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Default Galvanic corrosion

On Thursday, May 15, 2014 11:45:06 AM UTC-4, Wayne. B wrote:
On Thu, 15 May 2014 05:00:06 -0700 (PDT), True North

wrote:



My new boat started to develop blisters under the gunnel paint where the cover snaps are attached.


After the 2nd season of use, I brought this to the attention of the dealer and Legend boats up in Ontario.


This was last October and the manufacturer still hasn't come up with a plan to remedy the problem.


I did the usual Google research and sent the links to the service manager at my dealer.




Guy at Legend said he didn't want to talk directly with me and problem should be handled through dealer.


They also wanted me to tow the boat back to the dealer ( 180 miles round trip ) so techs could check for stray current, which I did while down anyway for winter servicing. No stray current from my motor.


They also suggested that it could be a stray current problem at the docks I frequent or stray current at local, marinas.


I explained that most of the small boat launches I use have no electrical services and anyway, I'm only there long enough to get my trailer and retrieve the boat.


Anyway I just contacted the General Manager of the dealership (member of family who owns the business) who acted as my salesman two years ago when I showed up while the sales staff were away at a boat show.


He says he will look into problem.




From what I read, we have to remove the snaps that screw directly into the painted aluminum gunnel, sand, prime and paint affected areas.


Then we have to find a suitable gasket or washer to isolate the snap and the aluminum and even coat the shafts of the attaching screw with liquid electrical tape or silicone to isolate them as possible.




My question is, can those self tapping screws be backed out of the aluminum and then be re-installed?


I broke two bits trying with a hand screwdriver last fall, so I google up higher rated impact type bits like the Makita Gold


That should hold up in my corded drill/driver.


Anyone ever attempt this.




===



This is a big problem with aluminum sailboat masts and booms where

stainless steel screws and machine screws are used to attach fittings.

I once asked a professional rigger what he recommended and he said

that he always beds the hardware and threads with silicone sealant

before fastening. The silicone creates a thin insulating barrier

between the two metals and prevents corrosion. I've removd hardware

installed that way more than 5 years ago with no problems.




I'm doubtful that anything actually prevents the two metals from connecting.. I suggest you try a simple ohm meter test to prove that to yourself. Rather the silicon is reducing the moisture reaching the joint. If you can keep the water out you will greatly reduce the corrosion. Personally I use teflon thread sealer on everything threaded. It too will help keep the water out as well as lubricate the threads. Stainless is the best hardware since aluminum fasteners would generally be too weak.
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Default Galvanic corrosion

On Thu, 15 May 2014 11:59:49 -0700 (PDT), wrote:

On Thursday, May 15, 2014 11:45:06 AM UTC-4, Wayne. B wrote:
On Thu, 15 May 2014 05:00:06 -0700 (PDT), True North

wrote:



My new boat started to develop blisters under the gunnel paint where the cover snaps are attached.


After the 2nd season of use, I brought this to the attention of the dealer and Legend boats up in Ontario.


This was last October and the manufacturer still hasn't come up with a plan to remedy the problem.


I did the usual Google research and sent the links to the service manager at my dealer.




Guy at Legend said he didn't want to talk directly with me and problem should be handled through dealer.


They also wanted me to tow the boat back to the dealer ( 180 miles round trip ) so techs could check for stray current, which I did while down anyway for winter servicing. No stray current from my motor.


They also suggested that it could be a stray current problem at the docks I frequent or stray current at local, marinas.


I explained that most of the small boat launches I use have no electrical services and anyway, I'm only there long enough to get my trailer and retrieve the boat.


Anyway I just contacted the General Manager of the dealership (member of family who owns the business) who acted as my salesman two years ago when I showed up while the sales staff were away at a boat show.


He says he will look into problem.




From what I read, we have to remove the snaps that screw directly into the painted aluminum gunnel, sand, prime and paint affected areas.


Then we have to find a suitable gasket or washer to isolate the snap and the aluminum and even coat the shafts of the attaching screw with liquid electrical tape or silicone to isolate them as possible.




My question is, can those self tapping screws be backed out of the aluminum and then be re-installed?


I broke two bits trying with a hand screwdriver last fall, so I google up higher rated impact type bits like the Makita Gold


That should hold up in my corded drill/driver.


Anyone ever attempt this.




===



This is a big problem with aluminum sailboat masts and booms where

stainless steel screws and machine screws are used to attach fittings.

