DIY Compression tester?

[Divemaster-K]

Anyone ever built a small compression test tank for computers and camera housings?

 

[superstar]

I fabricated a small compression chamber on my lunch breaks at work. I use a bicycle pump to pressurise it. It works quite well. I will post some pictures this weekend for you.

 

[Divemaster-K]

That would truly make you a superstar. Also, material specs would be awesome.

Thanks.

 

[daveg1]

Yep built one a few years ago. Used an old steel 72, cut the top off and welded on some blocks to bolt a flat top on. Used a piece of think rubber under the plate to seal the whole thing. Add a couple of holes through the top to add and remove the air and your done.

Now just add water, what you want to test, close it up and add some air on top. 14.7 psi per 33' you want to test to. I have tested my stuff to 150 psi or about 335'.

 

[Charlie99]

Add a couple of holes through the top to add and remove the air and your done.

Now just add water, what you want to test, close it up and add some air on top. 14.7 psi per 33' you want to test to. I have tested my stuff to 150 psi or about 335'.

One of those things that is obvious, once it has been pointed out, is that you should minimize the amount of air in the system. Water is nearly incompressible and so water under pressure stores very little energy. Compressed air stores energy and will release it all if the pressure pot fails.

Kind of like the difference between an air filled scuba tank failing explosively vs. a water filled scuba tank splitting open during a hydrostatic test with very little energy release.

 

[marchand]

Have you thought about using a pressure cooker? I have a rather large one that would work nicely for pressure testing computers and camera housings.

 

[mattjm]

I hear corny kegs (5 gallon soda/beer kegs) work well, if you have any friends that brew they could hook you up. Sometimes good deals can be found on used ones, too.

Kind of a small opening on the top so might not work for a lot of cameras...

corny kegs are rated up to 130psi.

 

[oxyhacker]

There's one in our divelight book which is made from a (failed) aluminum 80 with a clear acrylic plastic top which works nice because you can see though the top, something that is hard to do with corny kegs and garden sprayers and makes the pot very useful for checking gauges and computers. The aluminum tank is much easier to saw than a steel one, and the sidewalls thick enough to accomodate both the studs to hold the top down, and a gasket, so no welding is necessary.

There's a picture on the Airspeed Press website, in the GALLERY section.

 

[PhaedrusDive]

Have a look at he link below. As much as I love DIY, for $40 I could direct my energy to building actual dive gear instead of test equipment. Granted this'll only let you test to 4ATA (130'), but is a great start!

Harbor Freight Tools - Quality Tools at the Lowest Prices

 

[james croft]

I was thinking about 99 FSW at 4ATM.