In painting that 18 inch weft I'd intended to use on this 18 inch warp, I completely forgot about take up! To the uninitiated, what that means is that it takes more than 18 inches of weft to lay in a pick 18 inches wide. That's because of the take up that occurs as the weft yarn goes over some threads and under others. It actually requires about 10 percent more than the weaving width, which would be close to 20 inches per each pick of weft. In other words, that 18 inch weft I painted needs a warp of 16.3 inches to work! Rude awakening here. I usually have more than enough weft yarn so I don't really consider take up in my calculations. But this time I should have.
So, the NEXT piece I warp will be 16.3 inches wide to accommodate that painted weft. Yes, I am determined to get it woven up, and the next piece will do it!