Fanediting a Hoover (DIY Thread)

[WilliamRedRobin]

I'm surprised there's no DIY thread given yet given how long this site's been around, so I thought I'd make one starting with a recent project I've done.

Up until recently, I had been using an old Miele Cat & Dog Turbo 5000 vacuum cleaner that I got from my parents:

This is a top-quality hoover that had faithfully served my family for close to two decades, but unfortunately the lid of the bag chamber stopped sealing properly causing it to pull air in through the lid rather than through the hose.
I took this as a sign that I should probably upgrade to a Dyson like the rest of the developed world, but the thought of such a great machine rotting away in a landfill seemed like a shame to me, and also, I couldn't be bothered to take it to the tip.
So I decided to look for a way to re-use the components.

I've also been setting up a home workshop for electronics work, but the only place I have for it is in a spare room of my house, which raises the issue of solder fumes which at best will make my house stink, and in the case of leaded solder pose a health risk.
The best way to manage solder fumes is to use a portable fume extractor system like this:

Which usually cost a few hundred up to a thousand pounds.
Since I figured that both of these machines are designed to take air from one place and put it in another place, I thought it would be fun to try to turn my hover into a fume extractor.

With that aim, I dismantled the hoover an identified the components that I would need in the new machine.
The circuitry was all very conveniently packaged on a simple PCB fitted to some moulded plastic which could be unplugged from the hoover and lifted straight out.

I assume this design was chosen to make repairs easier and so that Miele could sell replacement circuits, but either way it makes my project a lot easier, since I don't need to rebuild the circuit myself.
The motor was sat underneath the circuit in a housing made of moulded plastic which was made from the two halves of the hoover case.

I wanted to keep this plastic housing to reduce vibration from the motor and provide a good seal between the intake and output of the impeller.

The hoover also had this really cool power cable on a spool which wound up when the button was pressed:

Unfortunately this is way too much for the extractor, but way too cool to throw away, so I'll have to save it for a future project.

I went at the components with a hacksaw to remove anything that wasn't needed and ended up with two neat pieces:

All I had to do from this point was put them in a package that's more suitable for it's new purpose.
I decided that I needed three separate chambers, one for air intake, one for the output, and one for the circuit. Since I wanted these chambers to be reasonably airtight but also be able to take them apart, without any 3D printing or machining I thought the best option would be to use Tupperware-style plastic boxes.

I shopped around to find boxes with the right dimensions and laid them out in a rough plan for the final product.

I also wanted to use one of the old hoover bags to protect the motor from any solids that might get accidentally sucked up.

To connect the intake chamber to the impeller intake while sealing it from the output, I used some pipe fittings that were lying around at work and stuck it to the motor using silicone adhesive.

And I drilled some holes in the side of the boxes to put the pipe through. Sealing them with silicone as well.

For the circuit I used an old laptop power cable and added an overtemperature switch to the live side set at 90° to protect the plastic containers.

Since the neutral line to the control circuit and motor are joined at the plug, I had to splice the new neutral wire into the old one with a small terminal block. Which I did a little sloppily, but when the lid is on the plastic frame keeps it well away from the rest of the circuit, so there's no chance of a short. The plug sticks through the top of the output box so that the motor can plug straight in.

The control dial on the top works by directly turning a potentiometer on the PCB using the white stick you can see in the picture above, so the position of the panel above the circuit had to be precise.

So I cut the bottom off the circuit box and a hole in the lid for the panel. Since I don't have a Dremel, or any other generic-brand rotary tool, and I didn't want to spend days with a Stanley knife and a file to make it just right, I used more of the silicone sealant to stick the panel in, and put the power button in the lid as well.

The original hose connection on the hoover could be detached with some buttons on it, so to keep that functionality, I put that port on the lid of the intake box and used the old hoover hose as the hose for the extractor.

The output blows through a hole in the lid straight out the window.

I gutted one of the hoover heads to use as an intake nozzle, and but It on a microphone stand so that I could move it over my work station and out of the way when I need to.

When I did the first test it didn't pull very well, so I had to take it all apart and re-seal everything, but after I did, it worked great.

On the lowest setting it can pull fumes from about 6 inches an doesn't seem to get too warm from running.

Overall, I spend £20 on boxes, £30 on the mic stand and £3 on the overtemp switch which is a pretty huge saving compared to buying a real fume extractor.
I have a few upgrades planned for the future, like a hose on the output and a second head attached to a chamber, but as it is now, it does everything I need it to.


I hope you enjoyed this weirdly detailed report of my DIY project. If anyone else likes to do stuff like this, I'd love to hear about it.

 

[The Scribbling Man]

Most of photos appear to be broken links, sadly.

 

[WilliamRedRobin]

Sorted, thanks for letting me know!

 

[Jrzag42]

I always love hearing about this kind of stuff, even if I don't understand most of it. I look forward to seeing what else people are making here.

