If your not very good at it.
All last week I spun lace and because I'm not great at lace yet it took a very very long time (this blog has also been waiting its turn for a week because it needed a photo).
Usually I can spin 8 oz of 2 ply fingerling weight in about a day, but since I'm just starting to learn to spin lace I'm going slow to try and get enough twist. Many spinners have shared with me that they have a chronic problem with not having enough twist in their yarns and it makes it easier to break a single when plying if this happens. So my approach has always been to make sure that I have some extra twist in my yarn and so far its been a success.
Problem with putting that extra twist in lace is that it tends to break the single because I don't have enough fiber and its trying to pull into my bobbin too fast.
Now there are two ways to fix this. First is that I can use a fiber with a longer staple so I'm currently hunting down a good silk or milk protein fiber in colors that would look good on my mom (this is actually more of a chore then it sounds because its got to be a color she likes and one that I'm willing to look at long enough to spin and knit... so I'm limited). Second is that my wonderful Little Peggy was built by the very clever John Rappard and he made it so that it has the springs and holes drilled to be used with a scotch tension knob. I use it with a double drive band, as that is how it came to me, but if I keep having trouble its nice to know I can switch.
Till then enjoy this picture of bright green singles that will become a shawl I'm designing for the booklet in November