Topics

[Amel Yacht Owners] Re: re caulking of stanchion base


James Alton
 

Bill,

  Thanks so much for sharing your project of removing and resealing the stanchion bases and fastenings.  Your reasons for doing this project echo my own and despite limited sailing time due to the Schengen visa limitations, I will be soon removing as many of the stanchion bolts as I can on my own boat and resealing them since I consider this project to be very high on the list.  It is very encouraging to me that you have been able to remove all but one bolt so far,  I suspect you are using a good technique.    Do you know if the bolts on Haramonie might have been removed and resealed before or do you think that they are original?   I am glad to hear that you are replacing all of the bolts with the most corrosion resistant ones that you can find,  money well spent!  May I ask what size bolt and thread count were used on your boat?
    
    I do have one question that has been troubling me regarding this project.  Without a doubt, using a product like Tef-gel will make future removal of the bolts much easier and I want to do the same.  I am however wondering if the Tef-gel will be enough to keep water from working it’s way down the threads, into the holes and eventually corroding the embedded steel?  In an ideal world, perhaps we could have the Tef-Gel only on the area of the bolt that rides on the threads of the embedded steel and a really good sealant to exclude the water on the part of the bolt that passes through the fibreglass.  Carefully applying the Tef-Gel to only the embedded threaded portion and using sealant on the bolt itself is something that I was wondering about.   I am not sure that it would work well since any Tef-gel contamination of the fibreglass surface would probably ruin the sealant bond/seal.  Do you feel that the Tef-Gel will provide an adequate seal on it’s own to keep water from reaching the embedded steel and is this something that you have also pondered?

Best,

James Alton
SV Sueño
Maramu #220

  

  

On Aug 6, 2018, at 4:26 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

Paul,


What a timely question!  I am in the process of doing exactly that. I have an impact wrench with a flat blade screwdriver bit that has been the only way most of these bolts come out.  It is VITAL that the bit fit the screws very closely.

When we bought Harmonie we were told that pulling these screws and re-seating them after treating with Tef-Gel should be a once in ten-year project on any Amel.  If it is done often it is easy.  If not... it is a miserable project.

Rust at the base of the stanchions can come from three sources.

On Harmonie there is no bedding compound between the flat part of the stanchion base and the fiberglass gunwale.  This means that there is a fairly large flat area of stainless steel that is mostly excluded from the oxygen in the air that protects it from corrosion, but where water can creep in and get rust started.  This is the least critical rust issue. I see it on each of the stanchions I have removed so far, even on those that showed no visible rust stains around them before removal.

The bolts themselves can corrode on the underside of the head.  Again, a place where water can get to, but has limited access to air.  The problem with this is it can significantly weaken the bolt.  I have seen stainless bolts with this kind of corrosion where the head literally fell off.  So far I have found one bolt like this.  The head twisted off when I put torque on it to remove.  I am in the process now of drilling it out for removal. Not my idea of fun.

The last possible source of rust staining is the most serious, and is the real reason for making this a routine maintenance project.  When water finds its way down into the threads of the bolts it begins to corrode the steel plate that Amel set into the fiberglass. The resulting rust irresistibly expands and will destroy the fiberglass around it in a very slow motion explosion. This requires a complex, and expensive repair.

The impact wrench has been successful at removing the bolts so far (except the one that broke!)  After removal the heads are beat up enough that I am replacing them with the most corrosion resistant machine screws I can find--of 316L stainless. 

The rail has a joint about a meter forward of the aft corner.  Once you get the rear two stanchions unbolted, that piece can be removed. (The stanchion all the way back on the transom is through bolted, not in a tapped hole.)

Once you get a few stanchions unbolted, you will have enough "wiggle room" to lift each of the stanchion bases up, clean them up, and get some caulking under them.  Since the stainless screws are going to be threaded into steel backing plates, they should be generously treated with Tef-Gel or whatever  brand of anti-corrosion thread lubricant is your favorite.  Then all will be better for another decade!

Bill Kinney
SM160, Harmonie
Annapolis, MD, USA


 



greatketch@...
 

James,

The bolts on Harmonie are Flat head machine screws, M8-1.25 x 30mm  I see no evidence that they had ever been removed since the boat was built in 1996.

