Quintrex - 12 Month Inspection

[Fab1]

Thank guys,

So, the oxidising under the stainless fitting is due to disimilar metals in contact with each other without the protection of duralac

and the oxidisation around the transom rubber may be due to poor painting preparation in the first place.

More than likely, but don't kid yourself that by using duralac, gaskets, etc, you will never get corrosion again.

Stay with me:

Here's why-

Say your aluminium boat is built with all it's holes pre drilled/punched ready for fixtures once the painting is complete.

Then it gets cleaned, etch primed, primed, painted and set to bake in the booth to cure.

You now inspect the boats EXTERIOR paint finish that has just been completed and all looks good.

I can tell you now the paint on the FLAT horizontal surfaces will be way thicker than the paint on the FLAT vertical surfaces.

And the FLAT vertical surfaces the paint will be thicker than on the corners of panels.

And the CORNERS of panels will have thicker paint than the rim of mounting holes.

It's all due to gravity amongst other things.

Now that we know that the rim of the fasteners hole has the least paint.

When you put your hardware in place and screw/bolt your fastener in.

The threads from the fastener remove (breach)that very thin film of paint from the circumference of the hole exposing the bare alloy.

Pop rivets will do the same but are less severe as they are smoother than a threaded fastener obviously.

Once the salt laden air/water get behind the fittings it will work it's way into the bare aluminium buy working its way underneath the paint and start the corrosion process.

Using duralac and other products the same thing happens, once you secure your fittings you compromise the seal.

Using gaskets inbetween the alloy and the fitting the fitting and alloy are in effect seperated by the gasket but both remain in contact by the fasteners themselves that have breached that rim of that little hole when the fasteners were secured down.

You mention that you wash and dry your boat thoroughly.

Washing and drying your boat won't do anything unfortunately to prevent this,as im sure you will agree after having read the above.

I've tried to explain above to help you and others that may be unaware what causes these issues.

It's just the way it is owning a painted aluminium boat, among other reasons why I have an unpainted boat.

Hopefully this has helped clarify some of the causes of this issue.

If you need advice how to repair pm me and i'll gladly help you out.

Cheers.

I have to say here that there are lots of other fittings on the boat whch I susepect would be more likely to be exposed to salt water but they have remained unblemished.

I noticed these issues months ago and they have not gotten any worse.

I always wash and dry the boat thorougly after use.

All boat brand selection and loyalties aside my objectives here are;

1) to establish whether any of this can be put back on to Telwater

2) to understand what causes the corrosion.

3) to fix it using the best practices possible.

I would have no hesitation in removing every fitting in the boat and either aunimium rivetting it back on or using duralac as protection.

To that end you guys are being very helpful so keep it coming.

Cheers

Jim

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[Paikea]

I have seen corrosion of the area around and on the welds of welded on cleats on a number of Quinies and wonder if the is due to the welding filler rod being used not matching the hull/cleat material. The bubbling was quite extensive and very ugly.

Anyone have any views on this?

Cheers

Paikea

[Billy2014]

I have seen corrosion of the area around and on the welds of welded on cleats on a number of Quinies and wonder if the is due to the welding filler rod being used not matching the hull/cleat material. The bubbling was quite extensive and very ugly.

Anyone have any views on this?

Cheers

Paikea

You can normally weld hull material which is most likely 5052 on the Quinie with cast aluminum fittings using 5356 filler, this shouldn't corrode unless there was a fair bit of porosity in the original weld which is possible because cast fittings are a bit like aero bars sometimes, full of air pockets inside which can contaminate the weld if not dealt with correctly. Cast fittings aren't great, they tend to break a lot buts that's another subject.

Edited July 16, 2014 by Billy2014

[Fab1]

You can normally weld hull material which is most likely 5052 on the Quinie with cast aluminum fittings using 5356 filler, this shouldn't corrode unless there was a fair bit of porosity in the original weld which is possible because cast fittings are a bit like aero bars sometimes, full of air pockets inside which can contaminate the weld if not dealt with correctly. Cast fittings aren't great, they tend to break a lot buts that's another subject.

