Using Heavy Bikes as an Advantage

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Using Heavy Bikes as an Advantage

If you work on multiple bikes using any sort of bikestand, it may have gone something like this:

  1. Wheel bike up to stand. Ascertain whether you want to clamp the seat post or the top tube
  2. Fiddle with preload screw on stand until you think it will close down to around the right diameter for the chosen tube.
  3. Heave up bike awkwardly, trying to squeeze it into the jaws of the stand. If on the seattube, remove one hand and desperately try to do up clamp (top tube can be slightly easier.)
  4. After the sense of panic has subdued, re-adjust slightly and start working on bike.

Having worked on lots of older bikes (read: heavy with standard tube profiles) I thought it might be fun to see if I could devise a way to change the 2 handed clamping process often necessary. What if i could make a way of holding the bike still that used the weight of the bike itself to secure it in place?

Reading a Core77 article, I stumbled across a ingenious mechanism that could accomplish just this being used in a everyday hook: http://www.core77.com/posts/26206/linden-swedens-clever-hook-design-26206

I used this as the starting point to create the profile of a similar mechanism. In essence, once weight is placed on the lower part of the hook it pivots, and drives the top part down using a cam-like interface between the two. Initially, the shape of the mating surfaces needed work:

However, after refining the curves, and adding a number of different profiles to share the load, I was able to make something that opened and closed reliably. 

When testing this on my limited range of bikes, it proved very useful- the clamp securely held the top tube, and immediately released the bikes when I lifted them slightly out of the stand (fortuitously they all had very similar tube diameters).

Please ignore the obnoxious whistling!

Perhaps this isn't the best application when there is such a variance in bicycle top tube diameters (and shapes, given today's crazy hydro formed aluminium and carbon profiles). Any ideas for other uses? 

 

 

 

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Seat Ibiza 'Camper'

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Seat Ibiza 'Camper'

Whilst browsing the net, I came across a picture of a stunning coastal road. After further research, It turned out to be a section of the Northcoast 500- a series of roads that wind their way around the coastline of Northern Scotland. Given Scotland's liberal approach to camping, this seemed like the perfect destination for a multi day roadtrip. 

However, looking at vans that would be suitable for a camper conversion and a practical daily driver was disheartening- they were all vastly expensive, with insurance to match. Thus, I decided I would look for a practical car to use to commute to my new job, that I could also modify to sleep in. 

At a used car showroom I stumbled across a 1999 Seat Ibiza with remarkably low mileage, full documentation, and that was surprisingly spacious once the front seats were folded forward. After handing 500 pounds over, I drove off in my first car. 

After a full service and a good clean, Hamish (a name recommended to us by a friendly Scotsman) was ready to be made fit for a week long roadtrip with 2 people. I started by procuring some materials for the build- I was living next to a construction site at the time and the contractors were more than happy for me to take some pallets and random bits of timber off their hands. 

The initial inklings of the bed frame

The initial inklings of the bed frame

I started by removing the rear seats, and then bolted a box like frame directly to the chassis using the seat fixings. This would form the latter half of the bed platform, and also offer the largest storage space beneath it. 

Stripping down the slats on a number of pallets, I then joined them together with some struts. Once finished, these sat on top of the box structure which the mattress would be laid on. I made the whole panel fairly easy to remove, so that we could easily get at the storage space underneath. 

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Next, I made the front platform for the bed- this would have to self supported at one end so that all the weight wasn't placed on the back of the front seats. This consisted of a number of slats with 2 struts underneath that had pivoting legs that rested on the floor of the car, supporting the front section. The rear had a crude lap joint with the box structure in the rear, and slotted into place with 2 pins ensuring that it didn't move. 

After checking it all fit together snugly, I removed everything, and sanded down the grubby faces of the pallet wood.

It was necessary to create some sort of mattress. Initially I found some very thick, comfortable foam that I was able to cut to size. However, this took up allot of room in the car, and so I opted for a thin 'self inflating' camping mattress- although I could stretch out fully, it didn't leave much head room in the car for manoeuvring around. This meant there was way more head room in the car, and also that when the bed was 'put away', it took up significantly less space.

As we would be sleeping in the car, it was essential to create some way of blacking out the windows- stopping people from peeking in and providing us with a dark sleeping environment. I purchased some black fabric and cut it slightly oversized for all of the windows. I then stapled on some cardboard tabs that allowed it to be snugly pushed into the gap between window and liner, affixing them in place. Where this wasn't possible I used some small button cell magnets to 'clamp' the fabric to the bodywork of the car. 

A rough walkaround of the car set up in 'Bed Mode'

As mentioned earlier, the negative space underneath the bed platform acted as storage for all of our essentials- this was divided up into a number of boxes for toiletries, kitchen and cooking implements, bedding and the like. 

And just like that, it was time to go! 