We are very much on the same page with thinking about the issues/concerns in getting those bolts sealed back up.  If you read Joel's notes he does mention adding sealant under the stanchion base in addition to the tef-gel on the threads.  Done properly, that should keep the water away from the steel.

I think the combination is much better than just putting a dab of silicon on the screws as was done on my boat.

Here is my approach:
 
Each bolt hole will have a chamfer cut into the surface of the fiberglass with a countersink bit.

The bolts will have a thin coat of tef-gel added to the bottom couple of threads.  I might just put some down in the bolt hole to minimize contact with the upper threads--for all the reasons you expressed. Another alternative is to apply tef-gel to a screw, insert it all the way in the hole to smear the tef-gel on the female threads, then remove it and use a clean screw for final assembly.

The bottom of the stanchion base will have a layer of butyl sealing tape applied, with a little more wrapped around the bolt at the very top of the threads.

Butyl tape "flows" amazingly well.  Even if the threads of the bolts have a bit of tef-gel on them, I am confident that the butyl flowing into the chamfer I made at the top of the hole will be good enough to keep water out.

This basic technique has worked well for me in the past in similar situations. 

Bill Kinney
SM160, Harmonie
Annapolis, MD, USA


James Alton
 

Bill Kinney,

   I was originally thinking of using a non acid based silicone caulking for  bedding my stanchions but I think that you may have hit on the perfect solution using the Butyl tape to provide the required sealing. The caulking seal would have to rely on a good bond whereas the butyl should produce a good seal simply from compression and chamfering the top of the hole will increase the reliability of a compression seal.   While the butyl might not attach well to the fibreglass if some Tef-Gel is present, it will be well adhered to the inside of the stanchion base so should not try to crawl out.    You can also come back and gently tighten the bolts at a later time with Butyl which would destroy the bond and seal of a caulk.  The Butyl should reseal to the bolt in response the increased compression.  Finally, since these bolts really should be replaced and resealed as a part of a maintenance schedule the butyl is going to be easier to clean up.   I really really like your plan and will be packing some Butyl into my luggage!

   Do the holes tapped into the embedded steel bottom or pass completely through the steel?  I am thinking that if they pass thru that we can afford to be more generous with the Tef-gel since it will not be forced out of the hole to the surface.  If the holes bottom, your idea of using a bolt to apply the Tef Gel to the female threads sounds like an excellent way of applying the optimal amount of product.

   I also sometimes chamfer holes to provide a clean surface for caulking to bond to and I do think that it improves the seal.  I am sure that you will be careful to not cut away too much material but I have seen on a number of boats where the chamfering has extended pretty deep into fibreglass which can be a bad thing structurally since the shear strength is going to be reduced.  

Best,

James 
Maramu #220 

On Aug 6, 2018, at 7:00 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

James,


The bolts on Harmonie are Flat head machine screws, M8-1.25 x 30mm  I see no evidence that they had ever been removed since the boat was built in 1996.

We are very much on the same page with thinking about the issues/concerns in getting those bolts sealed back up.  If you read Joel's notes he does mention adding sealant under the stanchion base in addition to the tef-gel on the threads.  Done properly, that should keep the water away from the steel.

I think the combination is much better than just putting a dab of silicon on the screws as was done on my boat.

Here is my approach:
 
Each bolt hole will have a chamfer cut into the surface of the fiberglass with a countersink bit.

The bolts will have a thin coat of tef-gel added to the bottom couple of threads.  I might just put some down in the bolt hole to minimize contact with the upper threads--for all the reasons you expressed. Another alternative is to apply tef-gel to a screw, insert it all the way in the hole to smear the tef-gel on the female threads, then remove it and use a clean screw for final assembly.

The bottom of the stanchion base will have a layer of butyl sealing tape applied, with a little more wrapped around the bolt at the very top of the threads.

Butyl tape "flows" amazingly well.  Even if the threads of the bolts have a bit of tef-gel on them, I am confident that the butyl flowing into the chamfer I made at the top of the hole will be good enough to keep water out.

This basic technique has worked well for me in the past in similar situations. 

Bill Kinney
SM160, Harmonie
Annapolis, MD, USA



Mark Erdos
 

Bill,

 

Are you using an impact driver? Manual, air or electric?

