Wall mounted aquarium PC

So here is the culmination of four months hard work and tinkering.

Why?

There were several reasons for me choosing to make an aquarium PC. Firstly, as an experiment into long term heating effects on hardware. I have had several "always on" and gaming PCs in the past, and they only seem last a year or two before malfunctioning; whether it be the graphics card, memory or HDD at fault (despite having lots of cooling fans). I am hoping that the higher specific heat capacity of oil will facilitate a more consistent temperature throughout the PC, with the internal fans and air bubbler providing a "stirring" effect. If it turns out to be reliable and stable then I will look into building a gaming version!

Finished aquarium

Secondly, as a piece of art. My man-cave is a constantly evolving beast in need of the latest gadgetry and focal points of interest to stimulate conversation.

And lastly, as a way for me to test out the difficulty in working with new materials and tools (specifically thick acrylic) so I can apply these to other projects in the future.

There are lots of other examples on YouTube that I encourage you to take a look at. There is also a commercial desktop aquarium PC that you can buy from Puget Systems that is designed for mineral oil.

9L Aquarium

The Aquarium
The main 9 litre wall mounted aquarium was purchased from a website within the UK for £100. The tank is made from glass which has been stuck together in places using what appears to be a silicone based glue. The tank is encased in an MDF frame with a gloss finish to the forward facing areas. There are two supportive glass struts at the top of the tank, on to which a glass lid is normally placed. These struts now form the main supports to the custom acrylic motherboard mounts as described below.




Inside the Aquarium
I constructed the motherboard and accessory plates from 10mm thick acrylic. This thickness is extremely rigid and will not bend when loaded with hardware. I found it very difficult to work with; a jigsaw blade generates so much heat that the acrylic reseals itself. I had to use a milling machine to cut the two rectangles in the pictures below. Drilling and tapping holes is also "interesting"; I found using rubbing alcohol whilst drilling cooled down the drill bit enough as to not melt the acrylic.

Motherboard and accessory panels

Completed motherboard panel (with some test memory)

Panel supporting USB Relay, Thermometer, TTL LED trigger and SSDs

Assembled panels ready to put inside aquarium

The Oil

5L Silicone Oil

There are hundreds of types of oil that I could have used in this project, ranging from Johnson's Baby and pure mineral oils, to transformer and immersive surgical oils. I ended up opting for Silicone-350 oil since its auto-ignition point is 400 degrees C (well above the 125 degrees C maximum CPU temperature), its viscosity remains almost constant with varying temperatures and it is relatively cheap at £39 per 5 litres from Mistral Lab Supplies.

PC Specifications

This PC has to be energy efficient since it is always left on. I also wanted to avoid having to use an external radiator and so needed to opt for a processor with low heat output; I therefore settled on an Intel Atom based motherboard.

All of the components ready for assembly

I also wanted to have everything submerged, including hard drives, and so bought two SSDs. This also serves as a redundancy if/when one decides to fail.

The specifications are as follows:

• ASRock AD525PV3 Motherboard with built-in Intel Atom D525 processor
• 4GB 1333MHz Ballistix Tracer Memory
• 2x 64GB Samsung Solid State Drives
• 205W Power Supply

Cost

Here is a breakdown of the costs (including postage). Most items are from eBay and some items are second hand.

Wall mounted aquarium: £100
ASRock AD525PV3 Motherboard: £60
4GB Ballistix Tracer Memory: £30
Acrylic for motherboard base plate and I/O panel: £11.20
Shuttle Power Supply Unit: £22.81
USB Wifi Dongle: £3.78
SATA power splitter: £1.55
NM2 nylon standoff spacers: £1.67
MicroSATA to SATA adapters (x2) £1.67 x 2: £3.34
64GB solid state drives (x2) = £55.32 + £45.00: £100.32
RGB LED Tape: £10.79
80mm blue LED fan: £1.57
40mm blue LED fan: £4.95
Power switch: £2.16
10L Silicone-350 Oil: £78
Bio-orb aquarium pump: £8.49
Bio-orb extension cables: £11.98
Silicone hose: £2.34
Bubble bar: £3.19
Glass suckers: £1.98
4-channel usb relay: £22

Total Cost: £482.12

Performance

Please check back to get updates on performance metrics and reliability as I measure them in due course.

Changing the front shock absorber on a 1998 VW Golf Cabrio

Introduction

I recently replaced the front suspension on my 1998 VW Golf Cabrio and thought I'd share a few photos of the process.

