Aluminium Hull

[neil.mccrirrick]

Hi All,

I have an aluminium hull. The photos are of the stern and the port side, all the hull is pretty much like this though.

From what I understand none of this will cause a problem, (please say if that's wrong) its just untidy. Getting rid of all the paint etc and going back to bare aluminium may be the best bet.

So questions:

If its just cosmetic is it worth doing, (I know that's a personal choice but I'm undecided so views would be good, especially as once in the water most of this is hidden).

Can I get this off all with nitromors or something like that

would it be better to simply take it somewhere and have it done professionally and if so any ideas on cost?

Thanks

Neil

[GordyP]

Try getting some quotes from the soda blasting guys, leaves a nice slightly matt finish.

To give you an idea, had the underside of a 33ft yacht stripped of years worth of anti-foul for about £300.

[neil.mccrirrick]

Well had a go with a wire brush and an angle grinder and got as far as this

Took 2 hours to get that far and it's a very messy job

So soda blast is the way forward, gone in this weekend to be done. I'll post pics of the finished job fingers crossed all will be good

Sent from my iPad using Rib.net

[hadd]

Originally Posted by neil.mccrirrick

Well had a go with a wire brush and an angle grinder and got as far as this

Took 2 hours to get that far and it's a very messy job

So soda blast is the way forward, gone in this weekend to be done. I'll post pics of the finished job fingers crossed all will be good

Sent from my iPad using Rib.net

I saw the guy working on the hull today Neil its looking great mate

[neil.mccrirrick]

All done and I have to say really pleased with how this has come out. Top job

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[kerny]

Nice job there Neil.

[neil.mccrirrick]

Couple more

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[mick]

Looks great Neil was it the same guy that did HP

[neil.mccrirrick]

What cleaned him up lol .


Don't think so, this guy is based in audenshaw just outside Ashton under Lyme.

[kerny]

Originally Posted by neil.mccrirrick

What cleaned him up lol .

Don't think so, this guy is based in audenshaw just outside Ashton under Lyme.

I didn't know Audenshaw was in the Midlands Neil.

[Dan Gurney]

Looks tidy Neil. All you need now is to slap a nice coat of orange paint on it!

[Rokraider]

Have they sprayed an etch primer or anything on it immeadiatly after the blasting? You don't want bare aluminium exposed to the air for long.

[HUMBER P4VWL]

Looks tidy Neil, you going to paint it now or can you leave it as is? Does it need treating?

[jyasaki]

Originally Posted by Rokraider

Have they sprayed an etch primer or anything on it immeadiatly after the blasting? You don't want bare aluminium exposed to the air for long.

Depends on the alloy. My RIB is 5200 series aluminum, untreated.

If you want the ultimate bling, have it cleaned (acid etched) and Alodyned; end result will be a nice gold color.

jky

[neil.mccrirrick]

It's is ready for paint. But my plan was not to paint. I am under the impression that the ally will oxidise and finish up looking pretty much like a trailer does. Is this not the case?

[captnjack]

Originally Posted by neil.mccrirrick

It's is ready for paint. But my plan was not to paint. I am under the impression that the ally will oxidise and finish up looking pretty much like a trailer does. Is this not the case?

Its already oxidized, pretty much happens immediately. The bottom will stay looking basically as is due if used but stored dry on a trailer. I'd still have a nice big zinc on the transom somewhere to address any stray currents while its in the water or at a marina.

The topsides, if left unpainted, will get a little more corroded looking. Mostly just a visible blotchiness. There's no water flowing over them as a 'polish'. You can wax the topsides if you want, it will minimize the blotchy look. Wax will need to be renewed often but at least its not peeling paint.

[neil.mccrirrick]

Brill thanks. There are two mahoodsive zincs on the transom for just that problem so away we go. Good news

[Rokraider]

Personally, I would find out which grade of aluminium it is made from? Then see if you can get away with it unpainted.

[jyasaki]

Neil;

"Ready for paint" implies the surface has been etched (paint doesn't stick too well to oxidized aluminum, which occurs pretty quickly after cleaning the surface - generally considered within the first hour or so.) The zinc chromate primers most people use as an undercoat etch the surface as they cure (I think.) Otherwise, an acid prep is used.

I assume you're talking cleaned, and stripped of all old paint.

As Jack said, normal oxidation turns the shiny aluminum surface a light-to-medium gray, with a chalky look and feel. Generally that's about as far as it goes, unless some other factor comes into play (dissimilar metal corrosion, electrolysis, etc.)

On my boat, the deck and console show that chalkiness, but the hull itself is still fairly bright. The top of the motor pod (which doesn't see a whole lot of water flow) is also still pretty bright. Can't really explain the latter part.

jky

[neil.mccrirrick]

Top description that's just how it looks. In fact so chalky you think touching it will get dust on your hand. I have to say I quite like the finish. It looks better than the camera shows it

I need a sea trial now to see what effect the salty stuff does. Plus I'm a tad curious if getting all the old paint off will streamline so better fuel and faster top end.

Menai straits next weekend for the sea trail it is mind you Ive passengers this time so that's not going to help with a comparison