Friday, July 15, 2005

Brass balls

Link: Liberty Brass

In the field we use brass balls (painted black) to hold our iButton temperature loggers. It's meant to be a modular solution for instances where you already have lots of 1/2" PVC couplers mounted on the shore from other projects. The round brass ball provides a constant projected surface area facing the sun for almost any direction, which means you can rely on having consistent, standardized exposure as the sun moves through the sky. We ordered our balls from the Liberty Brass site linked above. They are willing to drill and put threads in the balls (if you order enough to make it worth their while) so that you can easily mount the balls on 1/2" PVC fittings.

The appropriate size to order is the 1.25" ball, but with a special order 1/2" NPT Pipe thread tapped into it. This allows room for the iButton to fit inside the ball, and allows you to screw in standard PVCfittings. They don't seal completely watertight, but (old-school) iButtons tend to hold up fairly well even when submerged in salt water for a month or two.