Thoughts for next time:

  • By adding a second set of pivoting legs to the front bed section, it could become a free standing table once removed from the car at any 'camp site'.
  • Although side curtains worked well, we would often wake up to find that the material had fallen away from the sides of the windscreen. Perhaps having an internal wire frame or using suction cups on the windscreen could be better.
  • Modifying the boot of the car so it could be opened from the inside would be useful for those morning vistas
  • Could a net be strung internally, acting as like a large hammock and negating the need for a bed platform entirely? this would fold down to be a very compact size, and leave much more room in the car for other camping essentials (aka mountain bikes). Equally if the bed platform was split down the middle, I could leave one side permanently in place for any solo mountain biking adventures, and stow my bike in the other side. 
  • You definitely don't need a T5 camper to have an amazing time!

 

 

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Rethinking Bike Boxes

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Rethinking Bike Boxes

If you've ever decided to take your bicycle on a flight, chances are you have purchased and crammed your prize possession into a bicycle specific bag or box of some sort. Having used several of these myself to cart my bike around numerous times, I've always been petrified that my 2 wheeled friend will be damaged in transit, spending the entirety of my journey squirming in my seat and wondering what I'll find on the other side. 

Currently, the internal layout of most bike bags is very similar- take both wheels off, remove/ drop the seatpost, turn the bars and then place within the bag, often with dedicated sections for the wheels. Although this is fairly straightforward, it results in a very long and cumbersome form factor. Higher end bags will have some sort of internal structure to stiffen up the bag, protecting the bike and making it easier to manoeuvre, although due to the length of the bag and the relatively high centre of gravity they are very difficult to wheel around with ease- prone to toppling over and putting most of the weight in the owners hand (if they even have wheels). Lets just say you're not the most popular person on the train on the way to the airport with one of these bags- and don't even think about booking a regular sized cab.

The idea for this simple re-design in form factor came with the realisation that most modern full suspension mountain bike frames are actually formed of several smaller structures- due to having rear suspension inherently the front and rear triangles of the frame are split. By splitting the frame into its respective components, a much more compact full bike size can be achieved- often all this necessitates is the removal of 4 pivot bolts for the rear seat and chainstay assembly. 

This results in a full bike size that is much more manageable, and thus results in a bike box with a significantly smaller size. By virtue of the shape of the box, the centre of gravity is directly over the rear wheel when the box is lifted by the handle- very little effort is required to manoeuvre the box or hold the handle aloft when in this position. The shape of the box is much more friendly to cars- I was able to fit my full suspension bike and kit in the back of a Nissan Micra with ease!

Internally the box is divided into different sections with a series of foam dividers. The wheels sit on the outside, and rest against internal struts in such a way that the rotors are protected from any impacts (so they don't have to be removed from the hubs whilst in transit.)

Having just used the setup to transport my bike on a seven and a half hour international flight, my bike arrived completely unscathed, and was a joy to wheel around Gatwick airport. 

Obviously this is a very rough prototype, but has shown that there is definite scope here for a more resolved design. 

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Adventures with Plastic; Part One

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Adventures with Plastic; Part One

Look around you. I almost guarantee that wherever you are, you will be able to identify at least three objects that are solely made of, or contain plastics. This isn't even including the device you're reading this on.

This amazingly versatile material has become invaluable to our society. From packaging the things we eat, to the things we commute in, it's everywhere. Unfortunately, disposing of plastic once its served it's purpose is never easy.  

Keen to experiment with the properties of these materials in a more hands on way, I cruised down to the local charity shop to see what I could find. When I returned home later that day, I was the proud owner of a dedicated desktop cupcake oven, 2 hotplates, and a shredder.

My initial idea was to hack these together with a few other basic elements to create a plastic extruder- think 3doodler but much more messy.  However, I started experimenting with the equipment in it's current form.

HDPE is a readily available, easy recyclable thermoplastic, and is what milk bottles and tops are currently produced from. It can be moulded at relatively low temperatures, with few toxic fumes. This seemed like an excellent starting point.

What followed was a series of experiments, to see how I could manipulate the material. I started by cutting it down into small pieces by hand, so that it could fit into the individual 'pods' in the cupcake maker.

 

It was possible to take a handful of HDPE scraps, and then melt them down to a putty like consistency, which can be formed by hand (with gloves!) I experimenting by making up some rudimentary moulds, and compression moulded a few basic objects;

The best part about working with plastic is if your not happy with the end result, simply melt it down and reuse! This can be done several times before the quality of the plastic degrades. The final material is stable, strong and durable, and can easily be worked with common woodworking tools.

Next up is looking at common shopping bags.

 

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To the spare room!

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To the spare room!

After finally receiving some copper tape in the mail, the spare room got a makeover;

It's also worth noting at this point the safety issues of this project. Please please don't try this unless you are fully comfortable with the wiring of the circuit, and have the proper equipment. The capacitative system is completely safe, as no power is routed through the strip that circumvents the room (think touch lamps), but mis-wiring could potentially result in exposed live components. All the chocolate blocks I've used for this project are appropriately rated, and have been stress relieved with cable ties. Ideally I need to then heat shrink over the chocolate blocks, as mains voltage is not something to play with. 

