Sunday, February 5, 2012

70 km round the bay and back..

Great ride in Melb today with about ten others...


Trialing a friction drive 6354 outrunner with sensorless controller

Sunday, November 27, 2011

It all fits

Trial is successful. Aprilia enjoy battery box will fit three 8s 5.8 amphour packs. Two long format and one in the 4 by 2 format. Can't wait to ride tomorrow...


Monday, October 3, 2011

Now there are two!

Brought another. Cant have done more than 10km.

Aprilia Enjoy Race. Upgraded to 1100watts.

Parts list per requests.

Lbd14 yiyun controller from tncscooters.com (choose this 24volt controller so low voltage cutout isnt a problem. Itll work fine at 33.6 volts). Check ebay for "LBD14"
Generic 3 wire throttle of your choice
30v digital voltmeter from ebay, works ok at 33.6v.
Two Turnigy 5.8amp-hour 8s 25 Lipo batteries from Hobbyking or ebay.
Turnigy 8s balance charger from Hobbyking.
Pack of ten pairs of 5.5mm bullet connectors from ebay.
Duct tape, hookup wire, soldering iron about 25 watts, tools.

Friday, September 9, 2011

Found a tiny 3phase alternator inside this windup torch

I was surprised to find a tiny 3phase alternator inside this wind up torch from the hiking shop. It would make a great experimental platform for wind turbine building.

I will hook it up to a wattmeter soon and see how much it generates back through the gear train at each stage.

Thursday, September 8, 2011

Bafang motor and ebay controller.

My homebrew Nokia ghetto battery is a great source for testing. I didn't know how I would go hooking up a 3 phase brushless controller. It turned out almost as easy as the brushed one on the aprilia. Main difference was only having one key wire. 


Sunday, September 4, 2011

Solar Dryer concept sketch

After seeing Miele's horrifically complex design (link in previous post) I thought I would put a sketch together. Time to build a proof of concept now I have the rough layout in mind.

The heat comes either as waste from our outdoor gas blower (Brivis Buffalo) or the solar reflector underneath the tumbler unit.
Motion comes from a sub-10watt motor mounted on one of the four jockey wheels (shown in yellow). It could be conventionally powered or solar - as it's power is tiny.
Airflow comes from either a solar fan or a solar chimney (cold air is drawn up and heated, so rises and pulls through).

Moisture could be condensed and captured.

I might need a heat exchanger if the waste gas smells of CNG.

I like the idea of a square tumbler to give churning to the clothes, and is removable as a washing basket.
Ergonomics need thinking thru, as do pinch points...

Hope it makes sense.


Wednesday, August 31, 2011

Solar Dryer Ideas

A dryer is just a heater and a motor to tumble the contents.

Looking for alternatives around my home:
Heat Sources:

Motion Sources:
Fridge Waste Heat Too small
Mains Elec Motor Prob ok, low watts
Solar PV Heat Too expensive
Hand Crank Convenience
Solar Radiant Heat Need a site close to house
Solar pump Too complex
Gas Heater Waste Heat Minor Gas smell?


Electric Heat Currently the problem


Thinking about it some more, our gas heater outside discharges a lot of waste heat, so it's the candidate. And it runs on days when you can't use a clothesline.

A small idler motor run from mains power or DC would be ok as it would need only 50 watts or so. Thats not a lot out of the 4000 watts our dryer uses.

I think it would be convenient to make it so the washing basket becomes the tumbler. I hate hanging up washing on lines, which I suspect is why some people use dryers on sunny days. And lots of everyday items come out good enough to not need ironing. The device would need to be ergonomic with no risk of pinch points or combustion if too hot at a point.

You can say 'lazy' - but in the world of management we call this 'efficient'. :P

**Addendum 5/8/11: Looks like Miele has come up with a horribly complex solution - as only the great over-engineers could. Lose further points for integrating it into the building...
http://www.gizmag.com/miele-solar-heated-dryer/19680/



Energy Use - typical values at home

We've been thinking of ways to reduce our dryer usage at home - if you look at the biggest item down the bottom you'll see why:

Item Hourly Watts
6 Cree LED Downlights 18
6 Halogen Downlights 50
Electric Blanket 75
Desktop PC 250
LCD TV 300
PS3 350
Washing Machine 350
Radiant 2 Light Bathroom Heater 500
Fridge 750
Aircon (small) 750
Espresso Machine 750
Kettle 1000
Vacuum 1000
Clothes Iron 1000
Microwave 1000
Oil Filled Radiator 1500
Aircon (big) 1500
Clothes Dryer 4000

The above typical values are per hour. Kettles and microwaves look to be high but they don't get used much.