Totally agree mate.

Paikea,the problem with painted welded cleats is that the paint will eventually wear through the cleats legs from constant rubbing/chaffing from ropes which can also allow saltwater moisture to get under the paint starting corrosion.

As mentioned above any porosity/pinholes in welds,chips/scratches in paint etc, saltwater is very good at finding it's way in leading to the same thing occuring.

And don't think it occurs with quintrex only, it can happen with any painted aluminium boat regardless of brand/price.

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[fragmeister]

Thanks to all for all the advice and comments.

Clearly there is a lot of experience on this forum and it has certainly pointed me in the right direction.

I have contacted my dealer and I will see how they repsond.

I will post the reponses I get along the way

Thanks

Jim

[fragmeister]

Hi Guys,

Here is an update.

I contacted my dealer and the offered to take a look with a view to repairing the paintwork.

They also said that it not likely to be a case of severe corrosion but merely the result of impurities in the aluminium used in boat production today.

This happens on most boats and it is not the start of massive aluminium cancer.

Restrictions on the additives allowed in paints today are also an issue.

At this stage they are doing the right thing so I will keep you all posted.

Cheers

Jim

I

[fragmeister]

So,

I took the boat back and dealer still maintained it was a waste of time taking this issue to Telwater.

Having said that they offered to get their spray painter in to fix the issues with the paint at no charge as a gesture of good will.

This is now in the process of getting done and of course I am happy with that.

I did my research, politely suggested that the two areas of concern were likely to be inadequate preparation or inadequate separation of dissimilar metals,

reminded them of the significant investment and they did the right thing.

These seem to be the only spots which have a problem so I'll let you all know at the next 12 months inspection.

Thank you all again for contributing information to this post and assisting me get a good outcome.

Cheers

Jim

[Paikea]

I insulated all stainless screws in my Trailcraft using nylon stepped washers. Never had any corrosion.

The details were set out in my post titled; Corrosion in Ally boats. If you really want to do everything possible to prevent corrosion have a look at that post. Just enter the Title in the search box at the RH top of this page and click the green box.

appreciate any comments.

Cheers

Paikea

[fragmeister]

Thanks Paikea,

I think I have already seen that post and it has a lot of good info.

Cheers

Jim

[Dfishin]

Jim

Keep on top of it.

I dont know heaps about this matter. There are posts on here that suggest not to worry about this matter. I do know this. I had a STACER whith all these signs. Electrolysis, Dissimilar metals, Electronics earthed to Alloy Hull Whatever you want to call it. After a few years started leaking, Pin holes in the hull below the water line started to appear and kept appearing most of them coming from large piting in the alloy from under the floor many under struts of the boat. Tried everything to stop it obviously found out about all the previous mentiond matters when we started searching for answers, tried more zinc blocks bolted to hull under the floor and couldnt stop it.

Just saying it is an issue.

Dave

[fragmeister]

Jim

Keep on top of it.

I dont know heaps about this matter. There are posts on here that suggest not to worry about this matter. I do know this. I had a STACER whith all these signs. Electrolysis, Dissimilar metals, Electronics earthed to Alloy Hull Whatever you want to call it. After a few years started leaking, Pin holes in the hull below the water line started to appear and kept appearing most of them coming from large piting in the alloy from under the floor many under struts of the boat. Tried everything to stop it obviously found out about all the previous mentiond matters when we started searching for answers, tried more zinc blocks bolted to hull under the floor and couldnt stop it.

Just saying it is an issue.

Dave

Thanks Dave,

I did the full inspection at 12 months and it seems like its just around a few stainless fittings.

I will certainly look carefully at any sign if an issue and conduct another complete inspection at 12 months.

Cheers & thanks for the reminder to be diligent.

Jim