[drcrash] sent in this thorough how-to on converting a cheap bike pump to pull a vacuum. Apparently it’s just the thing for small vacuum bagging projects. I’m thinking that this could be combined with a low rpm motor and a pivot. Just picture an old steam locomotive wheel drive, and you should get my idea. (A windshield wiper motor would probably be perfect.)
Sorry guys, I’ve got to comment on this one.
[tylin] sent in this “DIY SCUBA” youtube video. These guys used a home shop air compressor with a particle filter so they could “SCUBA dive”. This kid is lucky he didn’t die.
I guarantee there were impurities in the compressed air. A major concern here is carbon monoxide, among others. That filter they used is designed to reduce particles, not scrub out CO, CO2, etc. Hemoglobin loves CO even more than dear old O2, so he could have asphixiated or suffered from convulsions despite having an air supply.
He’s lucky he didn’t blow his lungs out. The second he took a remotely full breath off that hose, he started to float up. If he happened to hold his breath it would have ruptured his lungs and caused all sorts of nasty problems.
He wasn’t wearing a weight belt – furthering the risk of floating up when he took a breath. (in my experience about 90% of people are positively buoyant)
4)Nobody was in the water watching his back. If he’d suffered any complications, no-one was there to make sure he didn’t drown. (Think convulsions, black out, etc)
Sorry for the rant – but this is just effing stupid. Don’t try this crap, ever. I’m an advanced open water diver myself - get training and real equipment.
Update: The video was removed after reading my response to it. I went ahead and puled the youtube link since it’s useless.