The amount of wool top, or roving you need to buy will depend of several things; size, shrinkage, details and techniques involved. To give you examples of calculations I have chosen the Merino wool I supply at www.SarasTextureCrafts.com
The best thing to do if you haven't made a bag before is to buy a book and follow the instructions. It is a simple process, but following someone-else's recipe will give you a great starting point for your own future creations.
In this particular project's case I recommend the book (press the link below to purchase via Amazon);
Complete Feltmaking: Easy Techniques and 25 Great Projects (Complete Craft Series)
By Gillian Harris
The cover project is a bag measuring approx. 20x30cm (8x12 inches) and requires about 300g-400g of Merino.
I hope the above information has given you some idea?
My solid Merino colours are always restocked, so if you find you should need more, just give me a shout and I can let you know where to find it. I also have a Merino colour card in my shop which might help you pick your colour options.
Have a wonderful day... Sara x
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