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff

www.creampuff.us

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Monday, August 6, 2018 7:00 PM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: re caulking of stanchion base

 

 

James,

 

The bolts on Harmonie are Flat head machine screws, M8-1.25 x 30mm  I see no evidence that they had ever been removed since the boat was built in 1996.

 

We are very much on the same page with thinking about the issues/concerns in getting those bolts sealed back up.  If you read Joel's notes he does mention adding sealant under the stanchion base in addition to the tef-gel on the threads.  Done properly, that should keep the water away from the steel.

 

I think the combination is much better than just putting a dab of silicon on the screws as was done on my boat.

 

Here is my approach:

 

Each bolt hole will have a chamfer cut into the surface of the fiberglass with a countersink bit.

 

The bolts will have a thin coat of tef-gel added to the bottom couple of threads.  I might just put some down in the bolt hole to minimize contact with the upper threads--for all the reasons you expressed. Another alternative is to apply tef-gel to a screw, insert it all the way in the hole to smear the tef-gel on the female threads, then remove it and use a clean screw for final assembly.

 

The bottom of the stanchion base will have a layer of butyl sealing tape applied, with a little more wrapped around the bolt at the very top of the threads.

 

Butyl tape "flows" amazingly well.  Even if the threads of the bolts have a bit of tef-gel on them, I am confident that the butyl flowing into the chamfer I made at the top of the hole will be good enough to keep water out.

 

This basic technique has worked well for me in the past in similar situations. 

 

Bill Kinney

SM160, Harmonie

Annapolis, MD, USA


greatketch@...
 

Mark,

An impact driver is one of those tools you don't really need... until you do!

I am using a Ridgid cordless electric 1/2 inch drive impact driver.  If not this exact model, then one just like it. 

Nothing magic about the brand--it just used a battery that matched the drill I already owned.  The 1/2 inch drive makes finding attachments a bit more difficult, but it is a more powerful tool than the typical 1/4 inch snap-in attachments most consumer models use.   

I am sure the typical air drive impact wrench would do at least as well.  

I have tried a couple of the impact wrenches that are powered by manual hammer blows.  I have never found one that I thought was worth anything.

I have a collection of these kinds of bits in different sizes for various screw head sizes.  

For most of the screws a big, square shaft, screw driver that lets you turn it with a wrench will let you get enough torque to get the screws out.  Get the screwdrivers from one of the brands that offers a lifetime warrantee, you'll probably bend or break a few!  

It's really, really, important that when you use this much torque you have a tool that fits the screw really well otherwise you'll just destroy the screw head.

Bill Kinney
SM160, Harmonie
Annapolis, MD, USA








---In amelyachtowners@..., <mcerdos@...> wrote :

Bill,

 

Are you using an impact driver? Manual, air or electric?

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff

www.creampuff.us

  


Mark Erdos
 

Bill,

 

Thanks for the info.

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Bonaire

www.creampuff.us

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, August 7, 2018 6:16 PM
To: amelyachtowners@...
Subject: RE: [Amel Yacht Owners] Re: re caulking of stanchion base

 

 

Mark,

 

An impact driver is one of those tools you don't really need... until you do!

 

I am using a Ridgid cordless electric 1/2 inch drive impact driver.  If not this exact model, then one just like it. 



Nothing magic about the brand--it just used a battery that matched the drill I already owned.  The 1/2 inch drive makes finding attachments a bit more difficult, but it is a more powerful tool than the typical 1/4 inch snap-in attachments most consumer models use.   



I am sure the typical air drive impact wrench would do at least as well.  

 

I have tried a couple of the impact wrenches that are powered by manual hammer blows.  I have never found one that I thought was worth anything.

 

I have a collection of these kinds of bits in different sizes for various screw head sizes.  

 

For most of the screws a big, square shaft, screw driver that lets you turn it with a wrench will let you get enough torque to get the screws out.  Get the screwdrivers from one of the brands that offers a lifetime warrantee, you'll probably bend or break a few!  

 

It's really, really, important that when you use this much torque you have a tool that fits the screw really well otherwise you'll just destroy the screw head.

 

Bill Kinney

SM160, Harmonie

Annapolis, MD, USA

 

 

 

 

 

 



---In amelyachtowners@..., wrote :

Bill,

 

Are you using an impact driver? Manual, air or electric?