 

[WilliamRedRobin]

I wanted to start another project, so I decided to take apart an old laptop that I got around 2015 and stopped using about two years ago, see what I can figure out about how it works and what I can do to give it new life:

This is what the laptop looked like new:

And this is what it looks like now:

​

The right hinge is broken, the screen's frame is falling apart, the WIFI doesn't work, it can't start up with the battery in, and it's slow as hell.
I don't really need this laptop back in working condition because I already have a suitable replacement, but from this project I hope to salvage as much as I can from it. It has a working screen, camera, microphone, optical drive, speakers and a keyboard. I'm sure I can find a good use for all of these.
Since the laptop started off fast and gradually slowed over time, I think the most likely culprits are the aging hard drive taking longer to read data, or the 6GB of RAM failing to keep up with increasingly demanding Windows updates. I can potentially solve all of these problems with a new hard drive, increased ram and switching to a lighter Linux-based OS. While I don't need another laptop, I could use it for extra storage space for my movies and fanedits. Evan as a dedicated media centre for watching movies. I don't know if there's a hard limit on the bitrate of the video output, but it can at least handle 1080p widescreen, which is the highest resolution I have a display for anyway.
With that in mind I took the laptop apart and tried to identify the components and how they interact

It was a little tricky to begin disassembling it, since it actually comes apart from the top down.
The first component that came out was the keyboard, which is surprisingly thin:

I never realised in the years of using this laptop that the keyboard was a single flat board sat on top of the baseplate. I couldn't see any circuit board in the keyboard, so I think it's just a bunch of buttons and the circuitry is integrated into the laptop's mother board, which the keyboard connects to with a ribbon.
With the last couple of screws hidden beneath the keyboard, the baseplate comes off with a pop and you can see the internals in their full glory:

You can see that the motherboard is only half the size of the actual laptop, and cut into shape to allow room for the cooling fan, hard drive and optical drive.
This board contains the main circuitry of the computer, and all of the periphery components are connected to it in one way or another. You can see the plug for the keyboard on the top left next to the optical drive, for example. The big metal rectangle in the centre is the underside of the bracket around the CPU on which the cooling system is mounted and the square above it is the underside of an unpopulated footprint (more on these later).

On the underside of the baseplate, you can see the circuitry for the power button and the track pad, which are connected to the motherboard in the same way as the keyboard:

In case you've ever wondered how thin inputs and outputs in your laptop work, in this laptop they're soldered directly onto the motherboard:

Individual contacts (pins or strips of metal) in these ports pass current between a track on the motherboard and a wire in the cable connected.

On the right hand side there are two more USBs on their own little board connected to the motherboard by a ribbon hidden under the hard drive.

The hard drive itself is plugged into the motherboard and held in place with two screws.

You might not realise how modular a laptop actually is. There's no reason for manufacturers to invest in proprietary technology, so many components are purchased from third parties, who make their products as universal as possible. And while some manufacturers cough Apple cough go out of their way to make changing components as difficult as possible, most make component replacement simple enough to allow for simple repair and so that they can sell a single model of laptop with a range of specs at a range of prices.
So, if something goes wrong with your laptop, chances are you can repair it yourself if you can identify the faulty component. And if the laptop is shot, there's plenty of very useful spare parts that can be salvaged from it.
I plan on putting this hard drive in my wife's new laptop to test it. If it works well enough, it's a terabyte of storage for my media centre.

Something I definitely didn't expect in this laptop is that the optical drive slides right out!

It's not held in place by anything other than two weak latches and the plug on the motherboard. If you can get a good angle to push it you can remove the drive with very little force.

The optical drive itself is incredibly thin when compared to what you might picture when you think of a CD/DVD drive, it's definitely cool and useful enough for my media player idea, but unfortunately I don't think it has blu-ray capabilities, which would limit me to standard definition when playing from a disc.

In the top-left of the laptop we have the cooling fan, the port for the charger cable, the WIFI card and the main video output to the screen, and in the very top right of this image is the input for the charger cable:

What I found interesting here is that there's no real intake for the fan in the case. There is grate in the bottom below the CPU, but that's quite a distance away. And while the exhaust is on the side of the laptop, it looks to me as if the fan would mostly be blowing up into the baseplate. I'm a layman when it comes to this, but this seems like a very inefficient method of cooling. It would create enough of a pressure difference to pull air in through the bottom grate and across the cooling system, and push it out of the side grate, but it would be moving far less air where it wanted than the fan is capable of, and a lot of the heat transferred into the air would be transferred into the case when the air hits the baseplate. Now that I consider it, I do remember that part of the laptop getting very hot when it was stressed. I can only imagine that these compromises were made to make the laptop as thin as possible, and it would be interesting to know if this is still a common system.

