So, you're the kind of person that may let your mobile phone inside your trousers pocket when it goes to the washing machine?

Or are you the kind of person that may accidentally drop the old brick in the water? Sure you are. That is why this Instructable is for you.

I will be presenting you a way of protecting a mobile phone from water damage. Two weeks ago, my mobile went for a bath. I managed to fix it, and I will tell you how to prevent the kind of damage I found inside it.

How water damages circuits:

Water isn't the big threat. Short circuits are. When a circuit gets wet, most likely it will short-out. The second thing that causes damages are oxide bridges. You ask what oxide bridges are: water corrodes the metal in the circuit, causing oxide to build-up. That effect is caused by water and salts dissolved in it. If water can't touch metal, no corrosion can take place.

Step 1: Gather Weapons & Ammo!

What you should need:

- Torx T6 screwdriver
- Acetone if your circuit is greasy
- Paint brush
- Something to contain used solvent
- Electrical tape
- Swabs
- Petroleum jelly
- Guitar pick or something similar
- A piece of string

Of course, you should work with gloves so as not to get varnish or acetone in your hands or unwanted grease in the circuit board.

Step 2: Tearing the Bugger Apart.

Take off the covers, remove battery, SIM card and keypad.

Proceed to remove the 6 T6 screws and put them somewhere safe (not the bank, the government might steal them).

Third photo shows what you get.

From this step on, take precautions against static. Touch the grounding pins on the wall socked. Ups, sorry. You might not reach it somewhere in the world. What can I do? Touch something grounded instead.

Alternatively, you can sledge-hammer it all.

Step 3: LCD Off!

The phone is made out of modules. Just unplug the LCD and take it all apart.

Step 4: Shields

Flipping the board, you will see the metal shields that cover parts of the circuit. These need to come out. Just use your fingers.

Step 5: Degreasing

This might not be essential, but my phone had contact cleaner residues. Wash with solvent and brush and dry. Wear gloves during and after the process and from this step on, work on a very clean surface.

Step 6: Places You Don't Want Coated With Varnish

There are contact patches in the board that connect it to the various modules. These are to be absolutely free of varnish. Get you swabs, some petroleum jelly and coat the contact patches. Also, tape the LCD socket and vibrator unit.

Step 7: Real Business

Tie the string to the circuit, go outside and spray it with an even coat of varnish. Add a second coating if you want, but only after the first one is dry.

This is what it should look like in the end. I know the coating isn't perfect, the spray head was almost broken.

Now everything's ready for the next step. You're almost done.

Step 8: Clean Contact Patches

See what petroleum jelly is good for? It creates a unset surface where varnish can be scraped easily with blunt tools like the guitar pick. After you scrape all of the contacts, you can assemble the phone and test it.

Step 9: Assemble and Test

Now, put it all back together and turn it on. It should be working unless you screwed up!

Step 10: Done

You're done! If you done it right, the next time it gets wet, the water won't corrode any delicate part of the circuit and just drying it well should be the only thing you need.

Have fun doing good stuff.