these guys did it before
Read up about a similar project here: some quality hobby engineering. And yes, they didn't restrict themselves to paper.
http://www.members.shaw.ca/sonde/index.htm
We're obliged to all of you who offered suggestions yesterday as to how to adequately join the recently-arrived paper straws which will form the structure of the Paper Aircraft Released Into Space (PARIS) Vulture 1 vehicle. We got straight down to testing a few alternatives, including PVA and superglue, but there was one …
I was somewhat bemused to note that in Aircraft Restoration circles when they restore a Mosquito to flying condition they throw all the wood away and only keep the metal parts...
This is because the glues have a limited lifespan - some 30 - 40 years. Not an isue for Paris of course:-)
I don't want to add a tedious or demanding item to your task list, but I would very much like to know at least approximately what percent of total weight of the plane minus payload is actual paper. Coatings on items not constructed entirely by your crew, such as the aforementioned straws, might prove challenging, but is it too much to ask that each component be weighed before being incorporated into the structure?
[black chopper just because it is also a flier]
Stick a sub-assembly in the freezer overnight and see how it holds up.
I was thinking of suggesting silicone "instant gasket" as an alternative with a wide temperature range, some of those products are quite sticky too. Then I remembered what SRB "O" rings are made of and how they held up when it got a bit chilly.........riiiight.
Any idea what they stick tiles onto Space Shuttles with*?
* @ Anyone saying "chewing gum and spit", yes, very funny, but most of them actually *don't* fall off.
"Any idea what they stick tiles onto Space Shuttles with*?"
NASA calls it "Room Temperature vulcanizing" adhesive which AFAIK is the description of the stuff people use to stick wall tiles up for bathrooms and kitchens.
It's high temperature limits is not quite as high as you might imagine. (IIRC it's something like quite low. I'm pretty sure the tiles would fall off before the maximum use temp of the aluminium body is reached, which is 183c). It's big feature is it can handle the on orbit soak temperature while remaining flexible, which is *very* low, something like -150c to -200c (in theory it could be down to the universal background of 3k but a fair bit of heat leaks out of the orbiter)
The temperature gradient from front face to back face of tile is high.
Your choices for glue are basically A) Cyanoacrylate (Super Glue) or B) Some sort of epoxy.
A) will get you quick dry time, high strength (much higher than the paper it's binding together, anyway,) good low temp performance, and light weight. CA will also work nicely to attach paper to your tube trusses, which will make them quite a bit stronger.
B) will have to be carefully selected from the large array of epoxies out there, will take a while to try, and may require curing at an elevated temperature. The upshot is that there is such a selection out there that you can get basically any performance characteristics you want - high temp, low temp, perfect shear modulus, etc.
The key is to keep the glue as thin as possible, and don't fool yourself about how long that inner piece of the butt joint needs to be - at some point (rule of thumb is about 2x tube radius, one radius inserted into either side) the straws will fail before the joint does, so making that inner piece longer is just going to get you more weight. If 2x radius isn't long enough, put one segment inside the tubes and another outside, that'll balance in-plane torques due to tension and prevent delamination.
Tip: For construction, get yourself a nice ceiling tile and a bunch of large T-pins, print your layout at 100%, put that, covered with plastic wrap on the tile, then use the T-pins to hold pieces in place on top of your print out. That lets you make sure everything fits before gluing, and that it stays put during gluing.
Suggestion: I believe your joint will be stronger if you are able to tease apart the helical joint of one of the two straws to be joined end-to-end. Make a shorter slit in the still intact straw, apply glue, and quickly wrap the helical strip around it. You will end up with a structure that will combine your original method of reducing the diameter of the end of one straw, increasing the diameter of the other straw, and distributing the operational torsion dynamic forces radially and symmetrically.
Side note: Do not be tempted to drink your beer through the straw to test the seal. Drinking beer through a straw make the beer very fizzy and will make you burp uncontrollably. Drinking whiskey (or for that matter whisky) through a straw is OK, though.
...since a man already jumped off a weather balloon 30km up. Too bad the man would dive faster after a few seconds...
What would be the terminal speed of PARIS, assuming the man got faster than Mach 1 (without a plane, that´s commendable) at a given altitude?
Can the terminal speed be guessed, since it is way lighter, but it offers also way less resistance?
Should it survive, won´t it break the world record of 'longest flight of an unpowered paper plane"?
Have you guys looked up Rogallo's experiments? His design amounts to a sail which looks very similar to a paper plane, and it forms the basis for hang-glider and modern stunt kite designs. It also assumes the load (an Apollo capsule for Rogallo; the GPS and camera for PARIS) is slung underneath it for balance, which is kind of sensible.
Are you sure you're not actually thinking of Gemini -- and not Apollo -- as the manned spacecraft originally proposed for the use of the Rogallo gliding 'chute for CM recovery?
Mark Wade writes at:
http://www.astronautix.com/craft/gemlider.htm :
"'Gemini Paraglider'
Manufacturer's Designation: McDonnell-Douglas. Class: Manned. Type: Spacecraft. Destination: Maximum Payload Orbit. Nation: USA. Agency: NASA. Manufacturer: McDonnell.
The paraglider was supposed to be used in the original Gemini program but delays in getting the wing to deploy reliably resulted in it not being flown. McDonnell proposed that additional Gemini missions be flown to fully test the paraglider, which was planned for the follow-on Big Gemini."
Illustrations at:
http://www.astronautix.com/graphics/g/gemparag.jpg
http://www.astronautix.com/graphics/g/gemvar1.jpg
I've always wanted to build an engine out of lignum vitae, just to see of it's possible.
the wood is tougher than most metals and self oiling. (It's so tough, you don't cut it like wood, you machine it like metal!)
But... at the prices it's going for, that'll remain a pipe dream.
( http://www.lignum-vitae.com/ , and there's more on wikipedia, if you're interested)