Disclaimer: This article is intended for supplementary reference only. This process is dangerous and could result in damage to you and/or your car and void its warranty. Always consult a certified mechanic if you are not confident in carrying out the work yourself, and make sure you read the service manual specific to your car before commencing.

Tools required

- Trolley jack

- Axle stand

- Spanner set

- Socket set

- Spring compressors

- Breaker bar or impact wrench

- Car service manual
- VW suspension nut tool

- 2 hours of time (if all goes well!)

Optional tools
- Blow torch
- Grinder

Difficulty

I found changing the front suspension a real PAIN IN THE ASS. The coil retaining nut was completely rusted solid on the driver's side and they are not accessible without destroying the existing mounting. After cutting off the spring retaining assembly with a grinder, I realised that there wasn't one with the new suspension kit and so had to source one separately. All of the other nuts were very challenging too, requiring 'persuasion' with a blow torch. Only attempt this if you are good at removing rusted nuts!

Method

1. Jack up the car securely and remove the wheel. I recommend using an axle stand as well as the jack, and also placing the wheel underneath in case it collapses whilst you're working on it.

2. Remove the two nuts as shown in figure 1. I needed to use some heat at this stage!
3. Remove the brake line bracket as shown in figure 2.
4. Remove the ABS sensor cable as shown in figure 3.
5. You need to use a special VW suspension nut tool on the top retaining nut. I did not have one of these and couldn't source one in time, so I had to fabricate my own from a 22mm deep socket, using a Dremel (figure 5).
6. Insert an Allen key into the top of the strut and hold it firmly still. Now use a spanner to rotate the removal tool counter-clockwise. Mine was rusted solid and so the blow lamp had to come out again (figure 6).
7. The top retaining plate should now come off, freeing the strut (figure 7). This can then be removed from underneath the car.
8. I then needed to replace the strut. THIS STEP IS DANGEROUS! The coil is compressed with spring compressors. At this stage the spring is storing a huge amount of energy and if suddenly released could cause you or others around you serious injury (see pictures in my other post: http://benjiosaur.blogspot.co.uk/2012/12/changing-rear-shock-absorber-on-1998-vw.html).
9. With the spring compressed, it's now time to start the real fun! Getting the spring retaining nut off. You may be lucky enough for it to not be rusted, if so then great! Otherwise you'll need to find a way of removing the hard-to-get-to nut. There will be entire forums on this :-) As mentioned above, I had to resort to cutting the mounting off and replacing it.

10. I then swapped out the old strut with the new one, and reversed the whole process. I used new mounting components as they came as part of the strut kit, the only original part that I reused was the coil. Please refer to your workshop manual for the correct torque specifications for each nut replaced.
11. Now it is advisable to have your wheels professionally laser aligned. It might sound extravagant but your tracking will most likely be misaligned, causing uneven tyre wear and unstable steering.

Photos

Figure 1. Remove this nut and the one below

Figure 2. Remove the brake line bracket

Figure 3. Remove the ABS sensor cable

Figure 4. Allen key in top of suspension strut

Figure 5. Fabricated suspension removal tool on top mounting nut

Figure 6. Turn suspension tool counter clockwise whilst holding Allen key still

Figure 7. Top retaining plate removed

 Goodluck!

Please leave comments and suggestions below.

Changing the rear shock absorber on a 1998 VW Golf Cabrio

Introduction

I recently replaced the rear suspension on my 1998 VW Golf Cabrio and thought I'd share a few photos of the process.

Disclaimer: This article is intended for supplementary reference only. This process is dangerous and could result in damage to you and/or your car and void its warranty. Always consult a certified mechanic if you are not confident in carrying out the work yourself, and make sure you read the service manual specific to your car before commencing.

Tools required

- Trolley jack

- Axle stand

- Spanner set

- Socket set

- Spring compressors

- Breaker bar or impact wrench

- Car service manual

- 2 hours of time

Difficulty

I found changing the rear suspension much easier than the front. The nuts hadn't rusted tight and unscrewed with ease using a breaker bar. I would recommend this for an intermediate level home mechanic. The most difficult part was prying the hub down and pulling out the existing strut. It should be achievable in under 2 hours.

Method

1. Jack up the car securely and remove the wheel. I recommend using an axle stand as well as the jack, and also placing the wheel underneath in case it collapses whilst you're working on it.

