WATER is another element of the wet felting equation. As you know, water has to be added to the wool (whether in a soap/water solution or by applying it directly to the piece you want to felt).
The question is should you work with HOT or with COLD water?
I learnt to felt with hot water and I was astounded when I discovered that cold water also works. And it works because the essential thing is to create a situation of pH change in the wool, along with other conditions for the opening of the fibers. All of this happens with cold water too.
But, if you’re washing a 100% wool sweater, you know you should do it with cold rather than with hot water. And why? Well, because a higher temperature speeds up the felting process.
If you’re thinking “so why should I care?”, let me give you a practical example.
Have you ever tried nuno felting a piece with hot water, only to discover that your wool didn’t attach to the silk? This might happen for different reasons, but here’s one of them.
If you use a high temperature when nuno felting, the wool will start compacting straight away, without having enough time to attach to the fabric first.
The solution for this is to use cold water in the initial part of the process. First the fibers have to penetrate the silk, and everything has to be secured in its place. You need to give the fibers time to migrate into the fabric, before they felt onto each other. Only when you start the fulling process should you work with hot water to speed up the felting.
This isn’t as important if your project only involves wool, but if it’s a more complex piece – one where you need to work on a lot of details, like adding patterns, for example – starting with cold water could also be a good idea. Since the felting process is slower, this will give you enough time to make any corrections.
So, as a general rule, I recommend always starting with cold water and only using higher temperatures, when you go into the fulling phase. Do this, and I bet you’ll start having more control over the wet felting process.
Let me know if this helps!