DIY Barrier Coat - Page 3 - SailNet Community
Reply
 
LinkBack Thread Tools
post #21 of 40 Old 11-23-2009 Thread Starter
Member
 
mrybas's Avatar
 
Join Date: Jun 2008
Posts: 85
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 8
 
Excellent info everyone. Thanks to your help, I feel more than confident about taking on this project. Time to remove that old bottom paint and see what lies beneath! Can anyone recommend a soda blaster in the Philadelphia area? How about a moisture meter?
mrybas is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #22 of 40 Old 11-23-2009
Senior Member
 
Maine Sail's Avatar
 
Join Date: Jan 2003
Location: Maine Coast
Posts: 5,890
Thanks: 20
Thanked 223 Times in 170 Posts
Rep Power: 16
       
Quote:
Originally Posted by mrybas View Post
How about a moisture meter?

Read this: The Electrophysics CT-33 Moisture Meter

This is about where you want to see your hull readings. Any reading under 7 or so, on this particular meter, is in the proper range for barrier coating. Interlux wants to see moisture content under .5% if you call them and ask tech support. They say "Hull must be dry." in their literature but then don't really define it unless you call and ask..


______
-Maine Sail / CS-36T


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




© Images In Posts Property of Compass Marine Inc.



Last edited by Maine Sail; 11-23-2009 at 10:25 PM.
Maine Sail is offline  
Quote Quick Reply Share with Facebook
post #23 of 40 Old 11-23-2009
Call me Ishmael
 
blowinstink's Avatar
 
Join Date: Sep 2007
Posts: 579
Thanks: 5
Thanked 13 Times in 13 Posts
Rep Power: 9
 
Mrybas -
I'll PM you in a second. I have been talking to a couple of soda blasters in the Phila area -- at least one of whom seems reasonably priced. Maybe we can talk tomorrow.
blowinstink is online now  
Quote Quick Reply Share with Facebook
post #24 of 40 Old 11-25-2009
STARBOARD!!
 
KeelHaulin's Avatar
 
Join Date: Mar 2006
Posts: 1,662
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 11
   
If you soda blast; be sure you pressure wash the hull after and sand it smooth. The pitting that soda or sandblasting leaves can cause further blistering if it is not sanded off. One way to prevent this is to blast it down until only a thin layer of paint (primer) is left on the hull and then sand that off to get down to gelcoat.

I used straight epoxy to barrier coat; a bit more difficult to apply (limited working time and must change rollers) but once you get a thick film it is more water resistant than the barrier coat paint. You can go to MAS Epoxies website for info on how to do a barrier coat with epoxy. For fairing blisters you can thicken epoxy with silica, microballoons, and glass fiber; again go to MAS website for a recipe. Sand it flat 24-48 hours after it sets or it will be difficult to sand smooth after the epoxy fully cures.
KeelHaulin is offline  
Quote Quick Reply Share with Facebook
post #25 of 40 Old 11-25-2009
Telstar 28
 
sailingdog's Avatar
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 15 Times in 12 Posts
Rep Power: 14
         
Properly done, sodablasting should remove the paint but not pit the surface...

Quote:
Originally Posted by KeelHaulin View Post
If you soda blast; be sure you pressure wash the hull after and sand it smooth. The pitting that soda or sandblasting leaves can cause further blistering if it is not sanded off. One way to prevent this is to blast it down until only a thin layer of paint (primer) is left on the hull and then sand that off to get down to gelcoat.

I used straight epoxy to barrier coat; a bit more difficult to apply (limited working time and must change rollers) but once you get a thick film it is more water resistant than the barrier coat paint. You can go to MAS Epoxies website for info on how to do a barrier coat with epoxy. For fairing blisters you can thicken epoxy with silica, microballoons, and glass fiber; again go to MAS website for a recipe. Sand it flat 24-48 hours after it sets or it will be difficult to sand smooth after the epoxy fully cures.

Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
sailingdog is offline  
Quote Quick Reply Share with Facebook
post #26 of 40 Old 11-25-2009
kitejunkie
Guest
 
Posts: n/a
...

Last edited by kitejunkie; 12-26-2009 at 04:28 PM.
 
Quote Quick Reply Share with Facebook
post #27 of 40 Old 11-25-2009
STARBOARD!!
 
