| Lace Notes |
W i n d i n g B o b b i n s | ||||
| Introduction | Winding & Twist Direction | Making the Hitch | |||
Winding & Twist Direction
When I was fairly new to lacemaking I was told that because of the difference in twist, linen thread should be wound onto bobbins in the opposite direction to cotton thread as this would stop it breaking. However no one was able to explain to me exactly why this was so. It turns out that the way in which you wind the bobbins can have the undesirable effect of untwisting the thread or increasing its twist. This article describes a little experiment to let you see for yourself how this happens.
The S-twist and Z-twist of threads
Before starting the experiment one needs to be clear about the way that threads are twisted. Threads are usually made up of two or more single strands twisted or plied together either clockwise (S-twist) or anti-clockwise (Z-twist). If you try untwisting a few different threads you will find that most linen threads have an S-twist (twisting anti-clockwise untwists them, twisting clockwise tightens them again). Some cotton and silk threads, usually those manufactured for crochet and machine embroidery, will have a Z-twist, whereas others, particularly the finer ones, will have an S-twist.
How winding can alter the twist of the thread
For the experiment you will need some narrow ribbon — 1/8th of an inch (3 mm) wide is ideal. Ribbon is used as it easy to see if and how this becomes twisted on winding. Fasten the end of the ribbon to a large bobbin with a piece of Sellotape (Scotch tape) to keep it in place, hold the bobbin in your right hand, and start winding the ribbon on to the bobbin by turning the bobbin away from you — the ribbon winds on smoothly. Now keep the bobbin still and wind the ribbon around it instead. What happens? The ribbon twists and it is impossible to wind it on smoothly. Look at the direction of the twist on the ribbon — is it S or Z? If the ribbon is being wound clockwise round the bobbin (looking down from the top), as on the left side of the diagram below, it will have a Z-twist.
This means that winding bobbins by taking the thread round them like this, rather than by turning the bobbin towards you, adds to the twist on Z-twisted threads but take it away from S-twisted linen threads, which will start to separate into their component strands. Conversely, taking the thread round the bobbin in the opposite direction (anti-clockwise), as shown on the right in the diagram above, causes the reverse to happen and the linen thread will end up with extra twist. This is summarized in the table below. (The table is correct, even if you hold the bobbin in your left hand to wind it.)
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So if you wind bobbins by taking the thread round the bobbin rather than by turning the bobbin, it would indeed be better to wind linen thread onto bobbins in an anti-clockwise direction. However, it would be better still to try and make yourself turn the bobbin instead of taking the thread around it. Be kind to your threads and subject them to as little stress as possible — they don’t like being either untwisted or over twisted!
Winding from a reel
Even if you wind the bobbin as recommended above, you can still run into problems. This is because you will normally be winding bobbins with thread that is on a reel, and this can twist your thread! You can also show this in an experiment with the narrow ribbon, but this time you will also need an empty cotton reel. First stick the ribbon to the reel with Sellotape and then wind the ribbon onto the reel (by turning the reel). Put the reel onto a long pin stuck in your pillow and pull the ribbon from the top of the reel as you wind it onto the bobbin (by turning the bobbin). The ribbon will twist as it comes off the reel.
Wind the ribbon back onto the reel, but now support the reel on a knitting needle fixed across a cardboard box as shown in the diagram above. When you now wind the ribbon onto the bobbin it will wind on smoothly. So winding bobbins correctly is not as obvious as it may seem at first sight!