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff

www.creampuff.us

  


eric freedman
 

I have personally rebuilt 3 sailboats from the through hulls up.

I Used Duralac on all of them. It is far superior to tefgel as it is much more . It is a paste and not a gel/.

 

Duralac is an anti-corrosive jointing compound for use between joints of dissimilar metals. It is in the form of a tough, flexible, yellow paste with low moisture permeability, and contains barium chromate in an inert filler matrix. The barium chromate is only very slightly soluble in water, so it remains in the joint, even in the presence of a considerable flow of water. It has a long useful life because it only becomes active in the presence of conditions which promote corrosion. 
• Indispensable for the effective sealing of joints between dissimilar metals --- even very active magnesium alloys 
• Effective at preventing corrosion at stress contact points in similar metals, such as rivets in masts 
• Protects metals in contact with non-metallic materials such as wood, resins, rubber, etc. 
• Especially useful in saltwater environments which exacerbate corrosive processes 
• Conforms to specification DTD 369B
.

 

It remains “waterproof “ and has worked well on my newest boat for the last 16 years.

I visited a boat I rebuilt 20 years ago and helped the owner do some maintenance. The bolts with Duralac came out like new.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

https://www.fisheriessupply.com/saddington-consultants-plus-duralac-anti-corrosion-jointing-compound

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Monday, August 06, 2018 5:57 PM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: re caulking of stanchion base

 

 

Bill,

 

  Thanks so much for sharing your project of removing and resealing the stanchion bases and fastenings.  Your reasons for doing this project echo my own and despite limited sailing time due to the Schengen visa limitations, I will be soon removing as many of the stanchion bolts as I can on my own boat and resealing them since I consider this project to be very high on the list.  It is very encouraging to me that you have been able to remove all but one bolt so far,  I suspect you are using a good technique.    Do you know if the bolts on Haramonie might have been removed and resealed before or do you think that they are original?   I am glad to hear that you are replacing all of the bolts with the most corrosion resistant ones that you can find,  money well spent!  May I ask what size bolt and thread count were used on your boat?

    

    I do have one question that has been troubling me regarding this project.  Without a doubt, using a product like Tef-gel will make future removal of the bolts much easier and I want to do the same.  I am however wondering if the Tef-gel will be enough to keep water from working it’s way down the threads, into the holes and eventually corroding the embedded steel?  In an ideal world, perhaps we could have the Tef-Gel only on the area of the bolt that rides on the threads of the embedded steel and a really good sealant to exclude the water on the part of the bolt that passes through the fibreglass.  Carefully applying the Tef-Gel to only the embedded threaded portion and using sealant on the bolt itself is something that I was wondering about.   I am not sure that it would work well since any Tef-gel contamination of the fibreglass surface would probably ruin the sealant bond/seal.  Do you feel that the Tef-Gel will provide an adequate seal on it’s own to keep water from reaching the embedded steel and is this something that you have also pondered?

 

Best,

 

James Alton

SV Sueño

Maramu #220

 

  

 

  

On Aug 6, 2018, at 4:26 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Paul,

 

What a timely question!  I am in the process of doing exactly that. I have an impact wrench with a flat blade screwdriver bit that has been the only way most of these bolts come out.  It is VITAL that the bit fit the screws very closely.

 

When we bought Harmonie we were told that pulling these screws and re-seating them after treating with Tef-Gel should be a once in ten-year project on any Amel.  If it is done often it is easy.  If not... it is a miserable project.

 

Rust at the base of the stanchions can come from three sources.

 

On Harmonie there is no bedding compound between the flat part of the stanchion base and the fiberglass gunwale.  This means that there is a fairly large flat area of stainless steel that is mostly excluded from the oxygen in the air that protects it from corrosion, but where water can creep in and get rust started.  This is the least critical rust issue. I see it on each of the stanchions I have removed so far, even on those that showed no visible rust stains around them before removal.

 

The bolts themselves can corrode on the underside of the head.  Again, a place where water can get to, but has limited access to air.  The problem with this is it can significantly weaken the bolt.  I have seen stainless bolts with this kind of corrosion where the head literally fell off.  So far I have found one bolt like this.  The head twisted off when I put torque on it to remove.  I am in the process now of drilling it out for removal. Not my idea of fun.

