They are already waxed ?
So it won't be made entirely from paper then ?
It was with a certain amount of relief that the Paper Aircraft Released Into Space (PARIS) team this morning signed for a cardboard box packed with vital components for the Vulture 1 aircraft. As you know, the principal challenge of our audacious high-altitude vehicle launch project is to construct all the Vulture 1 structure …
So it won't be made entirely from paper then ?
You could so easily have bought artstraws here that are paper... they're not even new-fangled, I remember using them in primary school (which is pushing 3 decades ago) and they're still on sale (random example):
Save you ages on all the butt-jointing and I suggest that a continuous length might be more robust... especially if you were to internally brace the 6mm with 4mm.
This was my first thought too. I wonder why no one at the Reg has used art straws before? they are a universal tool in school, not just for art but, if i remember rightly (and for once i do) building scale model suspention bridges which you then set about placing weights on while the bridge was between two chairs until said bridge snapped, chucking many weights at the floor and making a delightful din. Best week of Design Technology I ever had!
PVA is Poly-vinyl acetate - so your aircraft will be made of paper and plastic. And wax.
Tell you what, you lot source a Vulture 1 miniature camera and APRS/GPS telemetry transmitter made of paper and we'll rethink.
Seriously, though, we can't make a paper plane this size to drop from this altitude without some glueing/treating the structure. We could drop a paper dart folded from an A4 sheet, but that would be the last we'd ever see of it, which would be rather pointless.
However, we do of course always welcome your input. Well, sometimes...
You mean it's *not* going to be a paper dart folded from an A4 sheet?
How disappointing. :(
I think you'll be better off with superglue rather than PVA. PVA is very heavy and rarely used in model building. The Isocyanates are very light once dry and bond paper (or balsa) extremely well. Not sure what effect the wax will have but got to be worth the test.
We have a selection of adhesives here ready for testing. Robin Szemeti's point about waxed paper and PVA is a fair one...
I'd agree that PVA and wax or plastic coated surfaces are a bad combination - PVA won't stick to either. In any case an aliphatic glue is a better choice than PVA though the two are similar. Aliphatics dry hard without the PVA tendency to rubberiness and are more water resistant after they have set.
As a long-time model builder I'm happy to say that aliphatics are still very much in use for balsa and paper or light card structures. and, if used properly, are lighter than cyanoacrylates. The reason is simple: cyanoacrylates polymerise in the presence of water, solidifying the whole glue mass, while PVA/aliphatic sets as the water its dissolved in evaporates, so the set glue weighs less than the glue you squeeze onto the paper. BTW no modeller uses "superglue" - its overpriced and rather weak. The other cyanos you find in model shops (Hot Stuff, ZAP, etc) are far better formulations. They set harder, are less water-soluble and set much more reliably.
BTW, does thin card count as 'paper' for PARIS construction purposes? Seeing that strength and structural stiffness will be much more important than weight for this project, something like a thin card or thick paper (cartridge paper) would be a good starting point, especially as it is easily laminated with PVA type glues. Strong, tapered structures, such as an I-beam for the wing spar are easy to build this way. I think you'll find those straws are too weak unless you use them in fairly large bundles and have a good, light way of holding them together so they can't slide in the bundle.
You need a relatively heavy, fast flying paper aeroplane: even with a glide ratio as low as 1:8 PARIS will cover just over 150 miles from 80,000 feet and, if its sinking speed is as high as 2 m/sec it will still be up there for 3.7 hours and be flying at around 40 mph, so it had better be strong and either set up to fly in circles or to use its GPS to fly into wind or it *will* end up in the North Sea if launched anywhere much east of London - if it had been flown yesterday and set to circle it would have drifted well over 100 miles - the wind at Cambridge was around 25 kts at 2-3000 ft and rising to 40 kts at 28,000 ft. and the longest distance from Cambridge to the North Sea is about 70 miles.
It would be a very good idea to spray or paint PARIS with a non-shrinking, waterproof finish to make sure it doesn't get damp and floppy in flight.
Back in 1992 Michael Johnson wrote "Fantastic Paper Gliders 2", published by Penguin,which features gliders of up to 1 metre span, made from a heavy, glazed paper. The book is 300mm x 380mm with 42 pages including covers and weighs 748 grams, so its material averages 156 grams/sq.metre. The wings are hollow, with a vertical web at the thickest point that forms the main spar. Finding a copy to see the structures would be worthwhile.
Around the same time a set of much smaller Japanese "White Wings" paper models appeared.
These were strong enough to be catapulted 30-40 metres up into the air and flew well. They were made of thin card, laminated with PVA. Bodies were up to 9 laminations and the wing panels were typically three laminations so they would hold a curved wing section. One I still have was made from 0.25mm thin card, wingspan is 200 mm and it weighs 9 grams. By comparison, I recently made a balsa catapult glider of 200 mm span. It has about 30% more wing area, but it weighs only 4 grams and flies at about half the speed. Their glide angles are quite similar.
Finally, someone who knows what he is talking about.
Sounds like a typical IT project to me :
Management : We want a 100% paper plane.
Spods : That's not possible
Management : Just get on with it
Months later :
Spods : We've spent x billion pounds developing paper based computing systems and CCDs. Here it is, 100% paper plane.
