International Association of Grand Banks Owners Forum Index
International Association of Grand Banks Owners
 FAQHelp   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 My ProfileMy Profile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
Grand Banks Owners FAQ Forum Grand Banks Owners

Bonding with a wooden hull
Goto page 1, 2  Next
 
Post new topic   Reply to topic  International Association of Grand Banks Owners Forum Index -> Specifications
 
Display posts from previous:      View previous topic :: View next topic  
Author Message
 
  
John O. Anderson
Commitment II
Victoria, BC
1971 GB36
Supporting Member

Joined: 26 Aug 2010
Posts: 5
Victoria, BC

PostPosted: Thu Nov 01, 2012 4:54 pm    Post subject: Bonding with a wooden hull Reply with quote

I own a 1971 GB36 (wooden hull) and in a recent haulout I was advised to connect all the through-hulls to the boat's bonding system - they had been disengaged by the previous owner.
However, reading Nigel Calder I noticed the recommendation (supported by the ABYC) that through-hulls, if isolated from the hull, should not be connected to the boat's bonding system.
Is there a clear and rational position on the bonding (or not) of through-hulls in wooden hulls?

_________________
John Anderson
Victoria, BC
Canada
Back to top
View user's profile Send private message Send e-mail
Frode
Solstice
Long Beach, CA
1969 Classic 36, #103
Supporting Member

Joined: 16 Nov 2002
Posts: 2310
Las Vegas

PostPosted: Thu Nov 01, 2012 6:48 pm    Post subject: Re: Bonding with a wooden hull Reply with quote

John O. Anderson wrote:
Is there a clear and rational position on the bonding (or not) of through-hulls in wooden hulls?

Yes, to both, unfortunately.

Do a search on this forum and you will find we have engaged in these discussions for years, and there are good arguments for going either way.

I personally had everything bonded when I bought the boat, but disconnected everything several years ago. Every through-hull appears to be as sound today as it was back then, and I have gotten rid off all the nasty, nasty burns in the hull planking every place the bare copper strip had touched, and around every through-hull.

_________________
Frode
[url]www.grandrestoration.com[/url]
Back to top
View user's profile Send private message
Tom Overs
Little Ship
Portavadie Scotland
1973
Supporting Member

Joined: 24 May 2002
Posts: 2906
England

PostPosted: Fri Nov 02, 2012 4:26 am    Post subject: Reply with quote

I'm with Frode on this one, I had some chemical decay showing around a through hull so I disconnected the bonding, it has now been stable for about 3 years.

I'm not sure anybody can give a definitive answer to this one but this may help.

http://www.mgduff.co.uk/

Tom

_________________
GB32-390
"Little Ship"

Born to cruise...........once forced to work!
Back to top
View user's profile Send private message Visit poster's website
grich737



Supporting Member

Joined: 25 Sep 2005
Posts: 1501
coeurdalene ID USA

PostPosted: Fri Nov 02, 2012 7:28 am    Post subject: Reply with quote

Same thing with us, removed the bonding and everything has been stable since
Back to top
View user's profile Send private message Send e-mail
Paul Headland
Tara Explorer
La Napoule (France)
GB42 CL 1969 #74
Supporting Member

Joined: 22 Nov 2003
Posts: 159
United Kingdom

PostPosted: Fri Nov 02, 2012 7:38 am    Post subject: Reply with quote

And me...

Been disconnected for 12 years now & no issues, except no plank degradation, which is good as we had to change several due to softening around the seacocks.
Back to top
View user's profile Send private message
Stretch Head
Heads Up
Los Angeles, CA
1966 42 Classic -17
Supporting Member

Joined: 21 May 2002
Posts: 3562
Wilmington, CA. USA

PostPosted: Fri Nov 02, 2012 8:17 am    Post subject: Reply with quote

when I bought my boat all thru hull fittings were bonded. I have an ElectroGuard system and it wasn't working correctly. After consulting with many people I put new grounding wire of heavier gauge and I didn't connect the thru hull fittings per their recommendations.

