Introduction: See Through Contour Map
Teaching children how to use a magnetic compass and how to read and interpret a map is still an important skill. A modern smart phone will take the user to most places with its GPS. A smart phone will not however teach the user much about the geography of their local area, or how man has used or worked with it over hundreds of years.
Part of map studies is discussing contour lines and what they are about and how they can effect our movement across terrain and how they can help us to understand where we live. A paper map with lines on it does the job but I needed to bring it to life, I decided that I would try to make an overlay in clear plastic and make it 3D using a vacuum former.
Vacuum former ( I made my own... must do an instructable about it some day)
Sheets of 5mm MDF
Fine sand paper
Sheets of clear 0.5mm PET
A contour map to work from
Step 1: The Buck Starts Here
First thing to do was to print off a map of the required area to a size that would fit on the vacuum plate of the former.
I then decided on the height scale, I went for 5mm for every 50m change in height. I ran off a number of copies of the map and began cutting out templates starting from my lowest level and transferring the shapes onto the MDF.
This was then cut out on my scroll saw and layer by layer it was assembled using clamps and PVA glue to form what is called "the buck".
Step 2: The Buck Stops Here
Once all the layers were assembled and the glue was dry I used fine sand paper to round off all the edges of all the layers to help the release of the formed plastic.
To ensure that the air could all be sucked from around the buck I glued a number of pieces of thin card to the underside
Step 3: ..... It Sucks!
Very briefly the vacuum former has a heater at the top, the plastic sheet clamps between two frames and is raised to just under the heater where it will get soft and saggy, the buck sits on the bottom plate of the former which has holes in it. Underneath this is a vacuum cleaner motor. When the plastic sheet is nice and soft it is lowers over the buck and the vacuum is turned on.... at this point it all gets a bit fraught and I needed to concentrate so no video of the contour map being formed, I had 10 sheets of PET and needed 10 contour maps.
I have however uploaded a video I had Mrs Rog film of me using a different buck to show how it works.
A word of warning, the last part of the video is VERY LOUD!
Step 4: All Done, Let's Use It!
I need to say at this point that I am in the UK, the mapping sessions are part of the Key stage 2 geography syllabus, age wise it is the equivalent of Grades 6 to 8 in the USA.
The children need to look at the basic map and work out why the major roads are routed where they are and why the local village is where it is, not too obvious until the map is viewed through the 3D overlay. It then becomes easy to see that the roads go through the gaps in the hills or take the less steep route to the top of a hill. That the local village is on a series of plateaus raised above the valley bottom above the nearby water course. It can also be seen that the church is at the highest point of the village where its spire can be seen from miles around. ( a scale model church perched on the 3D overlay then viewed from a low angle help to emphasise the point.
Participated in the