Management : Obviously we don't mean 100% paper. We mean you've got to make some ot it out of paper but if there is anything tricky, just buy some cheap off the shelf component instead.
So far, of this 100% paper plane we've got
So, how about defining the project a bit more clearly :
A plane where the airframe and fuselage consists of paper and paper based products, some treated with agents to improve certain characteristics, supporting electronics used to track the [downward plummet | failure to detach].
Might get a bit less flack from those of us who treat phrases like "100% paper" as meaning nothing but paper.
I'm pretty sure you're going to find the wings a bit hard to keep up with paper and you're probably going to want to use some carbon fibre or aluminium strengtheners. It might be worth adding those into the description.
* snigger *
....the water in the butts make the whole contraption far too heavy?
I wouldn't rate your chances of gettign the PVA to stick very well. To work, PVA needs to penetrate the substrate, a waxed straw is designed to keep the moisture (and thus the glue) out. You would have done better with unwaxed ones.
@jasonw these straws go up to 10.5" long and .492" diameter!!
When they make suspension cables for bridges they don't make them out of one big fat wire, they use thousands of tiny ones for a reason... In the same vein four 6mm straws lashed together makes for a stronger member (insert double entendre here) than a single .492" tube (and the art straws are available at least up to 600mm - of if you insist in working in dark age units 23.5" lengths)
Make sure when you 'butt join' that the joint or tube isn't airtight, otherwise all hell will break loose with farting and popping all round.
they could consider leaving an open-ended tailpipe behind the plane- that way the joints can be utterly sealed and as the pressure inside drops it'll naturally equalise.
You'd not want to do it with just bare paper tubes, but these tubes will be waterproof inside and out, so there's no real problem with moisture absorption & freezing / swelling to deal with.
Ditch the PVA go for spray on lacquer or a cellulose dope.
"...otherwise all hell will break loose with farting and popping all round." Just to be clear you are talking about the construction of the plane and not the El Reg team the night after a curry.
*I'm in shorts and a t-shirt why the hell would I need a jacket*
I remember making planes with Balsa, tissue paper and dope. The dope applied to the tissue paper tightened and strengthened the whole plane. I guess balsa is out of the question. A subsitutue might be tightly rolled-up tubes of paper or or triangular folded card board. Experimentation might find the best for strength.
A random search for what "dope" was/is came up with this
I remember the fumes from the dope were quite powerful. Not long after making these I went to Glastonbury and became a keen fan of that special scrumpy they sold there and ...... field of hippies.... wonderful colours.....
Judging by the fact that your "design team" couldn't even find a piece of wood to mount your syringe on at QineteQ I doubt that they will succeed with the straws.
It looked hopelessly amateur.
It might be better if you decide on a design first then mould the lot in PVA soaked newspaper. Something like the Space Shuttle for example.
Mines the one with the sticky pockets
I think you've just realised what gives the project its appeal ;-)
I've heard that somewhere else before now.
But the magistrate was very understanding.
could you not have surreptitiously stolen a bunch of straws from there instead?
Funny but the first thing that came to my mind was polyvinyl alcohol (C2H4O)n not polyvinyl acetate (C4H6O2)n. It did have me wondering for a moment.
That said, I had assumed you would be using corrugated paper for structural support.
Expect a flash of light and a puff of smoke as PARIS succumbs to friction with the atmosphere!
Shirley there's a third-world country that produces aero-space quality paper cylinders. Other than the U.S....
Mines the one with the little umbrellas and straws in the pockets.
"Mines the one with the little umbrellas and straws in the pockets."
I think the PARIS design team will be needing those umbrellas for their deceleration 'chute.
Kick ass and chew bubble gum. (You should maybe forget the gum.)
...you were going to use a single sheet of plain old A4. Well. Well. I won't say cheat but if you are going to use "just paper in any form" perhaps we can incorporate some Paxolin hardening points and movable surfaces and maybe flight control and if it is big enough a real pilot. I mean look what they made the Trabant from. Er... that's probably not a good example.
Right - we had a go putting the straws together with hot glue, which provided an excellent bond. To butt join straws together, we just chopped off a 50mm length of straw, cut a slit in it lengthways (allowing us to "squash it slightly), and glued it into the two ends to be joined. That, ladies and gents, is the how to glue paper straws together problem solved.
Next up, we'll look at how we're going to skin the aircraft, and try some form of waterproof coating (spray lacquer maybe, as some of you have suggested). I post something later today with a couple of pics.
if you look at a modern racing glider (the type you can sit in and fly), they are also built with straws. They are used as spacing material in parts like the nose. PARIS is not so amateur:-)
>And yes, we do have a design, which will slowly be revealed as the plane goes together. Suffice it
>to say, aficionados of vintage gliders will applaud our choice.
The glider from Colditz? or Leonardo DaVincis?
What aboyt epoxy or polyuretane?
Especialy epoxy using the same techniqes as compesite parts (wich it will be anyway) you end up with a (natural) carbon fibre part that might not be as strong as the more commonly used one but still exeeds the requirements for this project.
So what are the rules of what % of the structure is allouwed to be adhesive?