Entomology - A bee!

All last summer there were no bees, and I had to polinate everything by hand.

The closest thing to a bee in the last year I've seen, was a dead one at my mum's house 10 minutes drive away from my house.

No bees.

They are all dying out everywhere on the planet.

Colony collapse disorder I think it's called.

But I saw one, alive and kicking in my backyard today.

After chasing it around for half an hour as it frantically tried to escape my shade cloth I finally got a pic of it.

Thanks rapid fire camera maker.

Tis a poor pic, but it does prove a bee still lives.

120 Things in 20 years - Entomology - Yay BEE!

Stirling engines - Adjustable Stirling engine crankshaft

I've been busy making the tips of my fingers raw.

Wire seems to enjoy hurting people.

But I love the stuff.

My time learning how to make screw in eyelets for my hand made fishing lures was well spent. Every new skill I pick up seems to inform my next project. Working with wire is a really worthwhile thing to learn.

  • This post appears to be in bullet point style.

One thing I don't really understand is the relationship between the size of the cams on the crankshaft and the performance of my little tin can Stirling engines. With this lack in mind, I thought I'd build a completely adjustable crank shaft.

It looks like this.

With it, it should be easy to try a stack of different configurations to see what they do.

The cams (bits that are offset from the main shaft) should offer different combinations of engine torque, and speed when they are adjusted to different heights.

I think.

Ideally I need an adjustable chamber for the displacer as well. I'll have to feed that idea through the invention engine at some stage because I have no idea on that one.

All the brass fittings come from the brass bits in strip electrical connectors.

Once the screws are undone as far as they can go, all the brass bits fall out with tap and a jiggle.

Lots of taps and jiggles actually, but they all come out in the end.

In my adjustable cam, the brass tubes that accommodate the cams have had an extra hole drilled through. Brass is very easy to drill, and a pleasure to work with. I don't think I've ever done anything with brass before.

I officially like brass.

  • Bullet points

Also, many other people have used these as the adjustable bits on Stirling engines, and my only contribution to the science is to take their use to absurd levels.

120 Things in 20 years - No time to post because I'm too busy learning stuff about Stirling engines.

All the brass bits are taken from a strip of electrical connectors.

Stirling engine ver 2

I made a few changes to My little home made Stirling Engine.

Change is always required when your engine seizes after only 55 seconds.

This one ran until the plastic bits caught fire.

Much better...

The original displacer popped itself to bits when it got hot enough, so this new version has a different design that's open to air travelling through it.

The autopsy also shows why my little engine stopped so suddenly. There is only around a quarter of an inch of air above and below the displacer when it's at it's extremities, and the bottom popping off made the displacer touch the bottom of the can it was in.

I replaced the can surrounding the displacer because I had to use a can opener to get the displacer out, and reattached the power piston balloon.

In the process of building the new displacer can, I discovered a new way to drill a hole that suits my personality perfectly.

You punch a hole with a nail, then rip a circular hole with pointy nose pliers in much the same way as opening an old style tin can of fish that the eater would open with a key.

If you aren't old enough to know what I'm talking about it, count yourself lucky and get on with it. You haven't missed a thing.

I drilled a few large holes in the top and bottom of the displacer, and packed it full of stainless steel, kitchen scrubber pad.

Apparently this works, and acts as a thing called a regenerator.

A regenerator can often be found on a Stirling engine and acts to store heat between the hot and cold sections as the air moves between the two.

The regenerator material collects heat from the freshly heated air inside the can the displacer is in. As the heat is displaced from the hot section to the cold section, some heat is removed and stored in the material. This is a good thing, because we want the cold side of the equation to be as cooled as possible. When the cooled air returns to the hot end, it picks up the heat it dropped into the regenerator on the way through, making it heat up more rapidly.

It's not by magic that the heat knows when to sit and when to be picked up, just that the air is hotter on the way up from the heated section, and has cooled a bit at the top before coming back through the regenerator.

I put the new displacer in it's tin can, and threaded it's wire through the bottom of the top can that holds the crank shaft.