KeelHaulin's Avatar
 
Join Date: Mar 2006
Posts: 1,662
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 11
   
Quote:
Originally Posted by kitejunkie View Post
to yeild the full benefit of a barrier coat, as opposed to multiple layers, as one one molecularly "thick" coat is better than a bunch of molecularly thin coats. Not to mention the time factor for one coat to cure plus the sanding/blush removal, fuggettaboutit. this also holds true through the application of bottom coat to new barrier coat, although I'm not sure it really matters between bottom coats after first bottom coat goes on new barrier.
If you are referring to epoxy barrier coating; it is done in the same manner that paint barrier coating is. You apply multiple hot coats of epoxy with a roller; then tie-coat it with one coat of barrier coat paint. I put 6 coats of straight non-blushing epoxy on and it yielded a ~1/32" film of solid epoxy.

SD-

Was talking about the pitting on a microscopic level; a sanded finish won't leave pitting and porosity in the gelcoat like a blasted finish will. That's why sanding after blasting would be a good idea.
KeelHaulin is offline  
Quote Quick Reply Share with Facebook
post #28 of 40 Old 11-25-2009
Senior Member
 
T37Chef's Avatar
 
Join Date: Oct 2006
Location: Maryland
Posts: 4,510
Thanks: 80
Thanked 56 Times in 40 Posts
Rep Power: 9
 
Quote:
Originally Posted by kitejunkie View Post
chef, great photo documentary there after seeing your post it occured to me that you were docked behind me at balt city dock this past weekend, beatutifull boat btw. great weather, and a hell of a sail outta there late sunday night, my son was sound asleep below while I took a beating sailing back to middle river.
Double thanks KJ, it was a great weekend, I consider myself very lucky to have had such great weather We enjoyed a perfect sail out the river into Rock Creek. I wanted to keep going but we had to get back home. What boat are you sailing? You were in front of us...cool, wish I had known, would have offered you a brew

(Please excuse the off topic post )

Cheers,
Shawn

S/V Windgeist
1982 Tartan 37C

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
T37Chef is offline  
Quote Quick Reply Share with Facebook
post #29 of 40 Old 11-25-2009
kitejunkie
Guest
 
Posts: n/a
...

Last edited by kitejunkie; 12-26-2009 at 04:27 PM.
 
Quote Quick Reply Share with Facebook
post #30 of 40 Old 11-30-2009 Thread Starter
Member
 
mrybas's Avatar
 
Join Date: Jun 2008
Posts: 85
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 8
 
So after getting 3 quotes in the neighborhood of $2,000 to have the old bottom paint removed via soda blasting, I decided to see how much effort was required to remove it by hand. So I headed to the boat shed with belt sander, orbital sander, scraper, and razorblades in tow. To my surprise, my first weapon of choice (home depot hand scraper) removed the two old layers of blue and red bottom paint without too much protest. I guess it took about 40 minutes to remove a 3'x3' area....which leads me to believe I could strip the whole thing in 3-4 long days. Verdict: Crank up the IPod and start scraping- $2,000 will come in handy else where!
This leads me to the discovery that I made during my foray into the bottom paint: Blisters....and lots of them, albeit tiny. The 3'x3' area I uncovered was the texture of a golf ball in reverse (maybe not quite the frequency of bumps but about the size, maybe slightly smaller). When applying pressure with my finger nail, some of the blisters would emit a tiny amount of clear liquid (almost unable to be seen with the naked eye.) If it turns out that the entire bottom is covered with blisters (imagine golf-ball-like gelcoat), what course of action should I take? Sand the gelcoat smooth until all blisters are popped and then take moisture readings until satisfactory, then barrier coat?
mrybas 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
Barrier Coat & Antifouling paint shipley Gear & Maintenance 7 08-09-2009 09:18 AM
Barrier coat jerzy0129 Gear & Maintenance 4 02-23-2006 06:42 AM
Is Vinyl Antifoul better over Epoxy Barrier Coat pds Gear & Maintenance 3 08-27-2001 12:27 PM
Barrier Coat stupidgringo Gear & Maintenance 0 08-23-2001 04:53 PM
Epoxy Barrier coat stevemorrell General Discussion (sailing related) 3 11-07-2000 02:13 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