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Slides from my exam…

Final exam from Tom Lynch

Open Source Vacuum Cleaner

The initial reaction from presenting the Open Source Vacuum Cleaner on Adafruit’s Show and Tell has been great, they’re said some wonderful things…

Ask An Engineer

“The Open Source Vacuum Cleaner is now one of my favourite projects, it happened that fast!”

“It’s one of those, why didn’t we think of that, of course!”

“The Open Source Vacuum Cleaner is some thing that would be useful for every hackerspace.”

“This is a really, really good idea.”

Show and Tell

“I want your Open Source Vacuum Cleaner more than the next Dyson that comes out.”

Mark II – Parts

The following is a list of the parts used in the Mark II vacuum cleaner, unfortunately it shows that it was impossible to buy everything from one place in one go because we didn’t have a strong plan, however it almost all was aquired from the Farnborough industrial estate where there is a Maplin, B&Q, Wickes, and ScrewFix. The Travis Perkins we visited was only because we wanted to research alternative bins before spending money on a builders bucket, but they had them at B&Q, Wickes, and Screwfix so we could have choosen one of thier products.

Open Source Vacuum Cleaner #2



The above is the (slightly broken) results of the second prototype. The purpose of this prototype was to build a functional version, and to experiment with having another person build the device to figure out how to enable someone to build there own.

The Vacuum Cleaner was also an experiement in a couple of other different ways…

1. The Vacuum Cleaner was built out of parts predomenantly from B&Q which was a test to see how feasible (and expensive) this might be.

2. The distance to Vacuum Cleaner experiment. The idea here was to test how far I would have to travel to build a vacuum cleaner. Even in the country side, we managed it within 15 miles radius.

3. How long would it take to build an Vacuum Cleaner: 1 week

The entire build of this Vacuum Cleaner from store to end was about cobbling something together with the principals I defined to someone who had not a clue about how a Vacuum Cleaner actually works.

The result as you can see is a quirky and yet fully functional and powerful Vacuum Cleaner. The  hardest parts to obtain are the motor, hose and tools. These problems are easily negated by hacking an older unit, or ordering from a spare parts supplier.

So what’s next?
The working prototype is great, however I would like to produce one more vacuum cleaner that has the nice, aesthetic finish, and if not actually working could theoretically work.

This design needs to have the beauty of a piece of furniture, something like an Eames classic is my current thought, I am looking for help with this as I am not a product designer, if any of you could help me at all it would be appreciated, there are only a couple more weeks left until the project concludes however.


I have decided to maintain a Github repo for all of the final parts for my version 1 release of the documentation, Git Hub supports files, has a pages feature and a Wiki feature so I can produce a page about the project with some marketing about it. A wiki as the documentation on how to design your vacuum cleaner and the repo to store all the files and allow version management.


Hiding behind the sofa

Today I cautiously stripped the wires back on my fabric cable and wired it up for real, rather nervously I crimped the spade connectors on and hooked it up. Then for a good 5 minutes I wondered around more nervous than a man outside the delivery room in a hotel. Then suddenly, I thought, bugger it! I plugged it in, turned it on and VROOOOOOOOOOOM. Then silence.

The motor turned on with such force and inertia the neutral line became unplugged. The point is that it worked, and I hadn’t been electrocuted, melted the carpet, or blown up the motor. For the few miliseconds it was on it even sounded a bit like a vacuum cleaner.

I need to build a mount for it. So much to do!

Hose cuff update

Screen Shot 2013-02-23 at 14.55.49

My work on the screw cuff is progressing well, I have been using the Ultimaker 3D printer at UCA to print some prototypes, the latest of which is very good.

The first prototype was too small but the basic principal is there:


The next few prototypes were just minor tweaks, until I added an end stop and ended up with this:

photo 2 photo 1


I’ve been trying really hard to find a vacuum hose which is both the right size (38mm ID) and aesthetically pleasing, for US viewers there is Amazon’s Industrial & Scientific section which means you can buy Flex-Tube FlexStat PU Duct Hose in a rather attractive clear with black spiral, they also sell PE screw cuffs.

However in the UK this isn’t available and realistically even if it were it would be over priced, in the UK there is a safety company called Arco, they have a couple products I am going to order 2 meter samples of, but still it’s pretty pricey.

Arcoflex Food Grade Delivery Hose Clear 5341013

Arcoflex Clear PVC Suction & Delivery Hose 5301025

OpenSCAD: Hose cuff


In case you don’t know what OpenSCAD is, it is a piece of software and a scriptiing language which allow you to programatically create 3D models for milling or printing. This is useful as you can define parameters that are user definable that actually change the way the final model renders. For example, a hose cuff needs various parameters such as, diameter, pitch, thread depth, screw length, extension, and wall thickness. These attributes contribute to the final model which can be printed and fitted to the end of a hose. By using OpenSCAD (which I am still learning) I hope that I can release a model on Thingiverse that can be 3D printed at home or through a local service bureau allowing you to use any size hose you wish for your vacuum cleaner.

This is how far I have gotten so far, but it I am having trouble with OpenSCAD’s inability to extrude a 2D surface with the plane facing along the extrusion path rather than flat on the floor, meaning there is little depth to the thread, and no control over diameter, examples included with the program seem to use a half toroid to resolve this but that seems messy.


Hoses & cuffs


Following a tutorial earlier this week with my personal tutor I am investigating alternatives to making my own hose and tool assemblies. His suggestion was that I shouldn’t stop at using just the replacement kit I bought from eSpares for Numatic (Henry) vacuum cleaners.

Personally I feel this product is the right solution as it ticks the boxes best in terms of being readily available, fairly generic and standardised and likely to be available for a long time as it fits most of their consumer products to date, it is also cheap because of this, and the off brand clone I bought is great quality. My tutor feels aesthetically it doesn’t match the standards of the rest of the unit and it doesn’t full fill the needs of users abroad who might not be able to obtain this product.

Either way I am going to prototype this, however will stop short of making my own tools as these are complex mechanisms and there is nothing to be gained from trying to make my own. I have previously stated a possible area for innovation by others would be to design new types of tools and share them back to the community, for different purposes from specific cleaning tasks to tools for workshop equipment like bandsaws, etc…

The standard hose used on most vacuum cleaners is either 32mm (1.25″) or 38mm (1.5″), some have less common dimensions. Based on this there is a decision to be made between the two, and realistically this could go either way when building your own vacuum cleaner.

The 32mm option seems the most likely candidate at first because it matches the setup I already have, it’s seemingly more common than the 38mm option, and the hose is smaller so therefore cheaper and lighter, it also matches the UK standard size for plumbing which would be a benefit.

The 38mm option however is less likely to clog from large debris and does still fit many tools, the pivotal point however on this option is that its the same type used in swimming pool cleaners which tend to be less proprietary about their spare parts which means buying odd parts like hose cuffs (ends) is relatively easy on sites such as eBay, because of this I am going to go down the route of using a 38mm hose, cuffs, and connectors, however I will be trying to use a 32mm pipe for the tools and pipes which means I will need to find a way to step down and maintain air pressure. This seems like the best hybrid, 38mm isn’t far off the 40mm standard used in UK plumbing, and in the USA is equivalent to a 1.5″ waste pipe.