Make shift Vac-Bed experimental results

Postby PolygonCactus » Fri Nov 20, 2015 10:56 pm

Hey,

So, I decided to do a little self-bondage, and while I initially thought I'd just do some ropes and stuff, I remembered a far better idea. A while back someone posted a theoretical (I think) idea of using garbage bags and a vacuum to make a vac-bed.

For those of you who don't know, a Vac-Bed is a basically a plastic cocoon, that gets tightened around you by negative air pressure. Basically you suck the air out leaving the person immobilized in the bag.

A garbage bag isn't that big, so I taped 3 of them together to give me a long bag. I cut off the ends of two bags. Then I fed one bad about an inch into the other, pulling it tight around the edges so it was a nice seemless join. Finally it was taped together. I did this again. So you end up with the original, uncut bag at the bottom of the sack, a double ended one in the middle, and finally a double ended one on top for getting in and out of.

Remembering my high school sewing class (how on Earth did they get 30 odd teenagers to sit down and sew, reasonably well in fact, I will never know) I then pulled the sack inside out and did the internal seems as well.

http://imgur.com/4luRbU6 You can see the seam in the middle, and the single layer of transparent tape covering it generously. Pulling the bags tight as you tape gives a clean join with minimal air seepage.

At this point I jumped into the bag (wearing a wetsuit - I didn't want to deal with the sucky end of the hoover and my skin) and stuck the hoover nozzle down. The bag contracted a little, but then the nozzle sucked up the bag blocking itself.

Easy fix! I just need to disperse the suction throughout the bag. I ended up choosing a card-board roll (picture a long toilet roll) used for storing giant posters, it was about as tall as me. I taped off one end and poked holes in it, http://imgur.com/XXxhIym. For extra dispersion, I then wrapped it in a towel http://imgur.com/nfw9JKh. Because the air can go through the towel and any of the holes, it's much harder for the plastic to smother and block the suction.

Now I taped the open end of the tube onto the vacuum head, http://imgur.com/nfw9JKh, and stuck it in a hole at the bottom of the bag. The towel was a pain here, as it all had to slide through the hole (bigger hole = greater risk of tear), but I got it in and taped it up liberally http://imgur.com/Dvv1rlR.

To seal it around my neck I used a rashsuit (swimming top). Basically I pulled my neck through the rashtop's collar, and then stuffed the bag through as well. This provided a decent-enough seal.

Turning on the vacuum was easy enough from inside the bag, I just leaned over and hit the big button (I put the vacuum next to me).

It worked amazingly well! The my lower body was completely inseparable from itself. Obvious this vac-sack had no rigidity like a vac-bed, so I could wiggle around - this allowed me to arc up and hit the button to turn off the vacuum. I wish I'd remembered to take photos at this point, it looks like a real vac-bed with your body tightly encased in the black plastic.

Sadly I couldn't get the neck seal to work when I was lying on my front, which is how I prefer bondage :(. It wasn't too uneffective even then though.

Regardless:

- The tube got kinked badly while I was struggling around (hit the URL cap, it teared), this resulted in loss of pressure near the top of my body (the tube starts at my feet). I think I'll use a PVC pipe in the future, this could even provide rigidity (effectively bonding you to the PVC pole).

- I could use an extension cord to bring the switch into the bag, giving me great control. I'll tape up all the joints so nothing comes apart (and to prevent sweat getting in), and the wetsuit should minimize risk of conductive sweat getting in. I would not attempt this without a modern RCD equipped switchboard.

- This would work great with a timer switch, although I need to find one that runs quickly (normally they're designed for 24-hour use).

- The vacuum is loud as hell, but it could go in a separate room with a bit of piping.

- I could get more interesting with a RPi controlled relay. Although I'm not sure if I trust myself playing with 240v on a circuit board.