But when it comes to clothes dryers you don't have many options but to use them for a long time when it is wet outside. Searching online results in lots of suggestions to use your clothes line. Which isn't any help at all if it's raining.

it's impossible to find an 'efficient' clothes dryer as they are really a big electrical resistor to make lots of heat, with a small motor to roll the clothes around.

But I have some ideas for later.


What an interesting device - the self powered (wood stove) ecofan

A thermoelectric generator runs a fan that sheds the heat the unit pulls up from the base, via fins.

http://navitron.org.uk/product_detail.php?proID=265&catID=67


Tuesday, August 30, 2011

Solar concentrator - parabolic trough

I have been thinking about taking a cheap 10 to 20w solar panel and directing a lot more light to it via a parabolic trough. People seem to be doing this using simple convective liquid cooling and upping the amount of light by a factor of 5 to 10. Here is a company doing it commercially link It's an extreme example - there is a smaller domestic application to be had.

Or flipping the original idea around, it could be that the main purpose of the device is to pump heat via a liquid - using a small integrated solar panel. An easy unit to relocate if cooling is built in too.

I like the idea of a trough over a dish, as is it will track the sun fairly well during the day, and just need monthly angular adjustments of inclination.

I don't want a point focus like a normal parabola, so by using chunky segments on the reflector (could be cheaper to make) I can spread the reflected light over the surface of the panel.

I did some experimenting in Google Sketchup with reflective angles versus the width of each segment on the parabola and came up with the following diagram:
It looks like the rule of thumb is to make the higher ribs about half the width of the solar panel, but lower down it becomes less important, so the same width is ok. There is a portion directly below the panel that will be shadowed.

Here's my concept:


Solar concentrator - linear reflector

This would be very easy to do - place a cheap reflective surface below fixed panels.

The incidental sun hitting the cheap reflector would direct extra energy to the panel. Extra light would be gained in the morning/afternoon as well, due to reflection of angular light.
Extra light can cause extra heat/inefficiency, or even damage, so the amount would need to be tested.

Some folks online seem to be directing up to 5 or 10 times the light without damage.
Interesting.

Monday, August 29, 2011

Four Bed Rotation Gardening

I created a new file from all the info I had - I keep losing my references. And when I have space to plant and bags of seeds piled up it gets hard to remember what-to-put-where.

Now I can print a copy and put it up in the greenhouse. You can click for the larger version, right click to download.


Sunday, August 28, 2011

Lithium Batteries for bike lights

samdidgaf - Lithium Batteries for bike lights - A'ME heated bike grips


I still have a lot of these old Nokia batts. I soldered three into series (see my other warnings below!) and hooked it up to my hacked bike light (a 4 watt downlight globe inside the orginal bike light).

I got about 15 minutes use before it cut out - but I don't know how well the frankenbattery was charged. I'll give it a full charge and hook it up to my 30 dollar wattmeter and see.


Just this morning I read about the A'ME heated bike grips and thought it would be easy to make bike handle heaters with a few of these batteries, some resistance wire and a motor speed controller to regulate the current/temp.
Might give it a try.

Saturday, August 27, 2011

The solar powered hothouse

I've now got a 40W solar panel and a charge controller ready to boost the light into the evening, I just need to find a battery and hook it all up. Probably heading into the wrong time of year but why not do it anyway.

But what we have planted so far has been really taking off!


Sunday, August 14, 2011

Mum, I bought a Bafang

Brought my wife a hubmotor so she can come riding with me and the kids. Speed controller is on it's way.

We'd better find a bike for her too I suppose....
And I'll need to learn to lace a hub into a rim. I hope youtube can oblige.


Saturday, August 6, 2011

Soldering mobile phone batteries

There are lots of warnings online about doing this - 99 percent of which come from other warnings about doing this. Viral behaviour.