 

The last possible source of rust staining is the most serious, and is the real reason for making this a routine maintenance project.  When water finds its way down into the threads of the bolts it begins to corrode the steel plate that Amel set into the fiberglass. The resulting rust irresistibly expands and will destroy the fiberglass around it in a very slow motion explosion. This requires a complex, and expensive repair.

 

The impact wrench has been successful at removing the bolts so far (except the one that broke!)  After removal the heads are beat up enough that I am replacing them with the most corrosion resistant machine screws I can find--of 316L stainless. 

 

The rail has a joint about a meter forward of the aft corner.  Once you get the rear two stanchions unbolted, that piece can be removed. (The stanchion all the way back on the transom is through bolted, not in a tapped hole.)

 

Once you get a few stanchions unbolted, you will have enough "wiggle room" to lift each of the stanchion bases up, clean them up, and get some caulking under them.  Since the stainless screws are going to be threaded into steel backing plates, they should be generously treated with Tef-Gel or whatever  brand of anti-corrosion thread lubricant is your favorite.  Then all will be better for another decade!



Bill Kinney

SM160, Harmonie

Annapolis, MD, USA





 

 

 


James Cromie
 

How would you compare this to Never Seez.  They are very different materials with different purposes, and I would want to know when one would use one or the other of these antiseize / anti-corrosion compounds.  

James

On Aug 8, 2018, at 10:14 PM, 'sailormon' kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:


I have personally rebuilt 3 sailboats from the through hulls up.

I Used Duralac on all of them. It is far superior to tefgel as it is much more . It is a paste and not a gel/..

 

Duralac is an anti-corrosive jointing compound for use between joints of dissimilar metals.. It is in the form of a tough, flexible, yellow paste with low moisture permeability, and contains barium chromate in an inert filler matrix. The barium chromate is only very slightly soluble in water, so it remains in the joint, even in the presence of a considerable flow of water. It has a long useful life because it only becomes active in the presence of conditions which promote corrosion. 
• Indispensable for the effective sealing of joints between dissimilar metals --- even very active magnesium alloys 
• Effective at preventing corrosion at stress contact points in similar metals, such as rivets in masts 
• Protects metals in contact with non-metallic materials such as wood, resins, rubber, etc. 
• Especially useful in saltwater environments which exacerbate corrosive processes 
• Conforms to specification DTD 369B
.

 

It remains “waterproof “ and has worked well on my newest boat for the last 16 years.

I visited a boat I rebuilt 20 years ago and helped the owner do some maintenance. The bolts with Duralac came out like new.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

https://www.fisheriessupply.com/saddington-consultants-plus-duralac-anti-corrosion-jointing-compound

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...] 
Sent: Monday, August 06, 2018 5:57 PM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: re caulking of stanchion base

 

  

Bill,

 

  Thanks so much for sharing your project of removing and resealing the stanchion bases and fastenings.  Your reasons for doing this project echo my own and despite limited sailing time due to the Schengen visa limitations, I will be soon removing as many of the stanchion bolts as I can on my own boat and resealing them since I consider this project to be very high on the list.  It is very encouraging to me that you have been able to remove all but one bolt so far,  I suspect you are using a good technique.    Do you know if the bolts on Haramonie might have been removed and resealed before or do you think that they are original?   I am glad to hear that you are replacing all of the bolts with the most corrosion resistant ones that you can find,  money well spent!  May I ask what size bolt and thread count were used on your boat?

    

    I do have one question that has been troubling me regarding this project.  Without a doubt, using a product like Tef-gel will make future removal of the bolts much easier and I want to do the same.  I am however wondering if the Tef-gel will be enough to keep water from working it’s way down the threads, into the holes and eventually corroding the embedded steel?  In an ideal world, perhaps we could have the Tef-Gel only on the area of the bolt that rides on the threads of the embedded steel and a really good sealant to exclude the water on the part of the bolt that passes through the fibreglass.  Carefully applying the Tef-Gel to only the embedded threaded portion and using sealant on the bolt itself is something that I was wondering about.   I am not sure that it would work well since any Tef-gel contamination of the fibreglass surface would probably ruin the sealant bond/seal.  Do you feel that the Tef-Gel will provide an adequate seal on it’s own to keep water from reaching the embedded steel and is this something that you have also pondered?

