Posted by Peg in South Carolina
As I continued staring at the tieup in Smith’s draft, I slowly began to realize what I had been doing wrong: I had been trying to see a twill tieup pattern that went through all 8 treadles. What I had forgotten was that I was dealing with each set of four shafts individually, not as a whole unit.
Here is my incorrect tieup. It was based on trying to get diagonal lines to run through all eight treadles. Well, it does, but only on the first two treadles.
QUADRANTS AND CORRECT TIEUP
Here is the correct tieup. The diagonal is there on the first four treadles of the first four shafts. And it is MIRRORED in the first four treadles on the second four shafts. But what about treadles 5 through 8? Here things are just reversed. The lower left quadrant becomes the upper right quadrant and the upper left quadrant becomes the lower right quadrant. The result is that there is a twill diagonal which runs through each quadrant; it just doesn’t run through the whole tieup.
So to read tieups like these I have to remember to think in terms of quadrants, not in terms of the whole.
I SHOULD HAVE KNOWN
The major irony is that I had already written about precisely this phenomenon in an earlier post! Go here if you would like to read it.