Epic adventurer - DIY paracord bungee that should outlast the polar caps

Making a home made paracord* bungee** to take my new and very small Gerber Dime® multi tool on any epic adventures I may set off on turned out to be pretty worth while. Claiming that it will outlast the polar caps probably isn't saying that much.

Oh well.

I wanted to make it so I could use my new little multi tool while it was still attached to my belt so I couldn't lose it overboard, but didn't want it dangling around my ankles when I let it go without re-clipping it. I figured if I wasn't actively using it, I'd clip it to my belt, but when I was using it, I could just it to still be attached. That would mean there was a loop of rope hanging down a foot or so from my belt, and I thought that might be annoying. I have a bungee cord with a hook at each end thats been sitting in water outside in the sun for 3 years and is still in perfect condition, but I have also bought a few dozen that didn't make it 3 months. I have no idea what brand the good one is, but even if I did, it's too think for my requirements.

The invention engine said I should make my own.

I started with some paracord and removed all the inner strands. If they are tight, just pull one out at a time until they come out with ease.

The mess should look something like this when complete.

The next step was to cut a length of inner tube into a strip thin enough to fit inside the hollowed out para cord.

I cut a length around 30cm long, and around 2mm wide

Try to avoid any nicks and rough edges as this is where it will break if stretched too far.

But we wont be stretching our too far so it wont matter.

I then threaded a thin wire through the hollow  length of paracord, bent a loop, and tied the strip of inner tube to it.

I attached to other end of the wire to my house because it was the only heavy thing I could find.

With the help of some pliers to grip the paracord, it was simple to pull the strip of inner tube back through the empty paracord.

I added a decent quality swivel from my fishing gear as an afterthought, but it would have been a lot neater to incorporate it into the knot so it might lie in a straight line to the DIY paracord bungee.

As it is in this pic, I can stretch it to around twice the relaxed length.

In later experiments, I discovered that if you scrunch the length of paracord bungee into a rough ball, then roll it around between your palms as if you were rolling a ball of dough, it gains extra creases and folds. This allows you to untie it, and shorten the length of inner tube inside, and as a result bunch up the paracord.

So now I can get a stretch of around 3 times the relaxed length.

To get maximum stretch, bunch up the paracord until it's still slack when you stretch it. This means the inner tube is the limiting factor. Then let a little paracord slip through your fingers until the inner tube is still fully stretched, but the paracord is also tight.

Tie it off, and you should be set. As long as you didn't stretch the inner tube too much before tying it off, the paracord should take any extreme force that's applied, and your rubber inner should stay intact for the next 25,000 years or so.

All in all this suggestion from the invention engine turned out well.

The short length of very thin and super strong DIY paracord bungee is ideal to suspend my new favorite tool.



120 Things in 20 years - Oh look, a post!



* strong, thin, light, multi strand rope you use to hang from parachutes
** rubbery rope you use to tie things to your roof rack, or tie your ankle to a bridge with when you are about to fling yourself off.

Aquaponics - Solids removal

I'm actually a firm subscriber to the idea of leaving all solids in your aquaponics system, but I don't really have anything to inform that decision other than my thinking it. 

So we cant have that.

A healthy system can absorb a lot of fish waste and solids break down in no time. There are worms to help with that in the growbeds, but even without worms, friendly bacteria are always there to do their thing.

There's also the point that removing solids is removing hard earned nutrient from your system that the plants need.

There's also the fact that as my system stands now, I have a nice feeling that I'm working comfortably within natures guidelines and margins for error.

But enough of the sensible reasons for not messing about with solids removal. I'm going to have a go at it.

There are a few experiments from my recent past that I can call on. One is the swirl filter and it's followup, the self cleaning swirl filter. The self cleaning swirl filter was designed to separate solids, but keep them in the system, and I encourage you to click on the "self cleaning" link if you feel you might enjoy watching a video of fish poo swirling and settling. The reason I made it was to gain a source of clean water for my NFT (Nutrient film technique) pipes, but it might prove useful in this current endeavour.

I might also need a bit of electronics.

And an invention engine.

And a bit of a mental shift. I think I need to focus on water removal or recovery rather than solids removal. I need to get the water solids mix dryer and dryer.

Currently my plan looks a bit like this...

Step 1. Split the solids from the majority of the water flow using one of my self cleaning swirl filters. I suspect I'll be able to take out 90% of the water at this stage. It look like I might be able to do this stem more than once to get even more water out.

Step 2. Further separate the solids using gentle flow of the remaining water over or through a mechanical filter. Apparently, this will take the form of a conveyor belt sieve that slowly or perhaps intermittently eases solids from a water bath. At least that's what the invention engine seems to think. 

Step 3. Automatically convey the solids to a worm farm so I can add household veggie scraps and create high protein fish food. By returning the fish waste as fish food, I can still keep a natural eco-loop going, and continue to feel good about my system. Also, the fish really like the worms, and in winter when silver perch go off their pellet feed, it might be a good way to keep them growing.

Two things the final design will need to accomplish are that it will need to be very reliable, and that it will need to be very automated. I'll need to be able to go away for a week and ignore the system, and I'll need to create some failsafe system to make sure that I dont end up overloading the growbeds.

There is a great danger of overloading the system, because in order to have enough nutrient for the plants, I'm going to have to overstock my system with fish if I'm going to remove most of the solid waste.




