Pressure testing

[teckhead]

H i guys, wondering if any diver has made their own pressure tester for there camera (nikonos camera), or do you just send the camera away for this?
here in OZ it,s very expensive to have it service , any where between $250.00 to $340.00 ,AUS dollars, what do you pay over there ?

 

[herman]

Just for a pressure test??? My LSD does that for free. Having the housing rebuilt (oring replaced )is a different matter.

 

[fdog]

The shop I use charges about US$100 to replace all the fixed orings and pressure test. Pressure test alone depends on attitude and how busy they are, maybe $10 and some beers.

Nikonos specifically... I seem to remember a system that involved a hose fitting into a Nikonos case; the camera had a vacuum pulled before you entered the water. Any "leak down" and you'd fix the orings before entering the water. Popular with commercial diving ops, I believe.

For a housing, I'd just throw a lead weight onto the housing (no camera), and dangle it overboard on a line to about 80'. Same thing, and way cheaper.

For a Nikonos, I'm not sure. I'd want to pressure test it someplace where they could fix it if it failed.

All the best, James

 

[daveg1]

Don't know if any of my local shops do that kind of testing, so no idea on cost. I found it easer to just make my own presure pot and do it myself. Made mine to test my can light. Its made from an old steel 72 with the top cut off, and the best part is it works great.

 

[teckhead]

Don't know if any of my local shops do that kind of testing, so no idea on cost. I found it easer to just make my own presure pot and do it myself. Made mine to test my can light. Its made from an old steel 72 with the top cut off, and the best part is it works great.

do you have any photos or spec, like to know if i can make one!

 

[jetski781]

I made a pressure test setup for my Nikonos-V. It is a large water filter housing rated for 100psi and you only need 75psi to test to 50m. Most pressure vessels are tested to 1.5 times their rating so it should easily do 125psi which is my shop air max. I have tested it to 120psi for a couple of hours with no problems. Also the pot is clear so you can see what is going on. Attach a high quality guage on it and you can check the accuracy of your depth guages. I paid $50.00 at Lowes and about $10.00 more in fittings. works great. It also fits the SB105 strobe. It is a Whirlpool WHCF-DWHBB.
1 atmosphere=14.696psi=10m=32.8ft.

 

[MarkH]

I made a pressure test setup for my Nikonos-V. It is a large water filter housing rated for 100psi and you only need 75psi to test to 50m. Most pressure vessels are tested to 1.5 times their rating so it should easily do 125psi which is my shop air max. I have tested it to 120psi for a couple of hours with no problems. Also the pot is clear so you can see what is going on. Attach a high quality guage on it and you can check the accuracy of your depth guages. I paid $50.00 at Lowes and about $10.00 more in fittings. works great. It also fits the SB105 strobe. It is a Whirlpool WHCF-DWHBB.
1 atmosphere=14.696psi=10m=32.8ft.

I don't really understand the concept of pressure testing a Nikonos in air. It's obviously not going to catastrophically collapse on a dive. What you're worried about is the o-rings leaking by. I don't know if you can pressurise a Nikonos in air and be able to tell if there is a small leak or not. It would have to be a big, fast leak to notice a drop on the gauge. Or maybe this is how it is done and I am just confused. If you pressure test it in water and it leaks, you just wrecked your electronics.

 

[jetski781]

Actually you fill the pot with water and submerse the camera in it and then pressurize it. Use distilled water and if the camera leaks you dont have to worry about corrosion like you would if it leaked on a dive. You pressure test it without the batteries in it so no problem with the electronics. Salt water cunducts electricity very well and can ruin electronics and corrode the metal parts in a very short time. Take a nice clean piece of shiny steel dunk it in salt water pull it out and it will start to rust almost immediately. You dont pressure test the camera every time you use it, just before the next big trip. If it floods with distilled water dry it out and send it in for service. If it floods with salt water wash it out and send it in for a very costly repair and you ruined your dive trip. I change my own internal seals and test it after I change them out to make sure everything is seated properly.

 

[firemedic296]

I made a pressure test setup for my Nikonos-V. It is a large water filter housing rated for 100psi and you only need 75psi to test to 50m. Most pressure vessels are tested to 1.5 times their rating so it should easily do 125psi which is my shop air max. I have tested it to 120psi for a couple of hours with no problems. Also the pot is clear so you can see what is going on. Attach a high quality guage on it and you can check the accuracy of your depth guages. I paid $50.00 at Lowes and about $10.00 more in fittings. works great. It also fits the SB105 strobe. It is a Whirlpool WHCF-DWHBB.
1 atmosphere=14.696psi=10m=32.8ft.

correct me if i am wrong. You are right 1ata is approx. 14.7psi
but isin't 1ata=0ft or sea level and 2ata approx 33ft. so wouldn't you need 66 psi to simulate a test to 150 ft. like i said correct me if i am wrong.

 

[jetski781]

technically yes, but No.. The camera when closed is equalized at sea level (1ata). at 10m below the surface the camera is "technically" at 2ata but only has 14.7psi pressure on it. So.. to test the camera to 50m or 5ata below the surface you have to multiply the number of atmospheres below the surface times 14.7. Technically you would be at 6ata but since the camera is equalized to 1ata at the surface it is basically zero.