I'm still digging through my stash for weaving supplies.
Sometimes I'm not sure I have quite enough yarn, or I want to make sure the scarf won't end up way too short or with a lot of leftover yarn. So, I have to do a little math.
I dug out two balls of sock yarn to use. One is Regia World Circus Colors that my mom gave me some time ago. It's a full ball - 420 m or 459 yards. The other is a leftover 36 grams of Simply Socks Yarn Company Solids in Natural. That should be around 126 yards.
For starters, I have 3.6 times more Regia than I have solid yarn. I can make my weaving easier and faster if I only use one color for the weft. So, that means I should use the Regia for the weft.
My easiest warp to wind can be either 70 or 86 inches long. I want to use the 12.5 dpi heddle on the Sample It loom. If I use every slot and hole, that means there will be 100 ends on the warp. If the warp is 86 inches long, it will take about 100 x 86 = 8600 inches, or 239 yards, to warp.
At 86 inches long, all of the Natural yarn could be used to make about 52 of those ends. I want the pattern to be balanced on either side, so I'm going to use 52 ends of Natural and 48 ends of Regia. (I use the direct warp method, so it's easier if these are even numbers.) That uses up 115 yards of Regia, leaving 344 for the weft.
344 yards for weft should be more than enough. Most people figure the warp will be either 50% or 60% of the project. Even using the 50% calculation, I should have enough yarn for weft, with at least 105 yards left over.
But, just to check. Each inch of weaving will use (at most, if I don't pack it in too tightly) 8 x 12.5 = 100 inches of weft yarn. The usable warp will probably be 86 - 18 = 68 inches long. So, I should use 100 x 68 = 6800 inches, or about 189 yards, of weft yarn.
I'll let you know how it goes! I hope it isn't completely ugly.