Have a look at this cool High Altitude Balloon Experiment that is unfolding. Bre Pettis (many know him from Make) is one of the people involved with this project. There is lots of construction details and specs. up and tons of construction pictures to look at. The launch date is March 4th so stay tuned…

“This project is launching a (relatively) high altitude balloon carrying a number of digital cameras and some other instrumentation. The project was conceived and is being implemented in a short time with a crowd of eager volunteers and little prior experience and a lot of optimism.
Goal: Get it ready to go this weekend so we can fine tune during the week.

The helium fill system consists of:
* 1 T-bottle of Helium, 2400 psi, 290cf
* A helium regulator with a barb fitting output output epoxyed into constructed PVC pipe adaptor (see below)
* [a fill diffuser?] diffuser determined unnecessary because gas output not strong enough to damage or shred test balloon (condom)
* PVC pipe regular output adaptor: outer diameter of PVC pipe 1.25″, 12″ section joined with right angle elbow to 6″ section to form a L. open end of 12″ section sanded smooth and 6″ end capped—cap drilled to accomodate end of regulator which has been vigorously/permanently epoxyed into endcap. all PVC parts sealed with primer and pipe adhesive.”