In the process of de-constructing the first version, I bent the shaft a little, and it never ran quite as smoothly again. The little Stirling engine took a lot more heat to get it going this time, but I'm not sure if it was due to the new design of the displacer, or just due to the fact that every thing was a bit warped.

Friction really kills these things, so making sure the shaft is straight is a must.

It does run, and it's going a lot faster than the first version, but I suspect that has to do with all the extra heat from using a gas burner rather than a candle, and not some gain in efficiency.

I think I now know a little more about these interesting engines, and a little more about the universe in general, and I think I'll have another go at building a better one. I'd really like to make one efficient enough to run on the waste heat from my wireless router so it could just jig around all day for free.

120 Things in 20 years is finding the universe yet more interesting as a result of building this version 2 of my first, working, home made Stirling engine.

Stirling Engines - My first Stirling engine build

In spite of my video camera running out of battery during filming, I managed to get the first (and only) moments of my first Stirling engine running.

Tis a funny kind of beast running so slowly and deliberately.

I officially like Stirling engines. Mine looked like this...

It ran for a total of about a minute before the displacer fell to bits. It was sealed airtight, and as it got hot it just popped. It turns out there isn't really any need to make it air tight.

I think.

My displacer started life as a soft drink can.

I marked out a straight line to cut it down to size.

I took a guess as to what size it should be.

I scratched a series of arcs with a bent piece of sharp wire, each at different points, to find the centre, then punctured it with a drawing pin. 

I marked out another can, but this time much shorter.

Then squashed the big one over the little one after turning the little one upside down.
This gave me a sealed can again.

I glued it with super glue.

The gluing was what killed my brand new Stirling  engine after only 60 seconds. As the heat increased, so did the pressure inside the sealed displacer, and eventually it popped open.

I poked a straight length of fencing wire through both holes, then bent and super glued one end to stop it slipping through.

My wire originally had a slight loop at the other end, but I had to cut it off to remake the thing after I glued myself to it.

Don't do that.

And if you want to be really scared, use super glue, then adjust the dials and buttons on your new camera with the same fingers.

Anyway, the main thing is stick some wire through the displacer.

Next I took a tin can and smacked a hole in it with my family's trusty meat mallet.

This meat mallet used to be my mother's (it probably still is), and was used as the household hammer for as long as I can remember.

Here we see the entire family history of hammering.

Actually that's half the family history of hammering. The other half is of course, on the other side.

So then, I took the length of wire sticking out of the displacer (soft drink can thing), and threaded it through the bottom of the tin can.

Like this.

It's a bit difficult to see, but that's the soft drink can displacer thinggy under the tin can.

Next, I took another tin can and drilled a big hole in the side.

And sanded down a small plastic bottle so that it's contour matched the tin can's.

Then cut a really big hole in the side of the small plastic bottle.

Something like a pill bottle would work.
All this, so I could glue the small plastic bottle on the side of the tin can with a big hole in the side. 

Next, I stretched a balloon over the entire little plastic bottle, and pulled the slack so that it was tight everywhere but the top.

I also glued a length of wire to the centre of the slack bit.

This, believe it or not, is something called a "power piston".

I'll explain what all this stuff does later.

Next I bent a crank shaft, and some mounting points for the wires coming from the displacer (through the bottom of the tin can), and the wire glued to the balloon (power piston)

The crankshaft has one offset bit (offset by around 8mm) to attach the displacer's wire, and another to attach the power piston wire to.

The two offset, (bent out) bits, are at 90 degrees to each other.

So from the left...

straight, then down, then straight, then back up to the original.

That makes the first cranky bit.

Then continuing straight, then back, then straight, then forward back to the original plane.

That makes the next cranky bit.

If you look at the crankshaft end on, if one crank was at 12 o'clock, the other would be at 3 o'clock (or 9)

I found this almost impossible to get on camera (or to explain), but it looks like this.

It's probably best seen on the video.

The crankshaft is lightly held in place with two inverted U shaped bits of wire taped to the sides. (just visible near the top, left rim of the device)

I stuck a cardboard disk about the size of a CD onto the end of the shaft to act as a flywheel, and then added nuts and bolts with blu-tac until the thing was balanced.