But they aren't without caution - lithium fires happen.

I had a lot of old mobile phone batteries to waste, a 25 watt soldering iron was perfect for joining them up in parallel. I'm hoping they will make a nice range extender battery for my bike if not discharged too fast....

Keep a big bucket of sand handy - if you do try this  - at your own peril.  No liability accepted.

30 volts, ten ampere hours in theory.






Friday, August 5, 2011

Rebuilding my Aprilia Enjoy - Voltmeter

I found these cheap voltmeters on ebay - about 4 dolalrs delivered.

They make a nice replacement to the Standard Aprilia LED unit. It makes for a good way to ensure I don't discharge my LiPo batteries past 29.6 volts.

Shown below with the old NiMh battery inserted into the bike - hence the low reading.

I removed the bezel from the new ebay unit, dremeled out a new area inside the old aprilia backing, and put the clear cover back on. Magic.I even added a waterproof switch thru one of the Aprilia's standard bolt holes in the plastic cover - shown with the controller still hanging out....




Putting a high powered LED bulb into the Aprilia's stock lamp

I wanted to put a 12V LiPo (made from 3 mobile batteries in series) into the remaing battery case space for auxiliary power and lights.

It got me thinking about the stock light (the generator makes so much noise). So I bought a cheap 4W LED bulb from ebay (the kind that replace your halogen downlights). Then I hacked the back out of the standard aprilia fitting with some sidecutters to make room.

Then I pushed in the globe and soldered on some leads. The globe was held firm by puting some 1 inch lengths of 2mm rubber coated electrical cable around the perimeter of the bulb and pushing/wedging it in with a screwdriver's tip.
A quick test and the unit is good to reassemble. The unit barely gets warm at all - those LED's produce a lot of light and negligible heat.

Now to mount it on the bike. I'll make up a bigger battery pack and put a switch and fuse in line.

Friday, July 29, 2011

Rebuilding my Aprilia Enjoy - battery box

I took the old NiMh batteries out and put in these turnigy units from hobbyking.com

Boy they are fast! The wattmeter can plug in or out. I added a 60amp mini fuse too. Important.

It was an easy job in the end....





Friday, July 15, 2011

Rebuilding my Aprilia Enjoy

I've totally rebuilt myAprilia Enjoy e-bike. Thes e-bikes are gold.

After taking off the pedal assist and replacing it with a normal throttle and speed controller I have lifted the silly 200W power restriction. 1,000 watts is much better (safer) for getting out of the way. And the old 'state of the art' NiMh batteries are now shiny new Lithium Poly batteries at twice the capacity, stashed neatly inside the old battery box.

I can now get to work in a similar time to my car trip, and my knees can have a chance to warm up.
I love it.


Friday, July 1, 2011

A solar powered / wind powered hothouse - one day

I am putting up a hothouse which will run on the four bed rotation system like my other outdoor vegie beds.

But I am hoping to run lights to boost performance over winter - Ballarat gets cold! More planning needed....



Friday, June 3, 2011

Horizontal Axis Wind Turbine (HAWT) bearing from waterpipe

It's easy to make a set of blades, but hard to find a central bearing that is cheap, waterproof and can have an alternator integrated.

So I came up with this unit inside 90mm waterpipe.

The hub and ends are polyethylene cutting boards. Bearings and 25mm neodymium magnets can be pressed into holes cut with spade bits.









I haven't added any internal copper coils yet. Soon.

Wednesday, April 27, 2011

A stepper motor as a wind turbine?

I brought this little stepper motor from Oatley Electronics.

I had hoped that it would generate a decent voltage as it is rated at 24 volts as a motor.
I set about working out which of the six leads formed each of the two coils. Two leads were center tap ones and can be ignored. I found the two pairs in the end by drawing the following diagram and using a multimeter to record the resistance between pairs.
I hooked the inout shaft up to my battery drill and gave it a spin. I could get about 10 volts out, but only a few milliamps. Multiplying the two it didnt really equate to any decent output in watts.

It would be easy to make a little battery charger to charge very small batteries but I am after a lot more to charge my electric bike and such.

A good experiment.