Found bottom blisters, now what?

[BRICH1260]

I kept my boat for the first time in the water, slipped for the first time this year. I really liked the convenience it allows rather than mess with the hassle of trailering and loading and loading at the public ramps each weekend. However, after completing my year end hull cleaning a couple weeks ago, I have now noticed several small pin head sized blisters in the gelcoat primarily under the bilge.

So what do I do now. I had planned on slipping it again next year. Do I just have the blisters repaired with new gelcoat, or bottom paint. I didn`t really want to have to bottom paint the boat as I`ve heard it reduces the value of a trailerable freshwater boat, don't know how accurate that is. But it means that it has to be redone every several years and have heard that it`s not cheap to do or re do. If I do paint I would like to keep it white, the current bottom color.

Has anybody been in a similar situation, if so what did you do. Would you do it again? Any alternatives that I haven't thought about.

 

[tpenfield]

Fix the ones that show. Do a barrier coat on the hull bottom before launching next year.

 

[Thalasso]

If you want to do it right.

You need to break open the blisters.
Pressurized acidic liquid often sprays out. Damage can extend beyond the dome.Use a plastic mallet to tap the laminate all around each blister or blistered area.

Solid laminate will sound sharp, voids will sound dull. Mark the perimeter of suspect areas. After all blisters are open, wash the hull to flush away acidic trickles.

Once the hull dries, grind away the remains of the broken dome with a sanding disc or some other sanding or grinding bit in a drill or rotary tool.

Chamfer the perimeter of every blister to transform it into a shallow dimple. Typically you'll be removing only gel-coat, but if you discover damaged laminate, you'll need to grind this away until you reach healthy laminate. Wetting laminate with a trigger sprayer can help you to differentiate. Damaged or dry laminate will show white fibers while healthy laminate will appear dark and translucent with the fibers not evident.

Anywhere the exposed edge exhibits separation between gel coat and laminate, keep expanding the perimeter. Open any separate voids your sounding discovered and treat these the same way as a blister, dishing them into shallow depressions.

By waiting to fill the blisters right before you launch next season, you take maximum advantage of the potential for the exposed laminate to dry out.
West System 105 is what you will need to finish the job
[h=3]Gelcoat Blister Repair - BoatUS Magazine[/h] www.[B]boat[/B]us.com/.../hull-rx-when-and-how-to-repair-gelcoat-blis.

 

[alldodge]

For a hull to blister this quick you have some manufacture issues, but it's to late to for any help from Chaparral. Agree you need to open them up and jet them dry out, the longer the better, That said, more can show up over the winter season.

Get them open and sand then down and let dry. Use epoxy resin to seal the holes, it will bond to poly or vinyl ester resins. You do need barrier coat as tpenfield mentioned, and while a clean non-painted hull sells for more then a painted one. A rotted out hull sells for a lot less.

As you wait more blisters can show up, it would be best to raise the boat off the trailer to check for them under the bunks. Barrier coat with at least to layers, then bottom paint with your choice of white color

 

[Thalasso]

For a hull to blister this quick you have some manufacture issues, but it's to late to for any help from Chaparral. Agree you need to open them up and jet them dry out, the longer the better, That said, more can show up over the winter season.

Get them open and sand then down and let dry. Use epoxy resin to seal the holes, it will bond to poly or vinyl ester resins. You do need barrier coat as tpenfield mentioned, and while a clean non-painted hull sells for more then a painted one. A rotted out hull sells for a lot less.

As you wait more blisters can show up, it would be best to raise the boat off the trailer to check for them under the bunks. Barrier coat with at least to layers, then bottom paint with your choice of white color

Blisters disappear as the boat dries. In fact they might disappear depending how bad they are a few hours after pulling the boat

 

[alldodge]

Blisters disappear as the boat dries. In fact they might disappear depending how bad they are a few hours after pulling the boat

I'll guess your comment is meant for me instead of the OP due to my remarks being quoted), if that's the case PM me why you think my statements are an issue for your opinion. Not to say your not correct but I have not seen blisters that form one day, would go away over an hour much more a week later.

If your comment is not for me then suggest commenting on such issues the OP should look at more closely so he can use this as a basis for the comment.

This is a forum of opinions, and as such should be taken as opinions unless facts are listed

Otherwise I'll take the quotation of my comment as an opposing opinion only

 

[ondarvr]

Blister repair tends to be one of those all or nothing projects, anything short of a full effort can lead to tremendous disappointment in a few years.

Blisters form by water penetrating the gel coat and laminate, finding water soluable substances and breaking them down, as it breaks them down the water can't pass back out of the laminate as easily so it swells up and becomes a visible blister. While at first you see a few random blisters, over time more will form until much of the surface it covered with them.

Here's the problem with spot repairs, or just doing the currently visible blisters. The entire laminate has absorbed water (all laminates do this), since it obviously developed bisters rather quickly (some never blister) it shows the laminate is very susceptible to them, so over time you should expect more to form. The currenlty visible blisters are just that, they are the ones you can see right now, there are typically many more blister sites in the process of becoming visible, they just haven't reached that point yet. If you just repair what you can see and then apply a barrier coat those not yet visible blisters continue to get larger, although it may slow down the formation, all too often more blisters appear in a year or so.

More blisters showing up over time isn't guaranteed, only likely, and it happens so often that reputable repair shops won't do a half hearted repair because the chances of more blistering is too high.

The correct way to repair blisters is to remove the laminate down to where no more laminate damage is evident, they make laminate peelers designed for this exact purpose. These peelers rapidly remove material to a controlled depth so the surface is kept as uniform as possible, this saves time in rebuilding the surface to where is was before and looking good. Once the bad laminate has been removed the hull is dried, sometimes it takes a very long time to ensure the moisture content is low enough so more issues don't haunt you later. At that time the surface is rebuilt, the amount of work in this segment is determined by how much material was removed. Most of this work is done with epoxy, and then an epoxy barrier coat is used to help prevent water from being absorbed in the future.

To do the repair correctly can be pricy and time consuming, so many people opt for the spot repair route, it occasionally works, but if the boat is kept in the water it normally needs to be done again in the future because more blister form..