How to protect a metal housing from flooding and corrosion

[tamas970]

I am a happy owner of a new 10bar Aluminium 6061 housing for my Olympus E-PL5, which I would like to give the best care - I can't afford buying a new set

Question #1: AFAIK, there is no Zinc anode on the housing. Where should I connect one(or more)? Would any normal marine sacrificial anode do the job?

Q#2: Which grease is the best to take care of buttons, screws, o-rings?

Q#3: The screws seem to be stainless steel, which can cause additional corrosion issues. How should I take care of them? Marine grease?

Q#4: Is there a powerful water absorber out there, that gives better survival chanches to the camera in case of a mild leakage?

Q#5: Is there anything I missed? (e.g. removal of anything, that may cause leakage or corrosion - a little fool-proofing)

 

[Hetland]

Different manufacturers recommend different greases for their components. I use one grease for my strobe o-rings, and a different with my camera housing. Check with the manufacturer, or an authorized dealer to see what grease they recommend for their products.

I've been diving with a camera for six years, and I've never greased a bolt, screw, or fitting. After each dive day, and before opening the case, I fill a bucket with fresh water and soak my system for an hour or more. I then remove the system, and wipe it down with a fresh towel in order to mechanically remove any stuck on salt or crud. If it's going to be a while before my next dive, I break down the components, remove the main housing and strobe o-rings, and store in a cool, dry place out of any direct light.

 

[Akimbo]

The best way to protect any housing from leaks is a “smart” vacuum check system:

http://www.scubaboard.com/forums/cl.../449949-want-buy-gates-seal-check-system.html

 

[tamas970]

Thanks for the tips. I was thinking I'll bring a bottle of de-ionized water on the boat and rinse the housing right after the dive.

Unfortunately my housing doesn't have a bulkhead, where I could attach a vacuum-checker. I have to check if the focus/zoom button can be replaced with a vacuum port.
BTW, Overpressure would be a better idea for deep divers (e.g filling the housing with 2-3bar Argon)


Any ideas on DIY Zinc anodes (where to connect them)? would it help, if I screw it in the bottom thread? (If I was a housing manufacturer - especially Aluminimum housing - I'd electrically insulate that...)

 

[Interceptor121]

I think you are getting a bit too worried.
I have had housings without any anode and there is no sign of any problems after years.
Just ring thoroughly at the end of your diving day and press all the buttons. Leave the screws alone
At the end of the trip soak in deionised water and then use a tootbrush to go over all areas where some grit may be stuck
Store in a dry place and that is pretty much it

In some places fresh water is not that fresh so leaving the housing assembled with arms and trays that may have steel parts can cause problems. If your tray is aluminum there is not much of an issue unless you leave it for very long in salt water

 

[Hetland]

If your tray is aluminum there is not much of an issue unless you leave it for very long in salt water

+1

Think of all the metal on your dive gear: steel or aluminum tank, steel tank buckle, steel d-rings, chrome-plated brass regulator, aluminum lights attached to steel bolt snaps. Just thoroughly rinse your gear after each use, and I'm sure you will be fine.

 

[Akimbo]

My Nauticam housing has two tiny bits of metal that I assume are anodes. Several conversations with corrosion engineers leads me to believe that they have very limited value on aluminum that is not continuously grounded and/or exposed to errant electrical currents.

It is not a huge deal to drill a hole for a vacuum system “if” you can find a flat spot large enough for the O-ring… but your warranty will be toast. Personally, I would trade the peace of mind and reliability that a vacuum system provides for a warranty any day… especially since the camera inside isn’t covered anyway.

I would have no hesitation to have Pacific Housing Repair install it if you don’t have a mill or good drill press.

 

[tamas970]

Those pieces won't be in metal-metal contact with the housing - this slows don the process considerably. Anyway, I'll check what can be done. From the equipment side I'll opt for plastic D-rings and snap clips wherever possible. Steel tanks are usually covered with Zinc - at least no problem from this side.

In case I decide for drilling a vacuum port, it is simple to combine the zinc with the valve.

Think of all the metal on your dive gear: steel or aluminum tank, steel tank buckle, steel d-rings, chrome-plated brass regulator, aluminum lights attached to steel bolt snaps. Just thoroughly rinse your gear after each use, and I'm sure you will be fine.

 

[Hetland]

Those pieces won't be in metal-metal contact with the housing - this slows don the process considerably. Anyway, I'll check what can be done. From the equipment side I'll opt for plastic D-rings and snap clips wherever possible. Steel tanks are usually covered with Zinc - at least no problem from this side.

In case I decide for drilling a vacuum port, it is simple to combine the zinc with the valve.

My point is that these other items aren't rusting away. You'll have your camera submerged for how many hours in a year? Probably not enough to justify drilling a hole in order to add a sacrificial anode.

I have an aluminum ULCS tray that's attached to an aluminum handle by a stainless bolt. My housing is attached to the tray with a stainless screw that mates to a stainless fitting. After some 300+ dives, mostly in salt water, it still remains corrosion free.

 

[KeithG]

The best advice to foolproof your setup is to stop fooling around with it. It has been professionally engineered to operate in the environment in which you will use it.

The aluminum housing already has a protective coating on it so the bare aluminum is not exposed to salt water. For the amount of exposure it will get, no additional protection is needed other than proper rinse and cleaning.

I also caution the amount of "o ring care" you give it. In my experience, the people that get floods are the ones that constantly fiddle with their housing. I was once on a live aboard where one chap greased every o ring every dive. He had 2 leaks that week. When questioned, he always had leaks every trip. He thought it was normal.