I once asked a professional rigger what he recommended and he said

that he always beds the hardware and threads with silicone sealant

before fastening. The silicone creates a thin insulating barrier

between the two metals and prevents corrosion. I've removd hardware

installed that way more than 5 years ago with no problems.




I'm doubtful that anything actually prevents the two metals from connecting.
I suggest you try a simple ohm meter test to prove that to yourself. Rather
the silicon is reducing the moisture reaching the joint. If you can keep the water
out you will greatly reduce the corrosion. Personally I use teflon thread sealer on
everything threaded. It too will help keep the water out as well as lubricate the
threads. Stainless is the best hardware since aluminum fasteners would generally be too weak.


===

Although the exact protection mechanism may be debatable, it has been
well proven that anything that prevents direct contact between
dissimilar metals helps to prevent corrosion.
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Default Galvanic corrosion

On Friday, May 16, 2014 10:30:05 AM UTC-4, wrote:

The first thing Don has to do is be sure these are really stainless

and not chrome over brass.


He's TOO ****ING STUPID TO TELL THE DIFFERENCE.
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Default Galvanic corrosion

Yesterday I was on the Legend website where they have a chat function.
I asked the rep about the snaps and she confirmed that they were indeed stainless steel.
She then asked if I had any other concerns.
I felt chatty so I informed her about the corrosion problem... not really expecting to much back.
She went right to the warranty manager and quoted him as saying salt water corrosion was an unpredictable process and not really a warranty problem. He also stated they didn't recommend their boats be used in salt water.
First I heard of this and no where have I seen this in writing nor did the dealer mention it.
They did say to forward pictures of the blisters and they would consult with the dealer on what to do.
Looks like I may be looking for a good Jewish lawyer.


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Default Galvanic corrosion

On 5/17/2014 6:33 AM, True North wrote:
Yesterday I was on the Legend website where they have a chat function.
I asked the rep about the snaps and she confirmed that they were indeed stainless steel.
She then asked if I had any other concerns.
I felt chatty so I informed her about the corrosion problem... not really expecting to much back.
She went right to the warranty manager and quoted him as saying salt water corrosion was an unpredictable process and not really a warranty problem. He also stated they didn't recommend their boats be used in salt water.
First I heard of this and no where have I seen this in writing nor did the dealer mention it.
They did say to forward pictures of the blisters and they would consult with the dealer on what to do.
Looks like I may be looking for a good Jewish lawyer.

A good Jewish lawyer wouldn't take your case. If you want to prevent
further disintegration of your boat, don't use it in salt water. Do you
know what the third least noble metal next to lead and magnesium is?
Hint. It's one of the materials that Mercury Marine recommends as a
sacrificial anode.
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Default Galvanic corrosion

Jimmy boy... over the last two seasons I've used the boat 80 percent of the time in salt or brackish water.
I don't expect that to change much.
I have the wrong boat and have to figure how to get into a similar fiberglass version without draining my somewhat limited resources.
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On 5/17/2014 7:11 AM, True North wrote:
Jimmy boy... over the last two seasons I've used the boat 80 percent of the time in salt or brackish water.
I don't expect that to change much.
I have the wrong boat and have to figure how to get into a similar fiberglass version without draining my somewhat limited resources.


That might be tough. A savvy used aluminum boat buyer isn't going to be
looking for a pristine buy in a seaport city. Your best bet is to put it
on consignment at an inland dealer. It's too bad you ignored our advice
about aluminum boats in sal****er use. But that's water over the dam.
Let's move on. How can we help you make a better choice this time?
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Default Galvanic corrosion

On 5/17/2014 7:11 AM, True North wrote:
Jimmy boy... over the last two seasons I've used the boat 80 percent of the time in salt or brackish water.
I don't expect that to change much.
I have the wrong boat and have to figure how to get into a similar fiberglass version without draining my somewhat limited resources.



There are many aluminum boats that survive salt water use. The USCG uses
them.

They just have to be designed properly using proper materials and
anti-corrosion precautions.
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Default Galvanic corrosion

True North wrote:
Jimmy boy... over the last two seasons I've used the boat 80 percent of the time in salt or brackish water.
I don't expect that to change much.
I have the wrong boat and have to figure how to get into a similar fiberglass version without draining my somewhat limited resources.

That makes buying a Blackberry Playbook a minor ****up, eh?


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