The only fitting I have replaced in 22 years is for the bait tank. All the rest are fine.

_________________
Capt Head
GB42-17 Classic Cockpit Model

My personal Banned List; All Polyester resins, Silicone, Bondo and sea sick crew.
Back to top
View user's profile Send private message Visit poster's website Yahoo Messenger
John O. Anderson
Commitment II
Victoria, BC
1971 GB36
Supporting Member

Joined: 26 Aug 2010
Posts: 5
Victoria, BC

PostPosted: Fri Nov 02, 2012 5:45 pm    Post subject: Reply with quote

Thank you all for your views and experiences - looks like non-bonded through-hulls for wooden hulls is the preferred approach.

John

_________________
John Anderson
Victoria, BC
Canada
Back to top
View user's profile Send private message Send e-mail
Tom H
Schatzi
Guilford, CT
1976 GB Classic #482
Supporting Member

Joined: 04 Sep 2003
Posts: 839
Dunwoody, Georgia, USA

PostPosted: Fri Nov 02, 2012 9:09 pm    Post subject: Reply with quote

To my way of thinking this would also apply to FG boats as well. Six years ago I had the yard replace all my thru hulls and when they were done they had not replaced any of the bonding wire. I questioned this and was told that the bonding was not needed for the thru hulls. I check my thru hulls frequently and in the six years since have not noticed any deterioration. The only zincs I have are two on each shaft and the pencil zincs in the heat exchangers. The boat is 36 years old and the metal parts still look good.
_________________
Best regards
Tom Hansen
1976 42' GBC #482
"Schatzi"
Back to top
View user's profile Send private message Send e-mail
Bob Lowe
DREAMER
Oak Harbor WA
45' Alaskan 1974
Supporting Member

Joined: 28 Apr 1999
Posts: 13156
Mexico

PostPosted: Sat Nov 03, 2012 7:36 am    Post subject: Reply with quote

The biggest problem with the bonding systems on wood GBs is that the copper strap was not insulated from the wood when installed. As result, caustic salts form along the strap as well as around though hull fittings, and will eat the wood a bit over the years. It is customary to neutralize the caustic salts with white vinegar and rinse with a borax and warm water solution once or twice a year.

Generally, bonding and zinc anodes are used in a situation where there are dissimilar metals, either between parts or within metals. The GB woodies generally had all good quality bronze below the water. In that situation, one can get by without bonding and zinc anodes.

If you have SS shafts and other underwater metals not bronze, it is advisable to install an insulated bonding system and zinc anodes. This applies to fiberglass boats as well.

_________________
Good luck,
Bob Lowe
Back to top
View user's profile Send private message Visit poster's website
binkleylane
AmazIng Grace
Ruskin, Florida
1968 Grand Banks Alaskan

Joined: 13 Sep 2015
Posts: 15

PostPosted: Sun Jan 31, 2016 4:36 pm    Post subject: Reply with quote

[quote="Bob Lowe"]The biggest problem with the bonding systems on wood GBs is that the copper strap was not insulated from the wood when installed. As result, caustic salts form along the strap as well as around though hull fittings, and will eat the wood a bit over the years. It is customary to neutralize the caustic salts with white vinegar and rinse with a borax and warm water solution once or twice a year.

Generally, bonding and zinc anodes are used in a situation where there are dissimilar metals, either between parts or within metals. The GB woodies generally had all good quality bronze below the water. In that situation, one can get by without bonding and zinc anodes.

If you have SS shafts and other underwater metals not bronze, it is advisable to install an insulated bonding system and zinc anodes. This applies to fiberglass boats as well.[/quote

Hi Bob,
I am in the process of buying a GB46 Alaskan - hull 8 / 1968.
In my preliminary inspection I found what you described in the above post.
The bonding strap aft appears to be nailed directly to the stringer and there seems to be "hair" on the stringer adjacent. I suppose this is the top layers of the wood reacting to the chemical action you described. The thru hulls are bonded to this system.
The boat has always been in salt water and is now located in SW Florida.
Should I be worried?
Your recommendations please.