To get them in the right spot, I put the disk in a random place, and if it rolled back to a different position, I'd stick on a weight so it wouldn't.

I should have been able to do this with just one weight of the correct size, but for some reason it was beyond me.


  • The displacer is the soft drink can thing inside the bottom can. 
  • The bottom can is sealed ([buy - EDIT  - note from the future-  Who makes errors like this?] by the top tin can) except for the small hole in it's top that has the displacers wire poking through.
  • The displacer travels up and down inside the bottom tin can with a total travel of around 1cm.
  • The displacer gets very close to the top and bottom of it's tin can container, but never actually touches.
  • The displacers wire is connected to the crankshaft (between pink beads)
  • The power piston (pink balloon) is floopy, and connects to the crankshaft 90 degrees offset from the displacer's crank.
  • The top tin can is there to hold up all the other kit, and as the top seal for the chamber holding the displacer (soft drink can thing)
  • When the air inside the bottom tin can heats up it expands, forcing the power piston up. This turns the crank and gives the device its power.
  • As the device rotates, and the displacer moves down, forcing the air up and away from the heat, so it cools and contracts. 
  • When it contracts, the power piston is sucked down.
That's pretty much it. Repeat as desired, or until something breaks. 

Some light oil can be added to any surfaces that have friction. (where the displacer wire moves up and down into the bottom tin is a high friction area)

==============>>> IMPORTANT!!! Note from the future - It turns out you probably shouldn't add oil to the point where the wire slides through the can. There's a chance of explosion as the oil is heated to a gas. <<<================

120 things in 20 years - I made a Stirling engine!

Stirling engine - Success!

I just made an engine!

I even think I got it on video.

It ran for about a minute at around 78 rpm before making a popping sound and seizing up.

Which would have been perfect if it was connected to an old record player...

playing a very short song...

that I only wanted to hear once.

The camera battery went flat during filming, but but the video should be on there. I'll find out tomorrow. If not, I'll just fix it.

Yay me!

More later...

120 Things in 20 years is very pleased with itself       :{)

Stirling Engines - My second attempt

I think I may have actually built something.

Or nearly built something.

It looks like this and almost works.

Most of that junk in the picture isn't part of it. The bits that are part of it are the bits that look like a Stirling engine.

Sometimes Stirling engines look like tin cans, and wire, and pink balloons. They also look like cardboard disks with blu-tac stuck weights all over the place to act as a flywheel.

I planned on posting a video of it working today, but it doesn't.

What it does do is spin around freely for a few seconds when you spin the flywheel. It also has a displacer and power piston that are configured in such a way as to do what they are meant to.

I think.

When I put it on the stove top, it nearly feels a bit like it's trying to work, then smoke starts pouring out of the seals, so I take it off the heat before it catches fire.

Who knew tape might burn.

Yes. That's right. I thought I'd make my engine using gaffer tape for the seals.

It doesn't work so well.

Tomorrow, I'll buy some glue. I seem to remember hearing of someone who used two part epoxy on a real engine crankcase, so it should cope with the heat.


My next choice will be solder. Solder melts when you get it hot, so I'm guessing that wont work so well either.

But the glue might.

If it works, I'll put up a big build post. If it doesn't I'll try something different.

120 Things in 20 years - Using a random evolutionary approach to building a Stirling engine. Chuck some bits in a bag, shake, then cull anything that doesn't work like a Stirling engine. I'll get there eventually.

[edit from the future - For anyone concerned that time may not be linear any more, this post was actually written two days ago, but for some reason didn't get posted. As a result the post after this one was actually two days after this one.]

Thinking - Paradise

Paradise is usually documented by pristine beaches that have an opalescent, turquoise quality.

It's just polarised light.

Buy some polarised sunglasses and look at your local beach.

Wear them all the time, and there's no need to fly anywhere!

This tip brought to you in the interest of staying at home. It's got everything you need!

Except broad horizons.

No matter where you are, the horizons are not broad enough.

Travel if you can.

