ToddK
Contributor
The soda industry abandoned Corney kegs wholesale a few years back, surplusing tens of thousands of them so you can buy new ones for a fraction of their original cost, and used ones for hardly anything. While homebrewing shops have them pretty cheap you can usually find them for even less on ebay, but its worth checking local scrap yards first since they often will turn up in their SS pile where they can be had for a few pennies a lb. I keep thinking I should stock up on them since they have so many uses and one of these days the glut will end and they will shoot up in price.
I got the idea from a book on building your own divelights.
Using a C02 rig to test divelights seems an unecessary complication. I often use just a bicycle pump on mine, when I am testing with it full of water, and a shop compressor or even one of those little 12V tire pumps works fine too. Using leftover scuba air isn't a bad idea but you want to be sure you have some overpressure protection on somewhere between the tank and the keg since 3000 psi could blow it apart (the kegs usually have it already) creating a shrapnel risk in the process. I have an old low pressure two gauge regulator from a shop compressor attached to the LP port of an old scuba 1st stage which I sometimes use to pressurize the test pot, and also to fill tires, clean computers (scuba air is super clean and dry, great for blowing dust out of electronics) and other jobs where I need portable or very clean dry air.
Yeah, I agree. I needed a test vessel quickly, and was unsure of what the connections into and out of the keg were like.