Thursday 6 September 2012

Etch-a-Sketch at the Brighton Mini Maker Faire!


I’m demonstrating electrolytic etching at the Mini MakerFaire on 8th September at the Brighton Corn Exchange and had a fun day yesterday experimenting a little.

First, an introduction to the Mini Maker Faire. Last year we happened to come across this wonderful event walking through the North Laines in Brighton. There were ‘makes’ of all sorts and sizes, from tech gadgets to traditional crafts. Have a look at this year’s makers for a taste of what you can experience. It’s for kids young and old, so make sure to come along this year! It’s expanded considerably since last year – Rob (my other half) is showing his Xylophone-playing robotic arm and other toys, and fellow maker Emily Wright of Cuttlefishlove is running her very popular Kanzashi-making workshop for a second year! 

My contribution will be your chance to “Etch-a-sketch” on copper. It’s incredibly easy and is the perfect home science experiment! With a few precautions of course! What you need:

·         2 pieces of clean copper; I use a wire brush to buff them slightly and some Gariflex (you could use a bit of very fine ‘wet and dry’ paper) 
·         Power supply 
·         Electrical wire 
·         Wire cutter 
·         Crocodile clips 
·         Small plastic tub 
·         Table salt 
·         Hot water 
·         Wooden stirrer 
·         Gaffer tape (waterproof adhesive tape) 
·         Selection of possibilities for making your sketch (see below)
    and this is what you do:
    1. Boil some hot water and dissolve salt into the water with a stirrer. Keep adding salt till you can no longer dissolve any more into the solution.
    2. Attach the wires to the battery and attach the negative of the battery to a piece of scrap copper using a crocodile clip (see my setup below).
    3. Attach the positive from the battery to the piece of copper to be etched: Expose the wire by cutting through the plastic sheath and attach that directly onto the back of the copper piece with Gaffer tape (see photo). Ensure that all areas you don’t want to be etched are covered very well by Gaffer tape and that it’s water-tight as far as possible. You can cover difficult areas using a permanent marker pen.
    4. Ensure both pieces are submerged in the salt solution.
    5. Turn on the power supply and watch it fizz away! Generally a good etch can be obtained in 20 – 25 minutes. The timing of course is dependent on the thickness of your piece of copper and how deep an etch you want. 
     
    Piece of copper prepared to be etched using a water-proof sticker

     
    Etching set up


    Possibilities for your sketch are endless. Any exposed areas of the copper will be etched therefore your ‘sketch’ results from a resist which protects some areas with a thick water-proof covering which is left untouched: 
    ·         You can use waterproof stickers (or masking tape and cut out your designs). 
    ·         You can use permanent maker pens – just make sure to lay it on thick with the marker because if the marker dissolves, the etching will bite into the areas you don’t want etched. 
    ·         You can also use stop out varnish to get a really effective etching – paint on the varnish and then after some time scratch in the design you want. Getting varnish off however, is not the easiest task so you will need to use some white spirit to remove it.

    The results; top piece was etched using a marker pen; the bottom pieces used stickers/cut-outs glued onto the copper

    So, want to try it out with me and learn some of the science behind the process? Come see me and other makers at the Brighton Mini Maker Faire!

    1 comment:

    1. Wow! That's some tutorial! You are some kind of science wizard :D Good work and thanks so much for sharing it!

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