Naked aluminum

Sail in fresh water! <img src=

alt=

/>

Well, lots of keelboats have non-anodized masts and they seem to hold up for a good while.

You could take it to a local machinist to see if they know where to get it anodized.

Paint might be an option...but it will flake off overtime.

It's generally pretty easy and cheap to get anodising done. But if there is any welding on the part, don't expect a good looking finish around the welds, the rest should be fine though.

I would avoid painting unless you do it with a complete paint system from grind, acid wash, etch primer, undercoat then top coat.

I would check to see if they even fit before you do anything with them. Just my thoughts after seeing what others have delt with from Mystere. Suprising to hear they are making boats again.

Lee

its not the same company.. and so far.. i am not impressed with the new company... but i do love my cat!

i checked them and they fit. they are VERY snug on getting on the rudder. At first i thought they wouldn't fit, and was worried i would break them trying... but they seem ok.

I was considering the http://www.zerorust.com/ mentioned on the

painting my trailer

thread. but not sure

I know there are companies that do dip anodizing in central Florida - it has been years since I needed it, but I'll try to do some digging. There was a time that a certain yellow Nacra 20 had some parts, including a custom spinnaker pole, specially prepared for a certain long-distance off-shore race. Once you have your junk dipped, you can Relax.

Wow, how prolific .... Words to live by!

Thanks for your help. and info is appreciated

Many years ago I brought a Cobra (like a 16ft mossie) After 15 mins of sailing we snapped the mast. The new mast was not anodised. So I got a tube of metal polish and polished it from top to bottom! Took a while, went over it a few times and it looked a lot like a chrome finish.

Caught up with the boat recently, (mast was replaced in 1993) while most of the boat looks pretty delapidated the mast is still shiney and shows no signs of corrosion.

cost about $10 and a couple hours of elbow greese.

HTH

Anodizing can be and is done in about every major metropolitan area in the world. As suggested, call a Machine or Sheet metal shop, they'll know where to send you. Etch and a dip should be pretty cheap. (hmmm...Wouter must be sleeping)

Alu, that is not anodised will hold up pretty well fro quite a long time.

For many years I have used non-anodised spi poles and booms and apart from turning a darker variant of gray nothing else happens in the first few years.

In my opinion you can go with it unanodised, although anodising will extent the lifespan from say 10 years to 20 years.

Wouter

We have 7 or 8 Mystere's locally and EVERY one has had a rudder casting crack or break. The boats are all about 10-13 years old and all were anodized. We do sail ALOT here, but i want to do EVERYTHING i can do to extend their corrosion resistance and extend their life span.

I even do a fresh water rinse on my boat every time i sail.

Thanks for everyone's input.

There are plenty of anodizers and platers around you. It will probably cost you less than $20 to get that anodized. Click the link for the list of business around Dunedin that do anodizing and plating. I get stuff anodized all the time.

Google Map Search for Anodizing around Dunedin

Thanks Jake. That price info is good. i was hoping it wouldnt be to expensive (esp since i was told the casting with all parts would cost about $110 each but ended up costing $165.)

I have a friend who is a welder for JSI and i was waitting to hear who they use, but thats great info incase he can't get the data to me.

Are you sure these breakages are the result of oxidising and not of the alu-magnesium alloy age hardening and becoming brittle and then cracking ?

In the end, anodising is nothing more then thorougly oxidising the outer portion of the aluminium component. The desired result is an extra thick and tight layer of alu-oxide on the surface of the alu element. The Alu-oxide then slows down further oxidising to an almost standstill. This is why plain non-anodised alu can be used just as well; only difference is that it will look less cleam (uniform) as natural oxidising looks more greyish then an anodised oxide layer.

But anodising for 20 bucks is something I wouldn't pass over.

Wouter

YES! i am sure, i put the casting under an electron microscope, then sent it off to the CSI crime lab for dusting. I had Smokey the Bear check it for fire damage, and finally McGruff the Crime Dog reasured me it was

not of the alu-magnesium alloy age hardening and becoming brittle.

