Light coming through fiberglass repair - SailNet Community
 
LinkBack Thread Tools
post #1 of 4 Old 07-30-2012 Thread Starter
Learning to sail
 
Join Date: Aug 2010
Location: San Francisco Bay Area
Posts: 116
Thanks: 1
Thanked 2 Times in 2 Posts
Rep Power: 5
 
Light coming through fiberglass repair

I patched a hole from an old knotmeter in my exterior cockpit bulkhead with fiberglass CSM and cloth and West Marine Polyester "Boater's Resin," with WM Finish Gelcoat on the outside.

The problem is that the finished repair is translucent. The sunlight outside can be seen inside, and if a bright light is on inside, you can see the outline of the repair outside.

The color of my repair is golden yellow, and translucent, whereas the old fiberglass was fairly opaque and brown-purple.

Why did this happen? Is this going to be a problem, such as by allowing UV infiltration which could weaken the fiberglass? Do I need a thicker layer of gelcoat? (I drilled out a section for a new instrument, and it looks like my gelcoat is actually thicker than the original gelcoat.)
aaronwindward is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 4 Old 07-30-2012
Aspiring to be a Mexican
 
sww914's Avatar
 
Join Date: Oct 2008
Location: La Cruz de Hunacaxtle, Mexico
Posts: 542
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 7
 
Re: Light coming through fiberglass repair

My boat's the same way and the hull's an inch thick.
sww914 is offline  
Quote Quick Reply Share with Facebook
post #3 of 4 Old 07-30-2012
Reward for lost Kraken!
 
hellosailor's Avatar
 
Join Date: Apr 2006
Posts: 11,481
Thanks: 5
Thanked 132 Times in 129 Posts
Rep Power: 11
   
Re: Light coming through fiberglass repair

aaron, you forgot to buy marine grade photon-inhibitor additive, which would slow down the photons coming through your new work.

No, seriously...FRP is normally translucent. There are additives, fillers, dyes, added to make up the color. If the exterior gelcoat you applied is the same "white" as the bulkhead when viewed with reflected light, then that's fine. Just add some opaque layer on the inside, i.e. a couple of coats of black or gray primer or other paint should stop the light from showing through. Ideally you'd go back and add an opaque additive/filler to the FRP, but painting over it will be just fine. By all means, match the color of the existing stuff as a top coat if you will be looking at it.
hellosailor is offline  
Quote Quick Reply Share with Facebook
post #4 of 4 Old 07-30-2012
On the hard
 
CharlieCobra's Avatar
 
Join Date: May 2006
Location: Bellingham, WA.
Posts: 3,503
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 11
   
Re: Light coming through fiberglass repair

A lot of it depends on the resin color. The resin we use is purple when cured so it doesn't allow as much light through.

Baggett and Sons Marine Restoration
The Landing at Colony Wharf
Bellingham, WA.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CharlieCobra is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

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
First Fiberglass repair i_amcdn Gear & Maintenance 32 08-01-2012 10:28 AM
fiberglass repair hertfordnc General Discussion (sailing related) 21 08-21-2009 08:12 PM
serious fiberglass repair- help hertfordnc Sailboat Design and Construction 11 07-09-2009 11:21 PM
Light coming through fiberglass labestia Boat Review and Purchase Forum 15 03-12-2009 01:36 AM
Fiberglass repair the right way? davidpm Gear & Maintenance 31 12-08-2007 02:15 PM

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