hull crack

[lawrence3479]

Discovered a hull stress crack port side near the sailboat stand pad. Looking inside it appears the port engine wall panel that forms the port sette wall is the culprit. It looks like stress on the tabbing caused the crack to form. On my boat all the tabbing on this panel is engine compartment side. Looking under the port settee no tabbing had been applied. Moderate sanding on the exterior shows the crack penetrating into the fiberglass. I'd like to know whether I should remove tabbing on the engine side and repair, or just add additional tabbing to the sette side, and hope that by reinforcing the bulkhead along the area I'll prevent any future cracking after repairing the exterior. The cracks about 12" long. On the plus side I have fairly good access to the interior area, and the spring repair list has become very focused with this one project. Any feedback is welcome!
Cheers
Larry

 

[CalebD]

A picture or two and knowing what year and model of boat it is might help a lot.
It is also hard to say without knowing whether the crack is just a hairline crack or worse.
It does not sound life threatening to me but seeing is believing.

 

[Ross]

Gelcoat cracks easily, fiberglass usually just bends alot. You may have a hard spot at that bulkhead. Pictures as stated are helpful. Broken fiberglass shows alot of white around the broken fibers.

 

[larry3479]

I spent a couple hours at the boat looking at the crack today. Talk about bummed. Grinding into it, it's at least a 1/4 " deep, and runs along the interior engine wall bulkhead tabbing. It's hairline thin, about 18" long. The fiberglass is white at the crack edges exterior, it is not clear to me yet if it runs completely through the hull or not. On the interior the tabbing engine side of the quater berth wall is intact, quater berth side the area looks to be right along the 90 degree angle formed by the wall. The location of the crack makes sense from what I've read. The question is how to properly repair it. I've done some fiberglass work, rebuilt the mast step, reset the prop shaft, and repaired tabbing in a couple of spots. So, I'm familiar with west epoxy. Should repair the exterior by feathering out the edges of the crack 3-4 inches, and then reglassing, maybe going into the quaterberth and adding new tabbing that side? Should I try kevlar or dynel? Any comments are appreciated.

I took some photos, but I'll try to post them. My boat is a Seidelmann 30T.

Cheers

larry

 

[Chuckbear]

Larry, You need to enlarge the repair area and be sure you have ground down past all damaged cracks. You should grind out 5 inches on all side of the damaged area if this is indeed a crack. grind out and sand the area to a beveled edge. Be careful grinding and use protective clothes and masks. Once done grinding clean up all dust and use a mold release on areas around the patch. Cut you patches about 1 inch larger than the hole and progress down in size making each patch 1 inch smaller that the previous. I like to use about 40 oz. biaxial to make these repairs with West System. You should always use epoxy below the waterline with fiberglass cloth. If the crack is also on the inside you will want to do the same repair on the inside. Lay on the patches and roll out any air bubbles until all of the patches are on and even. Once the exopy has cured you can wash down with soap and water to remove the blush, sand until smooth enough for the gel-coat and then repair the gel-coat. That is kind of basic, but you can find more details on the West System web site. Forget Kevlar or any others unless your current hull is Kevlar re-inforced.

 

[larry3479]

Larry, You need to enlarge the repair area and be sure you have ground down past all damaged cracks. You should grind out 5 inches on all side of the damaged area if this is indeed a crack. grind out and sand the area to a beveled edge. Be careful grinding and use protective clothes and masks. Once done grinding clean up all dust and use a mold release on areas around the patch. Cut you patches about 1 inch larger than the hole and progress down in size making each patch 1 inch smaller that the previous. I like to use about 40 oz. biaxial to make these repairs with West System. You should always use epoxy below the waterline with fiberglass cloth. If the crack is also on the inside you will want to do the same repair on the inside. Lay on the patches and roll out any air bubbles until all of the patches are on and even. Once the exopy has cured you can wash down with soap and water to remove the blush, sand until smooth enough for the gel-coat and then repair the gel-coat. That is kind of basic, but you can find more details on the West System web site. Forget Kevlar or any others unless your current hull is Kevlar re-inforced.

Thanks Chuck,

Yes, I'm certain it is a crack. It's difficult to tell if it goes all the way through as the interior tabbing and bulkhead are almost on top of it. As I start the process of feathering out the exterior crack, it will become apparent whether the crack goes all the way through or not. Most of the interior hull has been painted, would you use a solvent to remove the paint prior to grinding for fiberglass work?

Thanks

Larry

 

[Ross]

Larry , it depends on the type of paint. Try alcohol first. wet a rag and rub, if it comes off, it is latex, if not it is oil based. Then try the stripper that carries the safetest hazard labels. Sooner of later you will be in there with the need for a lot of ventilation, plan for it.

 

[Chuckbear]

Larry, I would not bother removing paint if you plan to sand or grind out the area since that is going to take the paint off and you will want to grind out the repair area completely. No need to do extra work.

 

[larry3479]

Spring Launch

Larry, I would not bother removing paint if you plan to sand or grind out the area since that is going to take the paint off and you will want to grind out the repair area completely. No need to do extra work.

I just launched the boat last Friday, such is the sailing season in New England. Repair to the crack appears to be solid. I did use West System with biaxial tape. The crack did not go through the hull completely, on the interior bulkhead I added new tabbing to the side lacking any. Thanks for all the suggestions and support!

Cheers

larry:dance: