Hull Blisters - need repair?

[pec2402]

04' Larson SEI that spent its first season docked on the river last summer. Noticed approx 7-8 quarter sized blisters after I pulled her from dry docked storage yesterday. I'm planning to trailer the boat this summer because I didn't get much benefit compared to cost with the boat on the water last season, but nevertheless, I have a few blisters that I could use some advice on.

Do these need to be fixed immediately? Any idea how they were caused? The spots seem to be in random places, on both sides of the hull below the water line. I have read through some forums, but I figured I'd start my own thread and provide pics. Any help is greatly appreciated.

 

[tpenfield]

Re: Hull Blisters - need repair?

You should fix them as they will only get worse and more plentiful. They are caused by constant immersion in water.

You should have a barrier coat for long term mooring in water, etc.

 

[chriscraft254]

Re: Hull Blisters - need repair?

I will add to the question, do the blisters really need to be repaired if it is going to be a trailered boat and not left in the water for long periods of time? What is the long term effect or damage expected from a few blisters?

 

[Woodonglass]

Re: Hull Blisters - need repair?

If you're gunna start trailering the boat, I wouldn't bother with em. If any of em break open then repair as needed. Dremel out the area and either fill with Marine Tex or Mix your own resin and then Gelcoat paste.

 

[ondarvr]

Re: Hull Blisters - need repair?

I wouldn't bother fixing them at this time. Blister repairs need to be an all or nothing project, you either remove all the gel coat and affected laminate from below the water and rebuild it with epoxy, or do nothing, in between methods tend to fail rather soon.

 

[Yacht Dr.]

Re: Hull Blisters - need repair?

I personally would fix the repairs as soon as possible.

Just me though .. I would grind out the repairs and fix them NOW.

I mean .. why wait for the repairs to get bigger ? .. I dunno . just me I guess.

YD.

 

[ondarvr]

Re: Hull Blisters - need repair?

The reason for doing nothing is that if these are actual osmotic type blisters then these are just the first of many that will show up, over time almost the entire hull surface will be covered with them. To go through the cost and hassle of repairing just a few is of little value if in six months there will be twice as many new ones. If the boat is left on the trailer there is the possibility that they will shrink back down as the water escapes, which will serve about the same purpose as fixing them, only cost nothing.

There is no harm in leaving them the way they are now and waiting to see what happens. Also re-read my prior post.

 

[Yacht Dr.]

Re: Hull Blisters - need repair?

The reason for doing nothing is that if these are actual osmotic type blisters then these are just the first of many that will show up, over time almost the entire hull surface will be covered with them. To go through the cost and hassle of repairing just a few is of little value if in six months there will be twice as many new ones. If the boat is left on the trailer there is the possibility that they will shrink back down as the water escapes, which will serve about the same purpose as fixing them, only cost nothing.

There is no harm in leaving them the way they are now and waiting to see what happens. Also re-read my prior post.

So delaminated gel is going to be fine after the Water is removed in the blisters ?? um .. K ..

Lets let blisters of that size just shrink back down to a bonded surface and then everything is great.

YD.

PS. I think this is a setup for me ..
PSS. There is no possibility of blisters Re-bonding themselves ..

 

[ondarvr]

Re: Hull Blisters - need repair?

Again, please don't put words in my mouth, or take what I said out of context.

I never said in any way that somehow the blistered glass was going to re-bond itself to the laminate, you made that up and then attributed it to me.

Blisters like these rarely become a structural issue, so while they aren't nice to look at, they really aren't a problem at this point.

If he fixes them now it may just be a waste of time and money because more may form. If more don't form over the next season or so and he doesn't plan to leave it in the water, then he can fix them with a better chance of not having more show up.

The only sure method of repairing a blistered hull is to remove all the gel coat and blistered laminate below the waterline and then rebuild the surface with epoxy. Blisters don't stop at just a few unless there are other reasons for them, which at this point we don't know.

So it’s up to him, he can fix these and watch for more as time goes by, or wait and find out just what he’s up against and fix what may or may not show up in the near future.


Seems like I keep repeating myself doesn't it, and I still get misquoted.

 

[chriscraft254]

Re: Hull Blisters - need repair?

If it is from osmosis,then the blisters wont get better just by leaving them alone, probably won't shink at all just by leaving it out of the water. A few dimples is no reason for immediate concern, but if it turns into the pox, you got issues, delamination is a real threat then. Better actually to address this in the off season so you can grind them off and let the boat dry a couple months before repairing. The boat needs to be dried inside and out for a solid repair and yes epoxy is the way to go..

 

[ondarvr]

Re: Hull Blisters - need repair?

Blisters don't get better, as in repair themselves, but they frequently become less noticeable when left out of the water for a period of time because water may slowly escape from the blister and they shrink. They will begin to swell again the longer the boat is left in the water though.

 

[Yacht Dr.]

Re: Hull Blisters - need repair?

So delaminated gel is going to be fine after the Water is removed in the blisters ?? um .. K ..

Lets let blisters of that size just shrink back down to a bonded surface and then everything is great.