2. Remove the nut as pictured in figure 1. The rear hub should now slowly drop away from the end of the strut. (You may have to push it slightly further).

3. Now go inside the car, and behind the back seat you will find the top suspension mounting. Remove the assembly as per figure 2, making note of the order of the components.

4. The suspension should now be free to remove from the car by pulling it out from underneath (figure 3).

5. I then needed to replace the strut. THIS STEP IS DANGEROUS! The coil is compressed with spring compressors as per figure 4. At this stage the spring is storing a huge amount of energy and if suddenly released could cause you or others around you serious injury.

6. The top nut on the strut can now be removed using a socket and the assembly falls apart as per figure 5.

7. I then swapped out the old strut with the new one, and reversed the whole process. I used new mounting components as they came as part of the strut kit, the only original part that I reused was the coil. Please refer to your workshop manual for the correct torque specifications for each nut replaced.
8. Now it is advisable to have your wheels professionally laser aligned. It might sound extravagant but your tracking will most likely be misaligned, causing uneven tyre wear.

Photos

Figure 1. Remove the nut shown.

Figure 2. Top suspension assembly

Figure 4. Compressed coil. Careful!

Figure 3. New vs. Old suspension strut

Figure 5. Top mounting components

Goodluck!

Please leave any comments or suggestions below.

Do you want to save money this winter? Geo-fence your boiler using your iPhone!

Introduction

With the advent of Apple's iOS 6 comes the ability to use geo-fencing, a way of sending notifications based on your location.

I have often thought about how much money I could save by switching my heating off when no-one is at home, but constantly adjusting the boiler control is impractical given life's changing schedule. However, I set myself the challenge of automating the process as soon as iOS 6 was released.

Warning: This project involves wiring mains voltage and altering your boiler controls. This is hazardous to health and may also break your boiler and void its warranty. Please do not attempt anything I describe below unless you understand these risks.

Required ingredients

• Single channel USB relay (plenty are available on eBay) 
• A smartphone capable of Geo fencing (in this case an Apple iPhone 4) 
• A server (in this case a Windows 7 PC, but in principle you could use something as basic as a Raspberry Pi) 
• A dedicated email account with POP or IMAP access 
• A script to read emails and control the USB relay (I wrote mine using Python)

Wiring up to the boiler

Here are some wiring pictures for the boiler control and thermostat.

Addition of the black wire (sent to USB relay)

Finished product - no visible changes!

USB relay box. Note the three spare relays, hmm what should I control next...

You will see that I have inserted the relay as a switch between the thermostat and boiler control, so all three devices retain control of the boiler.

Note that I have wired the relay up as normally closed. This makes sure that the boiler reverts back to normal if the PC suddenly dies. 

Setting up the smartphone

Here is how I setup my Apple iPhone. I created two notification conditions within the 'Find Friends' app to send an email to my dedicated address for when I leave and arrive at my home address. Luckily (for Apple), everyone in my house has an iPhone and so this process was repeated on each phone in turn.

Free from the Apple App Store

Notification options within the app

Bespoke email address for the boiler!

Creating a script

Here is the script process:

You will receive emails from Find Friends with the subject field reading "Benjiosaur has arrived/left Home". Therefore you set a list of rules to decide whether anyone is in your house, and if not, switch the heating off. I can send you example code if you wish - just send me a message.

Testing

I have tested this app over the last month and it does work well. Notifications are sent from the iPhones within 2-3 minutes of leaving or arriving home, and so far it hasn't let me down. I have thought about a few modifications which may improve the kit:

• Trigger the boiler to also switch on once you leave a destination (e.g. work) so your house is pre-heated upon arrival.
• Replace the boiler controller and thermostat with custom software using temperature probes in and outside the house for optimum efficiency.

I have yet to calculate actual savings for this winter - I will clearly save money if I arrive home late, but I am not so sure if I were to leave for just half an hour or so. When I get some spare time I'll see if I can run a few calculations.

Overall cost

Since I already have an always-on server and iPhone, the cost was literally just for the USB relay (~£30) and a few hours for wiring it in and writing the code.

Goodluck!

Comments and suggestions are welcome, thanks for reading!

Welcome!

Welcome to my Blog! This blog will document any tech projects that I am working on in my spare time, and also ideas to save yourself some money along the way. Please feel free to leave comments and suggestions or to send me an email.