Bob
Back to top
View user's profile Send private message
Bob Lowe
DREAMER
Oak Harbor WA
45' Alaskan 1974
Supporting Member

Joined: 28 Apr 1999
Posts: 13156
Mexico

PostPosted: Sun Jan 31, 2016 8:28 pm    Post subject: Reply with quote

Removing the copper strap, cleaning the caustic salts up and neutralizing with vinegar and Borax solution is a good start.

If you have all good bronze under water, you may not need to bond. The above will be a good start.

_________________
Good luck,
Bob Lowe
Back to top
View user's profile Send private message Visit poster's website
binkleylane
AmazIng Grace
Ruskin, Florida
1968 Grand Banks Alaskan

Joined: 13 Sep 2015
Posts: 15

PostPosted: Sun Jan 31, 2016 9:58 pm    Post subject: Reply with quote

Thanks Bob.
Survey is most likely this week. I will make sure they pay special attention to the thru hulls and other suspect compenets.
First big wood boat and this is one area that really worries me and that is due to the fact that I do not yet know enough about it to understand the process.
I really value your experience and appreciate your time and advice.

Fair winds
Bob
Back to top
View user's profile Send private message
Keith Morris

Manchester WA

Supporting Member

Joined: 12 Feb 2002
Posts: 1745
Manchester, WA

PostPosted: Sun Jan 31, 2016 11:36 pm    Post subject: Reply with quote

We found extensive burning at the bronze thru hulls on the survey when we bought our boat back. At the suggestion of our surveyor, we have unbonded everything. We have also installed an isolation transformer among other things. I have other GB woody friends that have completely removed all of bonding with excellent results. We will be hauling out this spring and will check to see how the prop, rudder, and shoe zincs are holding up and also watch the thru hulls to see how they are doing. We have to remove and eliminate a thru hull and drill a 3" hole to plug where the burned wood was.
_________________
Keith
Back to top
View user's profile Send private message
binkleylane
AmazIng Grace
Ruskin, Florida
1968 Grand Banks Alaskan

Joined: 13 Sep 2015
Posts: 15

PostPosted: Mon Feb 01, 2016 7:42 am    Post subject: Reply with quote

Thanks for the input. I am going to do the same and have a corrosion survey/electrical survey completed. The boat is bonded at this time and I will have the fittings and adjacent hull areas looked at very closely.
I would imagine the exhaust thru hulls would also be effected.
Updates as I get them.
Again the value of this venue has proven itself.
Do you or have you noticed the "hair" issue that I mentioned previously.

Bob
Back to top
View user's profile Send private message
Bob Lowe
DREAMER
Oak Harbor WA
45' Alaskan 1974
Supporting Member

Joined: 28 Apr 1999
Posts: 13156
Mexico

PostPosted: Mon Feb 01, 2016 10:01 am    Post subject: Reply with quote

The "hair" issue could be a different problem if on the inside of the lower planking.

I have had good luck with arresting that sort of issue with white vinegar and a hard scrubbing followed by a warm water & Borax treatment to neutralize, again with hard scrubbing. Scrubbing with a 3M green or red pad or even a stiff brush, will probably give best results. Be sure to scrub cross grain or in a circular motion.

Be sure to thoroughly dry and ventilate the area afterwards.

Photos may help.

_________________
Good luck,
Bob Lowe
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:      View previous topic :: View next topic  
Post new topic   Reply to topic    International Association of Grand Banks Owners Forum Index -> Specifications All times are GMT - 5 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum


Copyright ©2006. All Rights Reserved.

Powered by phpBB © 2001, 2005 phpBB Group