriate thickness )coated with wax to keep the space between lips open in the damaged area.
Repair the damaged lip with a strip of epoxy soaked woven fiberglas cloth in as many layers as necessary to achieve the thickness of the original.
After the repair cures, remove spacer.
Grind edges and bottom lip to match contours of adjacent areas.
Coat the area ground with a thin layer of epoxy to seal any loose ends.
Fill space between lips with 3M5200 or 4200, squeezing it in so the whole lip is covered to the inside of the joint.
Allow to cure for the recommended time. Remove any excess caulk.
Replace rubrail.

[opie]

Thanks. I'll try to follow each step. One question though. Would it work as well to epoxy fiberglass the gap solid rather than leave a gap for sealant? Does it need to remain a flexible joint for some reason? I think I'll do it your way anyway, but it would be easier to stuff the gap with wet cloth and epoxy....

[Richard O'Brien]

I'd like to sanction everything Night Sailor said. he seems to have it right, and yes you need to use the urethane caulk. It may seem like a rigid joint, but my experience (pre-cast concrete) with any large mass is that there are no rigid "joints". You would have to layer the entire rub-rail inside and out to eliminate the caulk.

It sure looks like you struck a piling or something pretty hard? Any idea how that happened?

Richard

[Night Sailor]

Opie, I recommended putting it back the way it is for two reasons. First is that in case of some future collision at or near this site, the repair would act the same way as the rest of the hull joints with flexibility and give. Hard spots tend to break out even larger sections of hull material.
Second is that in event of any future damage, it's as easily repaired as any other spot on the joint. After all, the caulk is removeable, albeit reluctantly, as it was designed to do. Not so a solid fusion of glass and epoxy.

If the area of grinding needs to extend far enough to show after the rub rail is installed, search for pictures and text on fiberglass repair showing how edges are feathered, gelcoat applied and finished. There are numerous sites with how to pictures and instructions.

[Don T]

Hello,
I would not glass the joint solid. It will create a hardpoint for stress in the area. Restructuring and resealing is the best course of action IMHO.

[CrPlater]

While you have the rub rail off I suggest you might as well 'shore up' that hull to deck joint.

I bought SS screws and nuts (around 100 each) and and placed in between existing...yielding 2.5" on centers to sqeeze down the deck and hull (some water squeezed out) Electric disc sanded off old 3M 5200 and ground a small 'V' into joint. applied new 5200 and let cure. Took about 8 hours total.