With a couple more screws in the motherboard, and a couple of wires plugged into the bottom that were just a little too small to be convenient, I was able to remove the motherboard entirely and take a look at the underside:

This is where the real meat of the circuit is. Of note here are the plugs for the optical drive and hard drive on the bottom, an SD card type input that I didn't even know the laptop had on the right, and on the left are the connector pins for the battery. The input from the charger cable comes directly into the board through the yellow plug next to it, which means that the laptop can be powered directly by the cable even with no battery installed. At a quick glance the battery plug looks undamaged, so I'll have to inspect the battery itself to see why it wasn't working. Most likely there's some kind of short that draws current away from where it should be going.
The big copper pipe is the colling system. the inside of the pipe has a large surface are like the small intestine, and a small amount of water evaporates in the hottest part of the pipe, absorbing energy from it's surroundings, and condenses in the coolest part of the pipe, dumping the energy. This allows the fan to cool the CPU remotely by blowing air over one end of the pipe to absorb the energy in it and send it outside the machine. Underneath the black square in the middle is the CPU, where the majority of the computer's functions are performed. The constant switching of transistors in this component cause it to have a very high impedance, getting higher the more switching that is done. The higher the impedance, the higher the power consumption, which means that this component gets very hot. And the more the computer does, the hotter it gets. The black square is clamped tightly onto the CPU with an electrically insulating, but thermally conductive paste in between to allow for maximum heat transfer to the cooling system, which should hopefully prevent the CPU from overheating. Traditionally, this cooling is done by a heatsink, a big chunk of thermally conductive metal with a large surface area, that allows it to be quickly cooled by blowing air across it. The copper pipe is called a heat pipe, and is a much lower-profile alternative that allows the cooling system to fit into a laptop, since heatsinks are usually at least a few cm tall.
The two cards next to the CPU are the RAM, which stores temporary data for the CPU to read from and write to so that it doesn't have to hold onto that data itself.
A few other points of interest are the small chip above the RAM which holds the "BIOS", a small set of code that dictates how the components interact with one another when power is provided to the board. This code is what tells the computer what it's doing in the first place allowing it to boot properly. The term "boot" comes from the fact that the computer is "pulling itself up by it's bootstraps" rather than having to be manually programmed every time it's turned on. If I decide to run a new OS on this board, I'll have to change the code that's in the BIOS.
Next to the RAM is a coin battery that provides power to the BIOS to prevent the loss of "volatile data" which is forgotten when power to the BIOS is lost.
The bigger square chip with "ene" written on it is a power management chip. Going by it's location I assume it's there the provide variable power to the optical drive.
The tiny chip above that one is "Flash Memory" a type of memory that is non-volatile and rewritable. This is where the term "flash drive" for a memory stick comes from. I believe this chip is used to store permanent data like system settings, logins, etc. that you wouldn't want to be stored on a removable drive.
Somewhere in there is a clock chip, but I couldn't find it. The clock chip sends very high frequency pulses to the CPU in order to trigger the transistors inside the CPU to switch. The faster the clock pulses, the faster the switching, the higher the power consumption and heat generation. The clock chip pulses at a set frequency, but there are ways to increase that frequency in order to improve processing speeds. That practice is what you might have hear of as "Overclocking", but I don't think I'll be needing to do that for my project.
Finally, There's the empty squares full of dots in the bottom-left. These are locations where components can be installed to the motherboard. The dots are solder that is there to connect those components to the rest of the circuit. It's not uncommon for circuit boards in electronics like this to have unpopulated footprints. Sometimes they're leftover from previous revisions, meant for alternative configurations, or available for debugging purposes. These footprints in particular look like they could be for an optional GPU, a secondary processer that takes over some of the functions from the CPU to allow for greater processing power. Sometimes these components need to be cooled the same as (or even more) than the CPU, but I can't see any sign of a GPU cooling system on this board, so it's likely that the GPUs available for this machine weren't powerful enough to warrant their own cooling.

With the motherboard out I could get the last few components:

Looking closer at the WIFI card, I believe the black wire coming off it is the antenna which went up into the frame of the screen, and it appears to have been snapped.

This would explain why the WIFI stopped working, and should be pretty easy to replace.

And this is what the speakers in a laptop look like:

I think the actual "Speaker" parts are just those small oblong indents on either side. The circuitry for the speakers is probably inside the chunkier side, and the size of the plastic holders is likely just so that they can be securely fixed in place to prevent rattling. It will be interesting to see whether these speakers can take raw audio signals or if some of the processing was done on the motherboard as appears to be the case with the keyboard. But either way, I'm sure I can find an interesting use for these.

That's all for the disassembly of the main laptop.
This was mainly a fun learning exercise for me. I've always sort-of seen laptops as a single block that works as a unit, but obviously there's a lot of individual components that go into it, and finding out how each component works and how they can be utilised elsewhere will be a fun exercise in itself.

There's still the screen disassembly to come, and I'll be thinking about how to approach projects using these components, but for now I'll leave it at this.