The next steps are to look further at proper room integration, and striking a fine line between a visible light switch & a visually unobtrusive solution. Concepts need to made for the design of the switch that will be embedded in the wall- the aim is to design a hub as it were that would fit in the wall space of a conventional light switch. Further to that, I need to look at the power consumption- it may turn out that this is incredibly energy in-efficient.

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In the hot seat

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In the hot seat

About a year and a half ago, someone explained the principle underlying how a peltier tile works to me. If your unaware of these amazing little gizmos, they essentially have the power to create a heat difference; connect the tile to a power source, heat one side, and the other side will cool. Conversely, chuck an ice cube on one side, and the other side will get hot. They're often used in small mini fridges like the one you might have had in a student dorm, and rely on the warm ambient temperature on one side to chill the interior of the fridge on the other.

This ability to create a temperature difference can also be exploited in another way; if you create the temperature difference yourself, the tile can generate power. I first saw this in the following youtube video, and was baffled at how efficient it can be.

The major issue with generating power through peltier tiles is that without something to constantly apply an inverse temperature to the other side, the heat will diffuse through the device, and as a temperature difference no longer exists, no power is generated. Because of this, peltiers often feature a large heatsink on one side to cool it as quickly as possible. 

I commute year round via bicycle, and in the UK this means spending a great deal of time in the dark. I've got an excellent set of lights that I use for both mountain biking and commuter duties, but remembering to keep them charged is a pain, as well as continually checking the rear of my bike as I'm riding along to ensure that my rear blinker hasn't run out of juice.

I realised that if I planted a peltier tile into my seat, I could harness the thermal energy produced from my body, and rely on the air rushing underneath the seat to cool the other side of the peltier tile. The current put out by a peltier is very small, so I ordered an ultra low voltage converter to transform it into something that could power 2 small red LED's. 

I then set about hacking an old seat to pieces. I managed to find something that was wide enough to accommodate 2 peltiers side by side. These were inserted into the seat, along with an aluminium backing plate (having ceramic outer plates for good thermal conductivity, peltiers are very delicate) and an old aluminium heatsink that I bent into shape.

The end result was a very rough principle proving prototype of the system. I set my trusty commuter up on a turbo trainer, and put the saddle on the bike. I then start down and sat pedalling. After a few seconds, the LED's began to glow, and continued to do so as I stayed seated.

The addition of a small capacitor in the circuit would mean that the LED's could stay lit for a minute or so after getting of the saddle, for long efforts standing up or waiting at traffic lights.

Although perhaps not a feasible commercial product due to much more efficient dynamo's, I enjoyed playing around and am considering taking the project further. Expect a line of thermally conductive lycra soon!

 

 

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Fun with conductive paint

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Fun with conductive paint

Taking a very quick look to see whether electrically conductive paint could be integrated into a capacitive light system. (*SPOILER* contains the cheesiest tune known to mankind.)



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Turning the Pedal Upside Down

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Turning the Pedal Upside Down

If you know me at all, you'll know that I love to ride bikes, and have far more than is considered healthy.

My Housemate and I were pushing our bikes up a local Downhill trail, struggling to get grip whilst continually bashing our shins and the backs of our legs on our incredibly spiky pedals. I have a set of DMR Vaults on my bike that I absolutely love due to the grip they provide. However, when this grip is applied to my lower legs, it's not so nice... (type pedal bite into google images if you're sadistic.) BMX riders actually opt for plastic pedals, due to the much less painful contact. 

The thought occurred to us that perhaps if the pins were transferred to the bottom of the shoe, and the pedals had a layer of rubber, it could alleviate/ improve several issues;

  1. Increased grip on the trail when off the bike (due to essentially having hiking cramp-ons)
  2. No Shin destroying pins to smash into when your foot slips, or when pushing the bike.
  3. Increased pedalling efficiency due to having a stiffer sole on the shoe.
  4. Longer system life- the only component regularly needing replacing being the rubber pad on the pedal ( as opposed to buying a new set of shoes once the soles are worn down.

I managed to rustle a few parts together in the workshop, and set about making a rudimentary prototype of the system that I could take to the trails. I stuck together a quick video to highlight the process. 

 

Currently the sole consists of an external aluminium plate spanning the entire length of the shoe. This will have to change, to find a good compromise between sole flex and walking comfort (you'll notice in the small amount of testing in the video that my gait is rather unusual). In production, this could easily become an over moulded part, integral to the sole of the shoe.

I then kept one of my incredibly rough prototype pedals on one crank arm, and replaced the other with one of my original pedals, the DMR vault. Although the pedal height was very different, I was surprised by the similar level of grip.

The next step is to use a rubber/ elastomer pedal pad, mocked up on both sides of the pedals so that they are equally weighted (it was very annoying having to spin the unevenly weighted pedal around each time), stick it on the downhill bike and take it to some proper trails!

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First Post- Inexpensive Touch Lighting

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First Post- Inexpensive Touch Lighting

Hi All,

I thought I would start with a project that is in it's very early days, but that I think shows promise for a commercial idea. I'll let the rough, one take video speak for itself!

I'll be aiming to post about new ideas and developments at least once a week. Thanks for watching!

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