 

Best,

 

James Alton

SV Sueño

Maramu #220

 

  

 

  

On Aug 6, 2018, at 4:26 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Paul,

 

What a timely question!  I am in the process of doing exactly that. I have an impact wrench with a flat blade screwdriver bit that has been the only way most of these bolts come out.  It is VITAL that the bit fit the screws very closely.

 

When we bought Harmonie we were told that pulling these screws and re-seating them after treating with Tef-Gel should be a once in ten-year project on any Amel.  If it is done often it is easy..  If not... it is a miserable project.

 

Rust at the base of the stanchions can come from three sources.

 

On Harmonie there is no bedding compound between the flat part of the stanchion base and the fiberglass gunwale.  This means that there is a fairly large flat area of stainless steel that is mostly excluded from the oxygen in the air that protects it from corrosion, but where water can creep in and get rust started.  This is the least critical rust issue. I see it on each of the stanchions I have removed so far, even on those that showed no visible rust stains around them before removal.

 

The bolts themselves can corrode on the underside of the head.  Again, a place where water can get to, but has limited access to air.  The problem with this is it can significantly weaken the bolt.  I have seen stainless bolts with this kind of corrosion where the head literally fell off.  So far I have found one bolt like this.  The head twisted off when I put torque on it to remove.  I am in the process now of drilling it out for removal.. Not my idea of fun.

 

The last possible source of rust staining is the most serious, and is the real reason for making this a routine maintenance project.  When water finds its way down into the threads of the bolts it begins to corrode the steel plate that Amel set into the fiberglass. The resulting rust irresistibly expands and will destroy the fiberglass around it in a very slow motion explosion. This requires a complex, and expensive repair.

 

The impact wrench has been successful at removing the bolts so far (except the one that broke!)  After removal the heads are beat up enough that I am replacing them with the most corrosion resistant machine screws I can find--of 316L stainless. 

 

The rail has a joint about a meter forward of the aft corner.  Once you get the rear two stanchions unbolted, that piece can be removed. (The stanchion all the way back on the transom is through bolted, not in a tapped hole.)

 

Once you get a few stanchions unbolted, you will have enough "wiggle room" to lift each of the stanchion bases up, clean them up, and get some caulking under them.  Since the stainless screws are going to be threaded into steel backing plates, they should be generously treated with Tef-Gel or whatever  brand of anti-corrosion thread lubricant is your favorite.  Then all will be better for another decade!



Bill Kinney

SM160, Harmonie

Annapolis, MD, USA





 

 

 




eric freedman
 

I use never seize only on the shaft for the mainsail outhaul. I grease it every 6 months. Never seize is more like an anti- corrosive. It is advertised as a lubricant. I believe they also say it decreases galvanic corrosion. However after using Duralac for so many years I am sold on it.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Wednesday, August 08, 2018 10:41 PM
To: isaac_02906@... [amelyachtowners]
Subject: Re: [Amel Yacht Owners] Re: re caulking of stanchion base

 

 

How would you compare this to Never Seez.  They are very different materials with different purposes, and I would want to know when one would use one or the other of these antiseize / anti-corrosion compounds.  

 

James

On Aug 8, 2018, at 10:14 PM, 'sailormon' kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

I have personally rebuilt 3 sailboats from the through hulls up.

I Used Duralac on all of them. It is far superior to tefgel as it is much more . It is a paste and not a gel/..

 

Duralac is an anti-corrosive jointing compound for use between joints of dissimilar metals.. It is in the form of a tough, flexible, yellow paste with low moisture permeability, and contains barium chromate in an inert filler matrix. The barium chromate is only very slightly soluble in water, so it remains in the joint, even in the presence of a considerable flow of water. It has a long useful life because it only becomes active in the presence of conditions which promote corrosion. 
• Indispensable for the effective sealing of joints between dissimilar metals --- even very active magnesium alloys 
• Effective at preventing corrosion at stress contact points in similar metals, such as rivets in masts 
• Protects metals in contact with non-metallic materials such as wood, resins, rubber, etc. 
• Especially useful in saltwater environments which exacerbate corrosive processes 
• Conforms to specification DTD 369B
.

 

It remains “waterproof “ and has worked well on my newest boat for the last 16 years.

