Factors to consider to match up to a commercial yarn include:
- measure the wraps per inch of the commercial yarn, this gives you a guideline of how thick your yarn will need to be
- decide if you want to spin singles, 2-ply, 3-ply, or what, to get that thickness. Singles are clear – you spin that thickness that you need; 2-ply, try about 1.5 * the wraps per inch of the goal and sample to fine-tune; 3-ply, try about 2 * the wraps per inch of the goal and sample to fine-tune
- decide if drape is a factor or not – you may want to play around with how much you compact the yarn as you spin (the whole woolen vs. worsted spinning style thing …)
- decide if twist is a factor or not – is the commercial yarn high-twist (over 35-degree twist angle) or low twist (under 20-degree) or in the mid-range, and do you want to match that.
And now, for a metaphor ...
Well, all that said I usually just try to get in the ballpark and find it all works out okay in the end. But it’s helpful to know where home plate is so you can be on the field.
You were warned!!
See the earlier related post, How can I copy a commercial yarn?
Some recent matching/copying work shown in the pictures in this post, Icelandic low-twist 2-ply, blogged here.
My most recent copying attempt, laceweight Merino singles, on flickr.