Photography - New (to me) Canon EOS 20D camera

My new camera is a lot like my old camera in so far as they both take pictures, and they are both 8 megapixel cameras.

But after that they diverge a bit.

The Sanyo Xacti that I've been using for the last 1300 photos I've taken was gifted at me by someone (Thanks anonymous company) when I really needed a replacement because all the point and shoot digital cameras I've bought to make this blog (I think it's 3 now) fall over just after 5000 happy snaps.

5000 seems like a lot when I put it in print, but in terms of time, that equates to less than a year per camera.  Sure they cost less than AU$100, but I still want more than a year out of anything I buy.

This one that I've been using is still going strong, and does a pretty good job of it I suppose, but I found the interface very heavy going.

It has quite a few options and features, but all of them have to be accessed via a clunky multi-level menu system. That means that every time you want to do anything other than what it's set to do now, you have to explore a stack of menus to finally find what you need, and by the time you've found it, the ladybird has finished eating it's aphid, and flown away.

My new camera on the other hand is a zillion times better to work with. I've only had it for around 10 hours, but it already feels comfortable.

It's taken around 1200 pictures so far in it's life.

I have very greasy fingers.

I'm eating zucchini and haloumi fritters.


The new camera is a Canon 20D. It was originally sold for around AU$1500 (Australian dollar) in 2004, and was described as a "semi-professional" or "prosumer" camera at the time, which of course means substantially more than other imaginary words and their associated imaginary metrics.

But on the whole, the camera rocks.

That's my official rating out of 5.

It has a 4 GB CF memory card, which is the size of a bulky circa 2012 64GB mp3 player, and that cost around the same as a bulky circa 2012 64GB mp3 player. It takes a while to transfer photos, but it has very nice functionality, and best of all has an interface that works.

It also comes with some nice lumps of glass in the lens. It seems to be the lens that lets down lots of little point and shoot cameras. The quality of the photo's taken by my new 8 megapixel camera is a lot better than those I've taken with an 8 megapixel point and shoot style camera.

The second lens feels a bit like it might blow away, but at $10 it's a very nice thing to have around.

The camera came with a Canon 18-55mm f3.5 image lens, with image stabalizer. I've just discovered I love image stabalizing. Image stabalizing allows you to be a bit shakey, and have the lens do some stuff to fix it.

As I understand it, there are exactly two ways to do image stabilizing.

  • 1. Project an image onto the censor, so that the image is a little larger than the censor, and the image has some extra image in the margins. Then have the camera track your shakey projection, and then use magic or software or something to knit together a nice crisp image.
  • 2. Track some points on the image, and move the lens around a bit so that any given point on the censor always sees the same bit of the image, or move the censor to achieve the same thing.
  • 3. Use gyroscopes mounted on at least two axes to resist the movement of the entire camera. Things spinning around like to keep doing it. If you take the tire off your bike (stop first) and hold the axle while someone else spins it as fast as they can, it becomes difficult to change the angle it's on. This is why a spinning top (do they still have those?) stays upright, and is simply due to the universe being an amazing place.

The camera shows its age through it's 8 megapixelness, as at the time of writing, that's about 16 megapixels short of where it should be.

I bought it from a second hand camera store in Japan for $150 with the Canon 18-55mm zoom, and I got the second lens, a Tamron 100-300 zoom, for $10 from the bargain bin.

Thanks Tom.

Tom's a friend of mine.

He's really good at buying way too much camera gear from junk bins. His hobby includes buying those instamatic film cameras that were big in the 70s. He likes to buy them when they have rolls of film still in them so he can process the film. In some subtle way, that's slightly different from buying some old photos.

Which is nice.

For him.

He's kind of a time traveller, but he only gets to look, and doesn't get to choose what he looks at.

Mostly he gets to look at darkness.

Sometimes darkness, but with slightly mouldy edges.

Luckily, I don't suffer from collecting things other than my collection of odd people I know.

Tom's one of my favourites.

Thanks Tom.

120 Things in 20 years - One of the best parts about getting my new, second hand Canon 20D camera, was getting to look at the Japanese supermarket junkmail it was packed in. It's been 20 years since I was in Japan, and the junkmail paper is now of even better quality.

