Aquatica A300 Replacing O-Rings

So I finally got my o-ring set for my Aquatica A300 housing. (Thanks Ryan)

It was finally time to change all the o-rings out and give the housing a good scrubbing. I took the entire unit apart. Here's a writeup and updates as I get this housing back in order.

Tools Needed

Screwdrivers, flat and cross

Allen drivers

Long Nose pliers

Dental Pick (Plastic)

Ultrasonic Cleaner

CLR (Calcium, Lime, Rust remover)

Lint-Free wipes

Silicon lub

2 beers

A few plastic bins (to hold parts)

Vacuum pump and/or pressure chamber

Step 1 - Taking things apart

Take the allen keys and take the knobs off the housing. Make sure you don't lose the set screw. Remove the set screw as there is going to be a lot of oxidation underneath. (From mating SS to Al) Make sure you don't lose the plastic washers. In the case of all shafts, just push gently and it will slide out. All the 1/4" shafts have two small o-rings that you need to get off. You can either cut them off or pick them off and safe them. I typically save them for spare parts. Do not scratch the shafts. There most likely will be some calcium/hard water buildup on it. Don't scratch it off. Next, pop out the plastic ports by pressing them out. Take the o-rings off that as well. Set those aside as they won't need to go into the Ultrasonic cleaner. Now for the buttons. Remove the rubber caps on the inside. Then remove the retaining clips on the button shafts. Be careful as they can spring off into the abyss of carpets. Just push the button out. There will be a double seal o-ring, plastic washer, Stainless Steel Spring. Mine was filled with oxidation powder. Repeat until all the parts are out. Make sure you take out the anode underneath the housing. Remove the strobe connectors and shutter switch/cable assy.

Step 2 - Cleaning all the parts

Since I am pretty lazy and not wanting to scrub anything, I popped everything into the ultrasonic cleaner. For those that don't have one, get one. It's a great tool for cleaning almost everything. I made a 10 part solution of CLR and RO/DI water. Filled the unit up and places parts inside. Almost instant, the solution started knocking off all the deposits on the shafts, turning it back into bright and shiny Stainless Steel. (Imagine a housing made all of SS) All the knobs and buttons are all now nice and clean. Springs and all.

I let it sit in the ultrasonic cleaner for 20 minutes. I noticed the solution was starting to turn black. Apperently, the hard coating on the inside of the housing is suppose to be anodized and which it is. There were a few spots where a black marking pen was used to cover up spots that were either scratched or missed.

Take all the parts and rinse with clean water. I used RO/DI water to wash and rinse again.

Place it on towels and wipe dry. Time for beers.

Stay tune as tonight, I will put it back together...

Curtis

Make sure you don't cut the o-rings on the lip of the bore as you try to slide them in. (Speaking from experience). It's a tight fit.

Cheers

James

Thanks. I did that once on a sony plastic housing for the PS-1 3.3mpix camera. Found that the leak was just a few drops, no gushing floods.

How many have really flooded a camera dead?

That was a problem I also had with my A100 housing - certain rods were very difficult to replace without shearing the oring.

Sliding a rod in from back to beginning of the "O" ring gland groove helps guide "O" ring inserted from front into position. Make the rod out of clear acylic with a light bulb at its other end and you have illumination. Then be careful you have not twisted the "O" ring during installation............

What size ultrasonic cleaner do you have that holds the housing? How much should I expect to pay for one? I've seen the little jewelry ones, but I think I'd need something like

http://wttool.com/p/3094-0105

To hold my A20 bits.

How many dives, how long did you wait to do the cleaning?

I got the Crest 1.5 gallon Ultrasonic Cleaner. It's just enough to put half of the housing in. Had to do a few batches.

Step 3 - O-Rings

Pain in the ass to get the o-rings on all the shafts and buttons. As James mention in earlier posts, it's quite easy to slice the o-rings if not carefull. Many holes are quite sharp. I found a trick that works well. Use a blunt dental pick and gently press on the o-ring while twisting the knob. The shaft slides in smoothly.

Putting everything back together is not to hard. The most pain in the ass part was putting the spring loaded release shaft. Had to align it up and adjust the trigger points. Note : Take pictures before you take things apart!

I forgot to mention another thing I did to my housing. Because many of the shaft holes were very sharp, I drilled out all inside holes with a deburring bit. This will make the next rebuild a bit faster.

Step 4 - Water Test

Will this darn thing leak? Well I did a quick dunk test in a 5 gallon bucket. No leaks. Exercised all the buttons a few times. No leaks still. Put 10lbs of soft weights and let it sit for 1 hr. No leaks.

Since I don't have a pressure chamber, I wanted to simulate the housing at various depths. What I did was create a vacuum inside the housing. I milled out a plate that fits the front port. I started slowly pumping out air and started pressing the buttons underwater. No leaks. I varied the vacuum to simulate a very crazy dive profile. If you dove my vacuum pressure simulator, you will most likely need a chamber.

Step 5 - Dive

I'm planning on diving this saturday and hope everything works out well. Will do a first dive without camera inside, just to be certain my mathmatical skills were correct.

Now that you see, it's not too hard to do your own o-rings chang out. Since most of us here dive in remote spots without factory support, it's good to know how to take things apart and slap it back together. I carry a Fluke meter in my bag all the time.

Send me a few lines and let me know if this was helpful.

Curtis

You will only be able to simulate one atm of pressure (ie a 10m dive) by using a complete vacuum inside the housing.

So instead, just lower it overboard on a rope w/ no camera inside...:-)

Cheers

James

True, I just varied the partial vacuum to sorta simulate it. Just dunking it overboard just tests the static pressure, not real world working pressure. I wish i had a pressure pot with acuators to test the buttons.

James, arn't you suppose to be on your honeymoon?