Yarn Sub Conversion Factor – on the belly band of the yarn. A post with far too many rhetorical questions

So you’ve found a wonderful pattern, it’s got several projects up by different people, so you are pretty sure it’s well written, re-reading the blurb, the author mentions a tech editor, so you’re really sure it’s well written, but you want to use your own yarn. How do you know it’s enough?

Look on the belly band of your yarn, or look the yarn up on Ravelry. Somewhere on the tag or belly band, it should tell you how many grams or ounces it weighs, AND how many yards or meters long it is. Now you have a conversion factor, the ratio of standard length to weight, invert it, it’s weight to length. What do you do with this ratio? Remember those problems on unit conversion AKA dimensional analysis – take what you know, and convert it to what you don’t know.

Let’s say you know the yardage of your yarn, but not the weight.

Length of Your yarn X Belly Band Weight / Belly Band length = Weight of YOUR yarn.

Now let’s say you know the weight of your yarn, but not the length.

Weight of Your yarn X Belly Band Length/ Belly Band weight = Length of YOUR yarn.

But what if your yarn doesn’t have all that info for some reason? If you have access to an accurate scale, you can measure off 10 yards, weigh them, and use them for your conversion ratio. Where to find an accurate scale? A Ravelry group suggested the scale in the produce section of your grocery or farmer’s market, or a mail scale in the office. I send my swatches and yarn balls to the lab with my husband, he can measure to the 0.001 grams.

That should put you in the ballpark for knowing if you have enough yarn. Be sure to check your measurements (either your body if you know how you like your clothes to fit, or the measurements of a similar garment to what you want to make that fits you well) against the schematic in your pattern. If you are able to shorten sleeves, or body length, you may save some on yarn, but remember, if you are tall, you will need more than the pattern calls for.

And if your pattern doesn’t have a schematic?

That’s another post.

A harder one to write so I might not get to it…

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