Digitizing Threadings

To “digitize” is to convert something which starts out as continuous data into packets of discrete information, like converting a photograph into a digital file. Threadings are already in digital form – one square equals one shaft or block. So “digitizing” a threading refers to reducing the number of shafts by combining some of them – like reducing the resolution of a digital image by combining pixels.

Weaving software has the option to digitize, but it’s easy to do manually in order to control the process. A common method is to reduce the number of shafts in half by combining shafts in pairs. But other reductions and combinations can be chosen. The number of treadles is equal to the number of reduced shafts. And a straight treadling parallel to the tie-up is used so that the drawdown, which becomes the new, reduced threading, travels in the same direction as the old threading for a direct copy/paste.

Digitizing can be used in other ways. In particular, it can be used to extract the design line from a pre-existing draft.

To illustrate this, a 4-Colour Double Weave (4CDW) draft is created from the original (not digitized) design line.

I like it, but the scale of the design is too small. I want to double the size of the design. The easiest way is to double the design line. But, let’s pretend that I don’t have the design line – maybe I forgot to save it, or maybe the 4CDW draft came from another weaver. Is there something else I can do with this draft to double the size of the design? Yes.

This draft is already effectively doubled. It uses an extended parallel repeat in the threading, and a parallel repeat automatically doubles it. So if I can get this threading back into the form of a design line, without changing its length, I can use it to create a new 4CDW design which is twice the size.

To do this, the design is digitized to four shafts. If I want to use weaving software to digitize it, I need to shuffle the shafts into a straight twill arrangement. But if I digitize manually, I can skip that step and place the tie-up in a parallel digitizing arrangement to get the same result.

The reduced threading has a section which is “extended”. Instead of the design line continuing upward in the same direction, it wraps around from shaft 4 to shaft 1. It doesn’t need to do that, because we still have eight shafts to work with. So that section is moved up to shafts 5 to 8 instead. And the design line is now starting to look very similar to the original design line.

Duplicate the steps used to create the original 4CDW draft, and here is the end result. The design was successfully scaled up while maintaining its original appearance.