120 Things in 20 years sees me cautiously optimistic about an automatic, aquaponics, solids removing, worm farm addition to my system.

Thinking - The Invention Engine

These last few weeks have found me often running the same question through the invention engine to see if I can contribute in some way to getting the power requirements of an aquaponics system down low enough that it becomes viable to run from a solar panel, or at least to try to make it cost as little atmospheric carbon as possible.

I just keep running the same question through the invention engine with the new parameters. ie "NOT all the stuff that's been thought of before".

I remember reading about some design software that made TV antennae that I think were built into the TVs and were created using a printed circuit board that had a zillion lines that related to harmonics of the frequencies (or something - it may have been a dream - and if so, I just had an idea) But the result was you couldn't patent the design, or rather there was no point, because there were a zillion combinations of lines that would work just as well or better than the first one the design software would spit out.

All the opposition would have to do is run similar software with an additional "NOT that one those other people made" bit of code and they would have a brand new invention that worked just as well but was very different.

The people who made the software would use it to solve problems (like the travelling sales[person] problem for people.

The travelling salesman problem has been around for a long time, and there are a lot of different approaches to solving it. This made me very aware of the "NOT that one approach".

Often I'll come up with a solution, just for a plumbing problem or something, and run the problem again with the "NOT that last solution" added into the thinking process, just in case there is another option.

So far, every single time I've tried it, there has always been more than one solution to even complicated ideas and inventions.

It makes me want to put the invention engine through itself with the "NOT that one clause" added.

That should be it's final test. The downside being that I might have to start testing again from scratch.



120 Things in 20 years is now a place where I'm thinking you may soon see me get stuck in an endless loop of testing the invention engine process by re-inventing the invention engine with the invention engine, then re-inventing that with the new invention engine. Forever.

Aquaponics - The Bullwinkle sequencer Success!

I'll put together a "how to" post describing the build as soon as I can, but I just thought I would share this now.

A flow splitter might be a useful thing to someone with a small fishtank, and a lot of grow beds. It allows you to fill your growbeds in turn from the same water supply without forcing your fish to flap about on fry land as their water is all transferred to the garden.



As far as I know this is an original idea, and as such offer it freely to the world to do as you please with it. You may make it, duplicate it, sell it, profit from it.

I would ask that if you improve on the design that you also give it freely to the world.

I also ask you you let me know if you make one so at least I know my work have been helpful to someone. I enjoy seeing other people make my lure designs, and would love to see a working flow splitter. Personally I have no use for this, so I'll probably never see it in actual use. This idea came about because of a request, and was a test of a problem solving method I'm working on that I call "the invention engine".

Please comment, suggest improvements etc. Feedback would be greatly appreciated.



[edit from the future - There is some additional material on sequencers. Readers might find this newer version in a post titled  The Bullwinkle sequencer build of interest. It's a better design, and only costs around AU$15 to build with off the shelf PVC components]

Aquaponics - Ultra slow flow siphon problem

For some time now I've been working on an approach to invention and problem solving that, in my house, has become dramatically known as "The Invention Engine". It's a formalized structure to problem solving, and so far it's been working very well. It's all in my head at the moment, but at some stage I'll put it out to the world in some form. I'm testing the process again by finding a solution to triggering a siphon with an ultra slow flow.

In some recent trials, it looks like there may be some advantages to a constant flood grow beds, rather than flood and drain. This relies on having highly oxygenated water, but you should have that anyway because that's what your fish like. Some plants prefer flood and drain, but a lot seem to enjoy constant flood.

I can't help but think that one potential downside to constant flood, is that there may be areas that could  become stagnant. Flood and drain, on the other hand, pulls all the water out on each cycle, so there are no areas that miss out on turnover with new water. My fear is that it might be possible that constant flood could leave some areas to could go rotten over time.

I thought I might make a grow bed that was constant flood for most of an hour, drained once quickly, then have it repeat that pattern for ever.

Tricky.

Constant flood works by having a standpipe sticking up through the bottom of your grow bed at the height you desire the water to sit. You pump water in constantly, and it overflows into the fish tank via the standpipe.

So my solution would be to put a bell over the standpipe, but with an oversized standpipe that would be too big for the flow, so that it didn't trigger.

Now all we need to do is introduce a new, quick flow of water once every hour to trigger the siphon.

The Invention Engine first casually mentioned I should just put a second pump on a timer, and have it supply the hourly additional dump of water. I told it that a solution like that was too easy and expensive, and really needed a rethink.

I added the following parameters...

1. that it should require no additional pump
2. that it should require no electronics or timers

The Invention Engine suggested I divert a flow of water to a bucket sitting over the grow bed, put a second bell siphon in it, and have the water dump quickly to trigger the main siphon.

"OK" I  said. But how do you make a siphon that takes an hour to trigger, but still delivers a rush of water to the grow bed. A siphon with a very slow inflow can only trigger if it had a very small standpipe. Any flow that took an hour to fill a bucket, would only trigger a tiny siphon, and only deliver a tiny amount of additional water to the grow bed. A tiny additional flow would mean some very accurate calibrations to make the grow bed's main siphon trigger. In fact it might not be possible, and would definitely not be reliable.

"Make it huge" The Invention Engine replied.

"I want it small" I insisted.

"Oh" said The Invention Engine, "A small bucket that takes an hour to fill, but then dumps quickly?  That's a different question altogether".