Old patterns and incomprehensible needle/thread sizes
Marie asked about some of the needle sizes listed on old patterns. In particular, she wrote, "I've never heard of size 14 knitting needles."
One of the interesting things about old doily patterns are the needle sizes and threads they call for. They often do not correspond to modern American sizes or the modern millimeter size standards.
Here is a chart listing old English, American, and millimeter equivalents.
In general, for the old English sizes, the English size plus the American size will equal 14. So, subtract the English size from 14 to get the American size. Size 14 knitting needles will be an modern American size #0, or a 2mm needle.
This isn't fool-proof, but it gets you in the right area. The English sizing system will show up in patterns published in the UK, from Canada, Australia, New Zealand, etc. The old US dpn sizing system is similar to the old UK system, but not exactly. (Please don't run away screaming!) Marianne Kinzel says that the UK 14 is equivalent to a US 13 steel dpn, and that the UK 13 is a US 12 in dpn's and either a 1 or 2 in US circular sizes (I can't remember offhand, though there may not be an exact equivalent US circular size).
This Wikipedia article lists Japanese sizes as well as the US/UK/metric sizes.
Some old foreign-language patterns use needle sizes that I haven't figured out at all. What is a 2/0, for example? Is it 2mm? #00? Something totally different? What if the only needle size given is "a set of brass needles"? If the thread recommended is something like "fine crochet thread", that doesn't really give any further hints.
For some of the old German needle sizes, Catherine Kehr posted the following to a mailing list: "Ages ago I asked someone about the N/0 sizing, they said it was an old wire gauge system, that 0/0 would be .5mm and 8/0 would be around 2.5mm." She was interested in getting more information about it, so don't assume any of us know what we're talking about!
I should look through some of my older stuff in French, Italian, and Spanish to see how they approach matters. The publisher and the age of the publication all seem to have an effect on what terminology is used for needle size.
Since the title of this post is "a short discourse..." I will not continue further. It's an interesting topic, though. I'll look through my pattern collection and report on the results. It will be a limited sample set, though. I don't have a lot of really old doily patterns (pre-WWI), and I don't have a lot of old, foreign-language, non-doily patterns. I haven't been able to find anything online or in the library that includes a detailed history of knitting needle sizes in different countries and different eras.
How to deal with old patterns' needle and thread sizes
The way I deal with it is: I ignore them.
Some threads available today are pretty much the same as the ones called for in old patterns. Some aren't. Also, sometimes I'm not in the mood to do a large doily in thread thinner than sewing thread. Maybe I want to turn a pattern into a shawl, or I'd rather use a particular thread that isn't the same as a pattern. Or I don't know what thread is meant by the description.
The other big factor is personal. How tight or loose do you knit? How gauzy or solid do you like your lace to be? Those have such a huge influence on how you match the thread and needle size.
It can vary, too. In fine thread, maybe you want a very gauzy piece. If you were to do the same pattern as a shawl or an area rug, you might want a much firmer fabric, with the holes correspondingly smaller to minimize snagging.
So. What do you do? You experiment.
When I first started out knitting doilies, I picked a small 24-round pattern. I knit it several times. First, I used the same thread but changed needle sizes. Then, I did something similar with different thread sizes. After a while, you start understanding what needle size you need to use to get the kind of lace fabric you like with different thread weights.
As I continued knitting, I gained yet more experience. Sometimes I thought a doily was too tight or too gauzy, and would use that information the next time. Sometimes I would deliberately try something different, and thus would learn something I hadn't previously known.
Now that I have plenty of experience, I have a pretty good idea about which needle/thread combos I like and don't like. I still experiment and still continue to learn.
One really great thing about lace knitting is that it tends to look wonderful at a whole lot of different gauges and fabric densities.
If you've never done it before
If you are totally new to doily knitting, you can try using the pattern's recommendations (if you can figure them out). Or, you can ask others for recommendations. This only works if your knitting style is similar to the style of the people giving the recommendations.
In general, you want to choose a needle that is a few sizes larger than what you would use for stockinette. Most knitters already knit with yarn, so that makes it easy to select an appropriate needle size for the first round of swatching. If you don't knit with thread, though, it can be harder to make that initial choice.
I am a very loose knitter, so my usual choices are too small for most people.
I looked at the thread and needle choices different people mentioned for the BlätterspitzenKAL. Thread sizes ranged from #10 to #80. (No one chose to do it in thick yarn for use as an area rug.) Needle sizes ranged from 1.5mm to about 3mm. The larger threads tended to use the larger needles, but it wasn't perfectly consistent. So that might give you a place to start.
If you're using #10 crochet thread, try a 2mm needle if you're a very loose knitter, anything from 2.5mm to 3.5mm if you're a more average or a tight knitter. For #20 thread, the range I see is 2mm to 2.75mm. For #30, 2mm to 2.5mm were the sizes mentioned, though I've used 1.5mm with good results. Even the #80 thread was worked with 2mm, to give a very open fabric.
Until recently, no one made #00 (1.75mm) circular needles. So, you won't see that choice mentioned very often. Now that a few manufacturers make them, you'll start to see them being used.
You can, of course, do a rough block on your doily when it's only partway done. You can evaluate your needle/thread combo to see if you like the contrast between the open and solid parts of the lace. If you like it, keep going. If you don't like it, adjust your needle size accordingly. You can either rip and re-do, or change needle sizes at that point and keep going. Use your judgment to decide which to do.
Some people deliberately change needle sizes as they knit the doily. Some will do the center in smaller needles, then shift upward about 1/4 of the way through the doily. Some will change needle sizes at potential problem areas, where the motifs arrangements shift dramatically. Others systematically go up several times, looking for that "more-than-circular" effect popularized in the XRX Knitters Best of Shawls and Scarves book.
Some old patterns do not have a regular increase pattern. The number of stitches per round can vary quite wildly. This can create binding issues when you block the item. Some of us have speculated that the very fine threads and loose gauges of the past helped to compensate for this problem.
Other patterns have zillions of stitches per round, way more than seems necessary. Again, getting the finished item to block flat can be a problem. My speculation on this issue is that it's a way to get loose, gauzy fabrics to look more solid in areas where they're supposed to be solid. It's probably more of an issue with the modern preferences for thicker threads and more solid fabrics. There are a couple of other possibilities for why some patterns have so freaking many stitches per round, but I won't go into my other speculations for now.
A third potential complication is if you're knitting a shawl. When I use a thicker yarn, I tend to want a more substantial fabric. I want the holes to be smaller in comparison to the rest of the pattern, and I want the solid areas to look relatively solid. I like drapy fabrics, but I don't want to put a huge amount of effort into something that will snag on the first wearing. So I tend to choose a relatively smaller needle for the lace than I would if it were done in thread. This can exacerbate potential binding issues. So, when I knit a shawl, I try to minimize potential difficulties by choosing patterns that I think will work well. I'll probably babble on about that topic in some future blog post.
Is everyone asleep now?
Here's a photo of that first doily pattern I knit. It's the Rose Petal coaster pattern in the Coats Dazzling Doilies to Knit booklet, which goes in and out of print. The doily is something like 24 rounds. The patterns are given in text only, but no one has ever reported any errors. There are roughly 8-10 patterns in the booklet, ranging from 24 to 130-ish rounds.
I don't remember when I knit this particular version of the doily. I don't know what thread and needle size I used, though my guess would be either #10 or #20 thread and 2mm needles. It's a cute little thing, very quick and easy. It's a good pattern for a beginning doily knitter.
At some point, I'll do my standard discourse on good choices for beginning doily knitters. But not today.