maybe dumb blister question - SailNet Community
 
LinkBack Thread Tools
post #1 of 2 Old 09-01-2001 Thread Starter
Junior Member
 
Join Date: Jul 2001
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
maybe dumb blister question

much of my recent boat shopping has led me to be interested in Pearsons, 30 to 36 feet, probably early 1980''s vintage. many of these boats are advertised as having a recent epoxy job on bottom. is it fair to assume that most Pearsons (as well as most other boats) in that age bracket will have gel coat problems? and if so, would i actually do better to shop for a boat that has had this problem, but corrected by a reputable boatyard?
bruce123 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 2 Old 09-01-2001
Moderator
 
Jeff_H's Avatar
 
Join Date: Feb 2000
Location: Annapolis, Md
Posts: 6,816
Thanks: 5
Thanked 133 Times in 106 Posts
Rep Power: 10
     
maybe dumb blister question

A large percentage of US boats built in the late 1970''s and early 1980''s have had blister problems. I really do not know whether Pearsons of this era were consistant to this pattern. There are a number of causes of blisters during this era: 1. poor adhesion of the gelcoat to the lamimate, 2. Deterioration of the resin within the laminate due to contact with water molecules from the EXTERIOR of the hull with by-products of the catalytic process (True osmostic blisters), 3. Deterioration of the resin within the laminate due to contact with water molecules from the INTERIOR of the hull with by-products of the catalytic process, and 4. Resins that produced byproducts during catalyzation that are self-destructive to the resin or resin/fiber bond. I have listed these in order of difficulty to permanently repair.

The problem with gelcoat to laminate bomd has to do with the change in gelcoat formulation in the 1970''s. This new gelcoat was thinner, shinnier and apparently set up more quickly. This made it harder to get a bond between the laminate and the gelcoat. These are very shallow blisters and the gelcoat can be peeled off almost in sheets. the laminate below will appear smooth and shiny and nearly perfect. Breathe a sigh of relief; you have ducked the bullet. It is easy to repair this permanently by removing the loose areas of gelcoat, sanding the laminate lightly and clean the surface well. Then apply either an epoxy or vinylester barrier coat built back to the thickness of the original gelcoat or a bit more and you should be done for life.

Situaltion 2 and 3 come from similar causes but it is much easier to perform a permanent repair when the water is entering from outside the hull and the damage to the laminate tends to be shallower ad easier to fix. When the blisering comes from interior moisture there is almost nothing that you can do to make a permanent repair.

In the case of 4 where the self distructive reactions are a by-products of the materials involved there is absolutely nothing you can do to stop the process and over time the materials will also loose significant strength.

I have no idea what you should expect on ewarly 1980''s era Pearsons.

Regards
Jeff
Jeff_H is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Ladder question mcain Gear & Maintenance 14 08-03-2007 10:28 PM
GPS question wallm General Discussion (sailing related) 13 05-30-2004 02:10 AM
Rudder repair, blister & more Burnsy Gear & Maintenance 0 03-07-2004 06:46 PM
question on sails Mark_OD23 General Discussion (sailing related) 6 11-19-2002 04:41 PM
Valiant Blister History? VIEXILE Boat Review and Purchase Forum 3 06-08-2001 02:33 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome