If we want to use "normal sized" party balloons, which we'll say are less than 1 foot wide, how many would it take to lift a camera? Of course, there are different balloon types (mylar, rubber) and different camera types (gopro, #pi-camera, and bigger). But what are some combinations people have tried that work? I heard from someone that:
Well we put 35 balloons -- 35!!! -- and they would not lift the little camera! At least the first 30 were from the Dollar Store, so $30... but the last five were from the grocery store at $3.99 each, so we spent almost $50 on party balloons and it still wouldn't work.
What are some numbers to help here?
My first thought on this is that the volume of a sphere grows much faster (it's 3 dimensions, so cubed!) than just adding more balloons (which is just linear growth) so, more intuitively (to me), you can look at this diagram from https://science.howstuffworks.com/helium2.htm (fair use low res image):
Is this a question? Click here to post it to the Questions page.
Reply to this comment...
Log in to comment
My other thought is to look at what @oscar-brett has done to design a communal activity around using lots of party balloons:
https://publiclab.org/notes/oscar-brett/5-22-2012/may-day-community-aerial
Also covered in an article in the Community Science Forum in Winter 2012/2013:
https://publiclab.org/wiki/protest-mapping-by-oscar-brett
https://store.publiclab.org/products/grassroots-mapping-forum-issue-3
Also see:
by @Nubu and @stevie!
Reply to this comment...
Log in to comment
I look at this webpage ALL THE TIME:
https://www.balloons.com/HeliumWeightChart.pdf
According to this chart, a regular 11" balloon will lift about .35 ounces (compare it to the 5.5' balloon we use in the kits, which lifts about 5lb).
At .35 ounces per balloon, that works out to roughly 46 balloons per pound of lift . So if you had, say, a three pound camera, you'd want about 138 balloon (a three pound camera would be pretty extreme!)
That said, if you were lifting something like a GoPro (in the neighborhood of 4 ounces) , you could get away with about a dozen balloons. Something like a cheap point and shoot or old cellphone would probably be under 7 ounces (give or take)?
Is this a question? Click here to post it to the Questions page.
Hi, Bronwen -- Thanks for your post. I was doing similar math, but somehow it still didn't work! We were trying to lift a camera of only about 70 grams and we couldn't get it airborne with 35 standard party balloons.
We are at higher altitude (4500 feet) -- does that make a difference? Or, we wondered, any chance the helium is "watered down" since it's expensive now? (We bought all the balloons at our local Dollar Store).
Also, we went with mylar balloons, which @Warren rightfully pointed out are heavier than standard. BUT -- they hold their helium longer.
Long story short, we were trying to find a solution for rural communities that may not have access to helium and hoping they could fill the car with party balloons while in a larger town, then take them to the launch site.
Thanks for the insights, everyone!
Is this a question? Click here to post it to the Questions page.
Reply to this comment...
Log in to comment