Stirling engines - My first Stirling engine

Sometimes I struggle a bit with certain aspects of construction, but in this case I wasn't even certain of what I was attempting to construct.

Most of the problems trend around a certain frantic waste of pace and failure to pay attention to detail.

This time was no different.

A Stirling engines basic list of components include a cylinder, a displacer, and a crankshaft.

They also include a hot bit, and a cold bit.

It's the difference between the hot bit and the cold bit that makes a Stirling engine an engine.

There's also another really important bit, called the power piston. The power piston is connected to the same crank shaft, but on another crank. This crank is offset from the displacer's crank by 90 degrees.

I'm not really sure how it does what it does, but this is my first attempt at making a Stirling engine.

The power piston is the bit that's missing, because I didn't get that far.

Some of the other missing bits include the rest of the components that make up a Stirling engine.

120 Things in 20 years - On a scale of one to ten, where one is a total fail, and ten is a total success, I wouldn't bother rating my first attempt at making a Stirling engine.

Stirling engines - A complete history of Engines

Some time ago, somebody invented the steam engine. The steam engine works by heating water in an airtight container to make steam. The steam is massively expanded water, and the result is lots of pressure.  Once you have lots of pressure you bleed a bit of that pressure intermittently into a piston, and the piston gets pushed. Connect that to a crank, and you have rotational motion, and an industrial revolution. You also have lots of factory workers being blown up in hideous, explosive  accidents, with all the screaming, and loss of productivity that goes with being killed.

Later someone invented the internal combustion engine, and the turbine engine. These run on fossil fuel. They had a pretty good run until somebody discovered it was making us sick and killing everyone.

The turbine engine is a big thing you tend to stick to the ground in a power plant and make electricity. That way the factories could all have much safer working conditions where hardly anyone ever got blown up, but it also kills the earth a bit. Just a little every day. And sometimes some of them explode anyway. That's not so good, because some use uranium to make the heat, and that never ends well.


The internal combustion engine tends to be used in portable things like cars, because they pack such a lot of punch for such a small weight in fuel. They also kill the world, just a little bit each day, and sometimes explode, and sometimes just mash into each other, and mash into other things that tend to be near roads. They do a lot of mashing.

The main advantage with the turbine, and internal combustion engines, is that they spread out the damage. Just one or two people from any given factory at any given time get killed by them rather than taking out half the factory's workforce all in one go like a steam engine disaster might. The mayhem and disaster is spread out so that each factory takes just a small share of the disruption to productivity. Except perhaps with the uranium stuff. I think that's why Australia is shipping all our uranium to distant countries. To move it as far away as possible.


A Stirling engine on the other hand is a slightly more peaceful beast that doesn't really do a lot, but what it does, it does pretty thoughtfully. Historically it fits between the steam engine and the stuff we use today (2013, just in case someone reads this in 40 years). The Stirling engine is an engine that uses the difference in heat between two of it's bits of kit, to make stuff spin around without all the explosions.


That's the design description out of the way.

It's very safe, because it doesn't have a pressurised container. It needs a source of heat, but that can be solar, or waste heat from something else. Rotting compost, your wireless router, whatever. They are not a very powerful engine, which is why the internal combustion engine took over, and they are not very responsive to sudden changes in desired power output. That's also why the internal combustion engine took over. And they are not very powerful... Internal combustion engine blah blah blah.


The most beneficial thing as far as I'm concerned is that they wont blow up and kill me.

They're not very useful. But that's not going to stop me making one.

The kind of thing that will stop me making one, is more likely to be that I have no idea how.

I've never made an engine before, and have also never met anyone who has, but it turns out they are a pretty simple kind of beast, and with a bit of luck, wire, string, and the total combined wealth of human knowledge stored on the Internet, I might be able to make one.

People are very clever, and there are some really helpful ones out there that are willing to help me.

I'll be trying to make a very small Stirling engine that runs on the power of a small candle, that will do no work, but will hopefully work.

120 Things in 20 years - Stirling engine - It might go round and round.

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