DIY Solar PV Immersion Water Heater

My Mum and Dad have had a 3KW solar panel system installed over a year ago and my dad has been pleased but wanted to make more of them by heating the hot water as well. He had been looking at options like Immersun that cost anything from £349 upwards. This seemed a bit much and we were sure we could come up with a cheaper and just as effective way of doing the same job.

We found a website called http://www.talkingsolar.co.uk/. A cleaver man on there had come up with a circuit that uses an Arduino Uno. 

This is the circuit I found via a link on www.talkingsolar.co.uk

My job was also made a lot easier as a board design had been made and all I had to do was etch the boards, solder it up and assemble it! All I needed was a shopping list of parts to buy or acquire from work. (With my boss's permission!)

Triac BTA41-600B   Spiratronics (all order inc delivery £11.40)

Opto couple MOC3041-M  Spiratronics

Op amp LM358AN Spiratronics

Diode 1N914 Schottky  Free (Had Already)

8pin ic socket (Had Already)

Arduino UNO  £12.90

CT SCT-013-030  £6.87  eBay

PCB Transformer 3VA 9V+9V Spiratronics

Terminal block 2 way x5  Spiratronics

3.5mm stereo pcb jack  Free (Had Already)

Resistor 180R .25w metal film Free (Had Already)

Resistor 330R .25w metal film Free (Had Already)

Resistor 360R .25w metal film Free (Had Already)

Resistor 12K .25w metal film Free (Had Already)

Resistor 15K .25w metal film  Maplin £1.40

Resistor 150K .25w metal film Maplin £0.96

Fuse holder CPC £0.66

PSU for Arduino 12V .5A Free (Had Already)

Case 194.5x145x78mm  eBay The Allendale stores  £6.90

Heatsink Free (From Scrap Plasma TV)

Cable glands PG11 x 2 CPC £1.10 (only used one in the end)

Ferric chloride EBay £5.19 ( had lots left for future projects)

Total = £47.38

Here is the assembled box just before we installed it.

Here is the finished and installed "Magic Box" (as my dad calls it)

It works much better than I had hoped, my dad has turned off the gas heating for the hot water and so far he reckons that the water is hotter than it was before and they are saving on there gas bill!

Job done! 

Diy 3D Printer Made From Scrap!!!!

This is my blog to attempt a build of a 3D Printer based on the RepRap Prusa Mendel i2.

I have been looking at getting a 3D printer but have been put off by the cost. The cheapest off the self kit I have seen in the UK is the Velleman K8200 at Maplin for £699.99.

I work as an electronics engineer repairing laptops, ink and laser printers and audio equipment. As I work in electronics I am hoping that I can get reclaimed parts from work. (With my bosses permission)

Today I start the long process of hoarding what I can. I have saved an HP printer/scanner from the bin and have reclaimed a smooth rod approximately 400mm long.A piece of glass for the print plate surface? Some springs (might come in) and 2 optical sensors I hope to use end stop stop sensors, instead of mechanical switches.

I still have a long list of parts to get but I have to start somewhere! 

I've bought a Tap and Die set today from a car boot sale cost me a massive £7. Thought it might allow me to have a go at making a hot end for the printer if I'm feeling brave! Bargain, couldn't resist!!!

Just been car booting (yes again!) lol. Got a set of brackets that I may be able to use in the construction of the frame. Cost only £1. Am trying to source either free or cheap aluminum frame material or make from wood? (Not ideal as heavy) we will see

As you might have guessed i have had a bit of a change of mind. I was going for the RepRap Prusa Mendel i2. I have now changed my mind a bit and decided on a 3D Drag or as it is known at Maplin the Velleman K8200 as I mentioned earlier in this blog.

I has found some step by step assembly instructions at http://reprap.org/wiki/3drag#Download and seems more sturdy (we will see). It uses 4 instead of 5 stepper motors that will immediately save on the cost of parts I will have to purchase. 

This is what I am trying to achieve! 

http://www.open-electronics.org/3drag-the-open-electronics-way-to-reprap/

I have managed to get 2 more smooth rods and drive belts from a scrap Dell Printer, at least be able to use the 

Smooth rods not too sure about the drive belts.

Update on this project! (At last)!

Unfortunately I decided to call it a day on building my own 3d printer.

The main reason was that the cost of essential parts like stepper motors and electronics was going to bring it into the £300 ish cost and I didn't want to spend that kind on money on something that might not work or work very well. :( 

I have kept the parts I acquired for any future projects so thay won't go to waste.

I decided to buy a 3d printer instead!!!!!

I was looking for a while and decided to go for a Makerbot clone. It's a Duplicator 4 with Dual extruders. It is basically the same as a Replicator printer, probably with lower quality motors and electronics but the software it runs is the same and seems to produce good prints.

This is the model I got!

The printer had a couple of things I wanted to change. The first was the light in the printer. 

When the printer is on is a bright blue. This looks quite good but isn't very practical as the light doesn't show the item being printed very well for photos or seeing how the print is going.

I bought a 24v led strip from ebay and it was a simple matter of soldering the new one in its place.

You can see for yourself the difference in the photo below but the difference in real life is much more noticeable. 

The next upgrade I wanted to do was to enclose the printer as this would improve the print quality I am getting. This is achieved by preventing drafts and keeping a more even temperature in the printer so the plastic cools at a more even rate.

You can buy a ready made enclosure kit but I wanted to see what I could achieve myself.

As I work in electronic repair I have access to scrap LCD TVs. When they are scrapped we stip them down into parts to recycle. In the back of an LCD or LED tv screen there is usually a piece of Perspex that is clear apart from some small white dots that help in lighting the tv screen uniformly. I've used a couple of these to create my enclosure.

The best way I found was to score and snap the pieces to make the sizes needed. The sides were then drilled and bolted into place. 

The top I stuck with tape to hold it into possition and used clear silicon to joint the parts together.

The door is a temporary solution as I'm not that happy with the look of it and the hinges aren't the best type. I may design some hinges myself and cut another piece of plastic to fit better but it does the job for now.

In all I am quite please with what I have achieved and my prints are improving, probably partly due to the enclosure and me learning as I go. 

Watch this space for my projects I'm working on. The main ones are a Star Trek Phase Rifle and the cassette player from Gardians of the Galaxy! :)

Thanks for reading and hope you will come back to see how my projects are progressing.