I visited a boat I rebuilt 20 years ago and helped the owner do some maintenance. The bolts with Duralac came out like new.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

https://www.fisheriessupply.com/saddington-consultants-plus-duralac-anti-corrosion-jointing-compound

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...] 
Sent: Monday, August 06, 2018 5:57 PM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: re caulking of stanchion base

 

  

Bill,

 

  Thanks so much for sharing your project of removing and resealing the stanchion bases and fastenings.  Your reasons for doing this project echo my own and despite limited sailing time due to the Schengen visa limitations, I will be soon removing as many of the stanchion bolts as I can on my own boat and resealing them since I consider this project to be very high on the list.  It is very encouraging to me that you have been able to remove all but one bolt so far,  I suspect you are using a good technique.    Do you know if the bolts on Haramonie might have been removed and resealed before or do you think that they are original?   I am glad to hear that you are replacing all of the bolts with the most corrosion resistant ones that you can find,  money well spent!  May I ask what size bolt and thread count were used on your boat?

    

    I do have one question that has been troubling me regarding this project.  Without a doubt, using a product like Tef-gel will make future removal of the bolts much easier and I want to do the same.  I am however wondering if the Tef-gel will be enough to keep water from working it’s way down the threads, into the holes and eventually corroding the embedded steel?  In an ideal world, perhaps we could have the Tef-Gel only on the area of the bolt that rides on the threads of the embedded steel and a really good sealant to exclude the water on the part of the bolt that passes through the fibreglass.  Carefully applying the Tef-Gel to only the embedded threaded portion and using sealant on the bolt itself is something that I was wondering about.   I am not sure that it would work well since any Tef-gel contamination of the fibreglass surface would probably ruin the sealant bond/seal.  Do you feel that the Tef-Gel will provide an adequate seal on it’s own to keep water from reaching the embedded steel and is this something that you have also pondered?

 

Best,

 

James Alton

SV Sueño

Maramu #220

 

  

 

  

On Aug 6, 2018, at 4:26 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Paul,

 

What a timely question!  I am in the process of doing exactly that. I have an impact wrench with a flat blade screwdriver bit that has been the only way most of these bolts come out.  It is VITAL that the bit fit the screws very closely.

 

When we bought Harmonie we were told that pulling these screws and re-seating them after treating with Tef-Gel should be a once in ten-year project on any Amel.  If it is done often it is easy..  If not... it is a miserable project.

 

Rust at the base of the stanchions can come from three sources.

 

On Harmonie there is no bedding compound between the flat part of the stanchion base and the fiberglass gunwale.  This means that there is a fairly large flat area of stainless steel that is mostly excluded from the oxygen in the air that protects it from corrosion, but where water can creep in and get rust started.  This is the least critical rust issue. I see it on each of the stanchions I have removed so far, even on those that showed no visible rust stains around them before removal.

 

The bolts themselves can corrode on the underside of the head.  Again, a place where water can get to, but has limited access to air.  The problem with this is it can significantly weaken the bolt.  I have seen stainless bolts with this kind of corrosion where the head literally fell off.  So far I have found one bolt like this.  The head twisted off when I put torque on it to remove.  I am in the process now of drilling it out for removal.. Not my idea of fun.

 

The last possible source of rust staining is the most serious, and is the real reason for making this a routine maintenance project.  When water finds its way down into the threads of the bolts it begins to corrode the steel plate that Amel set into the fiberglass. The resulting rust irresistibly expands and will destroy the fiberglass around it in a very slow motion explosion. This requires a complex, and expensive repair.

 

The impact wrench has been successful at removing the bolts so far (except the one that broke!)  After removal the heads are beat up enough that I am replacing them with the most corrosion resistant machine screws I can find--of 316L stainless. 

 

The rail has a joint about a meter forward of the aft corner.  Once you get the rear two stanchions unbolted, that piece can be removed. (The stanchion all the way back on the transom is through bolted, not in a tapped hole.)

 

Once you get a few stanchions unbolted, you will have enough "wiggle room" to lift each of the stanchion bases up, clean them up, and get some caulking under them.  Since the stainless screws are going to be threaded into steel backing plates, they should be generously treated with Tef-Gel or whatever  brand of anti-corrosion thread lubricant is your favorite.  Then all will be better for another decade!




Bill Kinney

SM160, Harmonie

Annapolis, MD, USA