YD.

PS. I think this is a setup for me ..
PSS. There is no possibility of blisters Re-bonding themselves ..

Again, please don't put words in my mouth, or take what I said out of context.

I never said in any way that somehow the blistered glass was going to re-bond itself to the laminate, you made that up and then attributed it to me.

Blisters like these rarely become a structural issue, so while they aren't nice to look at, they really aren't a problem at this point.

If he fixes them now it may just be a waste of time and money because more may form. If more don't form over the next season or so and he doesn't plan to leave it in the water, then he can fix them with a better chance of not having more show up.

The only sure method of repairing a blistered hull is to remove all the gel coat and blistered laminate below the waterline and then rebuild the surface with epoxy. Blisters don't stop at just a few unless there are other reasons for them, which at this point we don't know.

So it’s up to him, he can fix these and watch for more as time goes by, or wait and find out just what he’s up against and fix what may or may not show up in the near future.


Seems like I keep repeating myself doesn't it, and I still get misquoted.

The reason for doing nothing is that if these are actual osmotic type blisters then these are just the first of many that will show up, over time almost the entire hull surface will be covered with them. To go through the cost and hassle of repairing just a few is of little value if in six months there will be twice as many new ones. If the boat is left on the trailer there is the possibility that they will shrink back down as the water escapes, which will serve about the same purpose as fixing them, only cost nothing.

There is no harm in leaving them the way they are now and waiting to see what happens. Also re-read my prior post.

K. .. Im not not sure what you mean by "shrinking back down as the water escapes" in which will 'serve' the 'same purose as fixing" .. some Might be confused as what you are suggesting .. no cost ??

Blisters don't get better, as in repair themselves, but they frequently become less noticeable when left out of the water for a period of time because water may slowly escape from the blister and they shrink. They will begin up swell again the longer the boat is left in the water though.

Again .. I would suggest you Fix the problem Now .. or not. At least find out what the problem came from and then address the issue. ..

There is NO possible or probible .. there is only the What is happining and Why ! Then go from there .

YD.

 

[ondarvr]

Re: Hull Blisters - need repair?

YD

I think you totally misunderstand what an osmotic blister is, how they progress over time and the correct repair proceedure. Do some research on the subject and your questions will be answered.

 

[ondarvr]

Re: Hull Blisters - need repair?

Here is a link to a pretty good description and repair method.


Blister & Laminate Hydrolysis in Fiberglass Boat Hulls

 

[pauloman]

Re: Hull Blisters - need repair?

how to repair at Hull Blister Repair Options - Fiberglass Boat Repair - Boat Pox

that said, the blisters will never sink or threaten your boat. And these may be the first of many.
Enjoy the boating season and re-think the issue in the fall.

paul

 

[Yacht Dr.]

Re: Hull Blisters - need repair?

YD

I think you totally misunderstand what an osmotic blister is, how they progress over time and the correct repair proceedure. Do some research on the subject and your questions will be answered.

Actually I do understand what Blistering is all about. .. I suggest doing the repair NOW .. not later ..

If you have a full blown failure due to missing the times on the said application(s) of that particular boat build then yea.. you need to strip it down to the glass....

I dont misunderstand anythging when I see it .. or start to grind into it ..

Its one of 2 things .. Its not proper prep from the factory .. or its another repair ..

Simple as that mate.

We do NOT understand the Why or When until we apply some sandpaper to get at Why the stuff failed ! .. I can tell when the 'Window' was not met.. I can tell you if you have a Friday boat .. I can tell you lots of things just by getting into it.

I cant tell you what is up with anything unless I was THERE ... I just cant say for sure ..

YD.

 

[ondarvr]

Re: Hull Blisters - need repair?

From the repair guys point of view, doing it now....and then possibly again later works out well, he gets paid the first time and then possibly a second time. This time redoing much of the original repair again. There is no real benefit to the owner to rush right out and get it fixed in this situation since the boat is no longer being kept in the water.

 

[chriscraft254]

Re: Hull Blisters - need repair?

From what I understand the water that is sucked into the hull and causes bubbles is due to a gas mixture pocket in the layup and the water then becomes part of or more dense than water therfore not allowing it to weep back out causing pressure which causes the bubbles in the gelcoat. I wonder if anyone has tried to solidify the bubbles by drilling a weep hole in each one, allowing it to dry out and then injecting epoxy by use of a syringe into them. Wouldn't take care of the cosmetic issue though. I think that might stop the spread or them getting larger over time and might be alot less work than grinding them out and repair. Definately easier than stripping the entire hull.

 

[zool]

Re: Hull Blisters - need repair?

Just from a tinting point of view, If the condition is perpetual, meaning its a progressive problem, it would make sense to let it play out, and repair the largest area one time, as opposed to a patchwork of blends, chasing a substrate problem.

And if it ends up as a redo, then all the better for a uniformed aging of the finish going forward.

 

[Woodonglass]

Re: Hull Blisters - need repair?

In case anyone's interested...The OP has never responded since his original post. IMHO this Horse is dead!