Bridging The Gap! How Using Simple Meccano Can Lead To A Greater Understanding
Have you ever picked up a ‘Lego Block’ or a ‘Meccano Part’ and thought “What a childish toy?”
Or
Have you thought “Wow I could build Tower or a Bridge with that!”
A Quick Rant
Well it is funny I only seemed to find these “2 Types” of people in many different capacity’s, by that I mean ‘people who just see something for what it is,’ And ‘people that have strong imagination whatever the resources presented in front of them.’ Well I fall into the second category as I have great imagination and ideas as you will have seen from my website projects already, but it is starting to become more evident that the younger generation is falling into the first category. Agree or Disagree with me but I have seen first hand that the majority of our younger generation is starting to lose their independent learning skills, where their learning capacity is restricted by feeding them the answers to get them to pass a test.
It Is my opinion that you could sit 30 children down in a classroom, and hand them a pen and paper and tell them “Just Draw Anything.” And that 29 children would put there hand up and ask “What do you want me to draw?” Instead of getting the desired result of 30 unique drawings on 30 different pieces of paper.
Ask most of the younger generation what they do on a day to day basis in their free time (when not at school) and you will more than likely get the response of “I play my games console” and “I talk to my mates on the internet,” well when I was younger I spent most of my time in the local woods building base’s, playing man hunt and trying to work out how we can build a bigger tree house in a taller tree. Even though most of my time was spent out doors, expanding my mind and asking why?
”The important thing is not to stop questioning.” – Albert Einstein
The Idea To Create Something
Well I had been offered some Meccano for nothing as it was going to be thrown out and I had to take it, as my love for technical building toys is strong. And now that I have a full small toolbox full of Meccano what do I build? The possibilities are endless with such a brilliant product. So I pondered for a while and after watching a Discovery channel program about building Bridges (Extreme Engineering) my mind was set.
How To Challenge Myself
Well building a bridge out of Meccano is fine, but how can I make it a challenge? So off to my workshop to build a platform to mount this bridge I was going to build on. All I did was pick out 3 bits of scrap chipboard to make an imaginary Gap or Span that would give me a bit of a challenge. I did not measure the gap of this base to make sure I used my mind to Bridge The Gap.
On With The Planning
Well the objective is set ‘To build a bridge out of Meccano,that would span the Gap that I had made out of scrap wood.” So the first thing to do was to brake down and sort all the Meccano parts I had so that laid out a rough idea of how I could go about building the bridge. Well with the parts layout out in front of me time to make a decision what type of bridge?
Types Of Bridges
As you will know and have seen there are many types of bridges, but what types could I use? Here are some examples in the picture below.
But Seen as I am using Meccano in this build there has to be cogs and moving parts involved in this build (just not a Meccano build if I don’t) so it calls for an opening bridge span or two, and given the fact that the sides of the gap are only about 12mm high it would make sense ‘if an imaginary boats wanted to go under’ (See what I am doing yet, actually thinking about what I am building and reasons behind it!) So a mechanical draw bridge it is then…
As you can see an example of a working mechanical draw bridge in the real world
One of the most famous mechanical draw bridges I know of has to be Tower Bridge in London, having been across Tower Bridge on numerous occasions by foot or taxi, it always marvels me the amount of engineering and construction that has to have gone into it. Not to mention the inspiration to build such a bridge, really could you just wake up one day and say “I am going to build a bridge like no one has seen before”? Well yes you can! and Tower Bridge stands to day as testament to that ideal.
But even though this is a thought I like to believe entirely, I still must point out with most projects there are constraints and conditions to designing and constructing such a build. The main constraint of Tower Bridge was that the Thames could not be shut and boats had to pass under it through out the construction. Also the Draw Bridges must be fast, as most drawbridges of that size in the period of which Tower Bridge built would take over an hour to raise. Also the main source of power was low pressure steam engines, so the need for a counter balance system was thought up in the construction. If you wish to find out more about Tower Bridge go to the bridge’s web site here http://www.towerbridge.org.uk/
The First Side
Well now that I know the sort of direction in which I will construct my own bridge, onto building the first side. A lot of thought and trial and error went into constructing the mechanical workings for the first side, as I had only a couple of cog sizes to work with (e.g. A Small Size and A Big Size) so you can see from the picture I finally found the right gear ratio for the first side of the bridge to open and close smoothly, this side of the bridge is connected by direct drive through the cogs from the gear housing.
