Wednesday, August 3, 2011

Colour spotting in machine embroidery

It occurred to me yesterday that I needed to spend a bit of time explaining colour spotting.
Although I use it mostly in Free machine embroidery, the same technique can be used in normal feed dogs up sewing, so long as the bobbin tension can be adjusted.
 When children colour in, they tend to colour in with blocks of colour.  The sky is blue, the grass is green.  In free machine embroidery, we begin by doing this, too.  Colour spotting is a way to introduce shading and tones into machine embroidery as an artist would with paint. In the pictures above, the top circle is all one colour, the lower circle  has two colours and appears to have more substance and depth.
The principle is simple, we use a different colour in the bobbin to the top of the machine and tighten the top tension so that it draws the bobbin thread up (above).  The reason you need to be able to alter the bobbin tension is that at a certain point, you will not be able to tighten the top tension any further (the thread will begin shredding) at this point, if you need more of the bobbin showing, you will have to loosen the bobbin tension (I usually work with a bobbin that is on the loose side to start with to avoid this).
This stitch with the bobbin thread drawn up is called Whip stitch

In whip stitch, the upper tension is tight and the lower is loose and when you stitch in a straight line or a very smooth curve, the bobbin thread wraps around the upper thread.

Just to give you an idea of the subtle effect you can get with colour spotting, I made up a colour wheel for you.
In the three squares, I have used red, blue or yellow thread in both top and bottom.
Between the squares I have usd different colours in the top and bottom.
  • Between blue and yellow, the top circle had blue in the top and yellow in the bobbin.
  • Between blue and yellow, the bottom circle had yellow in the top and blue in the bobbin.
  • Between blue and red, the top circle had red in the top and blue in the bobbin.
  • Between blue and red, the bottom circle had blue in the top and red in the bobbin.
  • Between red and yellow, the top circle had red in the top and yellow in the bobbin.
  • Between red and yellow, the bottom circle had yellow in the top and red in the bobbin.
 Wow, that was a mouthful, but what I hope you have picked up is that it makes a difference for each pair of threads, which is in the top and which is on the bottom.  There are two oranges, two purples and two greeny patches.

Another important point is that dark colours, like blue show through very clearly from the bobbin, whilst light colours like yellow, are much more subtle.  If you want speckling, use a darker colour than the top thread in the bottom,  If you want a more subtle blending, choose a lighter colour in the bobbin.

Happy Stitching

4 comments:

  1. Thanks Vicki! I never used this technique, but I might in the future!

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  2. Vicki,

    What a clever idea. I've spent years trying to avoid the "pokies" now I see it looks great! I can't wait to try it.

    Ricci
    Superior Threads

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  3. I had never heard the term 'colour spotting' before. This is a great post and so informative, thanks!

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  4. Wow what a great bit of information! I'll have to try this. I do have an extra bobbin case that I can adjust the tension on so that I don't disturb the original bobbin case. Do you have an extra bobbin case too?

    ReplyDelete

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