They all agree that if it could extend its life by 10 years… it was worth the $20 - JUST KIDDING

PS thanks for all the input....

Yikes! I called all 3 local places listed and the costs were $55-$78 (lot charge what ever that means).

I am all in favor of people earning a buck, and making a profit but this turned out to be double the expected costs. I guess that’s to be expected with recreational boating.... grrrrr

Whether they do one, or ten the price will be the same. I'm guess so long as it fits in a certain rack, or tank. Something of that nature anyway.

You mentioned others needing the castings as well. Get a group together, buy as many as you need plus some spares and get them dipped.

I've had aluminum dive tanks (not anodized) for about 15 years (yes, they won't hydro them anymore so I have to ditch them next year).

Used to dive in salt and fresh water (well, they've been sitting in the garage for the past two years) banging around in caverns/caves. Not much paint left on those things....

Thankfully, never had problems with cracking, because 100 Cubic feet of air at 3500 PSI might do more than just

leak

if a crack showed up...

I thought aluminum just oxidized along the surface, and that prevented further oxidation (unless scratched).

Call me old fashioned, but I still think those old US Steel 103 cu.ft. steel tanks were the best ever... didn't float when empty and you could put a lot of bottom mix in 'em. Yes, they do corrode, but I never saw a spot of rust on mine, even where they were banded (doubles). But that's for another thread...

Hmmmm...they're charging you for a whole basket or hanger load...if you tell them you don't care what color they're anodized (or perhaps choose two basic popular colors like clear or black) and that you are flexible on the schedule - see if they can include it with another lot and charge you a fraction of a whole lot...it's a small piece. That, or somehow find some other folks that need things anodized and go in together on a lot.

These companies are used to doing pallet loads of aluminum at a time. We send out two pallets of aluminum parts for anodizing here at Hartness International every day. I bet if you were to go to their office and find someone to speak to face to face, they'll cut you a break.

That's why I suggested a Machine or Sheet Metal shop. They can get you to the right guy to talk to for a small lot, or possibly add your stuff to their load.

Someone suggested this to me: any input?

I’d scuff them down with 400 wet/dry then shoot with any primer and then whatever kind of white lacquer (not enamel) you can find at home depot.

Your other option is to polish them which would actually look pretty cool.

Gotta go with the Wout on this one...systemic rudderhead failures don't sound like a corrosion issue...more like a design issue to me.

Anodizing will not rectify that.

I would agree that the quality is low, and the alum may indeed get brittle and be a part of some of the issues ...
but many of the issues are due to corrosion where the dissimilar metal adjuster screw (and assembly) and the alum casting meet...

I was just looking for a solution to help prevent corrosion and thought that anodizing will help.

I decided to bite the $50 bullet and just get it done. So i drove to the shop and i have now spent $10 in gas driving only to find out i need to remove the rivets and seperate the handle. So if i remove the rivet and return (another $10 in gas) and then go pick them up in 2 days.... It will cost me an additional $30 in gas. Grrrrr

I am now thinking rustolium (or similar) is the answer...

If they are a rough sand casting (like most rudder castings), you're going to be polishing for a LOOOOOOONG time.

Yes... i agree.. that is not an option... esp because i could not get insides very well (atleast not without shredding my hands)... and what would be the point if that didnt protect them throughout...

I don't think anodising solves these issues much either. Alu oxide is conducting and hence galvaic corrosion will progress much like it would with a non-anodised element. This has also been my experience with rivets and eyestraps on alu tubes both anodised and non-anodised. There maybe some measureable difference but not much in a practical sense.

Wouter

Do you think there would be any value (at all) in using a spray can primer and a coat of paint?

Make sure to use a good insulating grease like TefGel or Duralac on contact points between dissimilar metals and leave the castings otherwise naked.

You're Done! Now go sailing and stop driving all over town and wasting your gas 🙂