First constructed side of the bridge
The Gear House
Well it was clear after building the first half, that I would need to create a way of connecting the first half to the second half, but what method should I use? At first I thought of a Shaft System using rods to connect one side to the other. Which would have been the optimal way of making the two half’s work in tandem. But I did not have enough rods to make this a viable solution, so I had to think up another way of raising and lowering the second side. So I opted for string spanning over the gap and connecting the two half’s. So this presented another issue as I had to add another set of cogs to the gear house to accommodate the string winder.
The Gear Housing From Above
So the gearing is layout as follows..
(I have listed the shafts starting from the winding handle as 1)
- Winding handle > small cog
- Small cog > worm screw.
- Large cog
- Small cog > large cog
- Small cog – String Winder
- Large Cog > First Half of Bridge
Hopefully you can all follow that?
The Second side
Well now that I know I will be connecting the second side from the first by the means of string, how should I make it work? Again we have a couple of options to choose from? This is a concept that would be effected by Newton’s Laws of Gravity or Newton’s laws of motion ’Action and Reaction.’ So knowing these points what I could do is, ‘use a spring to push the second half of the bridge open,’ and then when I turn the winding handle on the gear housing it would shut the second half of my bridge. Or the option I went for having the bridge on a Counter Balance System, so the weight of the second half of the bridge would be offset by a Counter Balance Weight connected to the other end of a pivoting point of the the whole assembly. So when the winding handle is turned the string would pull the Counter Balance Weight upwards, and in turn the second side of this assembly of the drawbridge spanning over the gap would lower in to position.
The Counter weight made up of spare Meccano parts, e.g. worm screws, etc…
Looking At The Bridge
Well Looking at the bridge as a whole, I feel quite a scene of self-achievement as I have not built a base to fit a toy. I have “Engineered a Mechanical Drawbridge to span a undetermined gap.” As simple as this little project has been what I have achieved here is what engineers do everyday to keep the civilised world running. As everyday bridges of all shapes and sizes are used by Cars, Lorries, Trains and by people on Foot, to cross gaps and spans that could not have be crossed if the bridge was not there.
But really no matter how small or big a bridge you build, and no matter what materials you use to build it. The amount of Planning, Design, Trial & Error, Research and Imagination that goes into it is still a considerable amount. Just taking this little project I have created here, it has got me researching types of bridges, it has got me looking back at the history of “Tower Bridge,” it has got me thinking “how do I configure the gear ratios correctly,” it has got me engineering a way to work both sides at the same time “The String connecting the two halfs,” and it has been great fun with a sense of self-satisfaction at the end.
To Conclude
So next time you look at a Lego block or a Meccano Part don’t dismiss it as a child’s toy, embrace it as a Start or Building Block to a greater project. Because if I had looked at it in the way of a “child’s toy” I would have never have had a Greater Understanding of…
- Different Types of Bridges
- Tower Bridge, How and Why it was built
- Gears and Cogs
- Gear Ratio’s
- The Planning it takes to Build A Bridge
- Newton’s Laws of Gravity
- Newton’s laws of motion
- Counter Balancing A Structure
- Thinking Out Side The Box
The only way we as humans learn is by Making Mistakes but if we don’t try to better ourself’s we will never Learn. There are so many different ways I could have “Bridged That Gap” Bigger, Better, Faster, Stronger, but I have a greater Understanding of that now because I gave it ago. There are many different types of Model Engineering that are regarded as Only Child’s Toys such as Model Railway Layouts, Model Planes, Remote Controlled Boats and Cars, but they tend to have so much skill and engneering to them that they becomes more than just a toy.
The Meccano I Had left after the build
But I guess all that is left to do is dismantle this bridge and make some thing else
“for it is Meccano after all”
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