When you come to the end of a toilet roll you are left with a stubby section of virtually useless cardboard tubing.

One Tube Deserves Another requires a slightly new manufacturing system, and though it involves the consumption of more cardboard, the result is a tube that has the potential for a useful outcome.

To understand the idea, think of two tubes of the same length, but one fits inside the other. Now imagine the inner tube is pushed out by a half inch and fused into position. This means that the tube now has a "male" end and a "female" end.

This enables the empty cardboard tubes to fit together and be used as a simple construction material.
-- xenzag, Dec 12 2007

Illustration https://sodabred.tu...erves-another-its-a
The start of something big... my first effort with Illustrator CS [xenzag, Dec 17 2007, last modified Apr 14 2018]

Congreve rocket https://en.wikipedi...iki/Congreve_rocket
Most entertaining [8th of 7, Apr 23 2018]

//virtually useless// Now *that's* a challenge! {starts compiling mental list of 101 uses for a dead toilet roll}
-- pertinax, Dec 13 2007


BUN! This would be good for recycling too!
-- Jscotty, Dec 13 2007


Every 5th of these could have flexible pleats (like a flexible drinking straw) so you can build curvy piping. Every 10th of them could have an interior hole so you can make branches.
-- phundug, Dec 13 2007


edit - (I inserted the rest of the second sentence)
[phundu] if all of the toilet rolls were available as either "straights" or "curves", then many forms could be constructed. The degree of cuvature of the rolls could be printed on the outside.
"6 pack of bog roll please" - "Certainly Sir - straights or curves?" - "Eh, 3 shallow arcs, one acute, and two straights"
-- xenzag, Dec 14 2007


Excellent idea. Some tubes should be capped at the end, so you can finish off your constructions neatly.
-- hippo, Dec 14 2007


If this is part of a range of bathroom products, then the lids of, pehaps, bottles of powder, or packaging for toilet cistern blocks could be designed to be neatly fitting "caps" for the tubes.
-- 8th of 7, Dec 14 2007


No T joints, then?
-- RayfordSteele, Dec 14 2007


See re-posted illustration - tumblr
-- xenzag, Apr 14 2018


As far as I can see, this allows you to make various structures including (a) a tube.
-- MaxwellBuchanan, Apr 14 2018


What's needed here is tee and elbow pieces, similar to the ones you can get for plumbing purposes.

I'm not sure how to wind toilet roll onto a T-shaped tube, but that's a minor detail.
-- Wrongfellow, Apr 14 2018


If the tubes were slightly tapered they could join without the extra extra
-- pocmloc, Apr 14 2018


// I'm not sure how to wind toilet roll onto a T-shaped tube, //

We would suggest a "triangular" wrap, successive turns around each arm in sequence.

That's the easy bit; the hard part is designing an inexpensive device from which the paper can unspool smoothly, without snagging.
-- 8th of 7, Apr 14 2018


Actually, you could just make all the tubes with a hole in the side, into which another tube could be inserted, to produce a T.

However, as I have pointed out elsewhere, today's loo rolls are flaccid, insubstantial things compared to the the loo rolls of yesteryear.
-- MaxwellBuchanan, Apr 14 2018


True. They're designed to be a perfect match for the modern bum.
-- xenzag, Apr 14 2018


(+) Missed this when it was posted.

There's a similar thing you can do with the tubes from flooring stores. If you cut them sideways with a hole-saw of the same diameter they stack up like perfect little log cabins.
-- 2 fries shy of a happy meal, Apr 14 2018


[2fries], you really need to get out more and meet people. Even we're starting to think of you as "a bit weird, actually", which is not good ...
-- 8th of 7, Apr 14 2018


//perfect little log cabins//

Beautiful.
-- pertinax, Apr 14 2018


Just make half of the rolls with a smaller diameter so there is a snug fit when the small one is inserted in the large one. This makes them stronger without additional material. Holes for making tees or stacking as log cabins (as suggested by others) should be pre-perforated.
-- scad mientist, Apr 14 2018


// Even we're starting to think of you as "a bit weird, actually", which is not good ...//

Well then I'm sure that will change when tell you all about the awesome cat trees you can make with them!
There's fur trees, catalpas, pussy willows, sugar-meowples, catcuses, junipurrs, mewcaliptus...
-- 2 fries shy of a happy meal, Apr 15 2018


<runs away, waving arms and screaming/>
-- 8th of 7, Apr 15 2018


Leave it to the Borg to find weirdness a bad thing, even around here…

Another benefit of this idea might be increased tube wall thickness, resulting in tubes that are less likely to get squished in the package and then not roll nicely on the holder.
-- notexactly, Apr 19 2018


The tubes in RV toilet paper rolls are so dense you could probably make fireworks from them.
-- 2 fries shy of a happy meal, Apr 21 2018


You mean firework casings (unless you're proposing to nitrate them) .

They're OK, but the cores from fax paper rolls (remember them ?) are better, particularly for making rockets.
-- 8th of 7, Apr 21 2018


Yes that is what I meant.
As for model rocket motors, I haven't seen anything that works better for a home-made rocket shell than an expended CO2 cartridge. They have just the right venturi shape, and those strike-anywhere wooded match heads with their own oxidizer work far better as a propellant than black powder.
-- 2 fries shy of a happy meal, Apr 23 2018


A CO2 fire extinguisher casing made from aluminium can do an impressive impersonation of a JATO bottle if treated kindly. A short length of threaded thick wall steel pipe screwed into the top will provide an acceptable nozzle, although they do erode fairly fast.

Very similar to <link>.
-- 8th of 7, Apr 23 2018


//although they do erode fairly fast. //

ooh... <waggles fingers> stages...
-- 2 fries shy of a happy meal, Apr 24 2018



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