As you’re probably aware, flipping a structural tie-up over – that is, switching black and white in every square of the tie-up, so that every shaft that was tied to a treadle now isn’t, and every shaft that wasn’t tied to a treadle now is – also flips the fabric over.

Flipping a tie-up over like that is known as changing its face. When you do it, you also change the face of the cloth: what used to be on one face (the top, for instance) is now on the other face (the bottom), and vice versa.

Here’s a Bronson Lace structural draft, followed by the same draft with the tie-up flipped over:

Notice that corners are plain weave and the cross is lace in both versions. The lace hasn’t moved but it has changed color. In the first draft, we see the blue weft floats on the face of the cloth. In the second draft, we see the white warp floats on the face.

Here are the tie-ups for each of the above drafts at a readable scale:

You can see that they’re exactly the opposite of one another: what’s black in one is white in the other and vice versa.

This is an example of changing the face of the tie-up and of changing the face of the cloth. Doing the first causes the second to happen automatically. 

Changing the face of the cloth sometimes happens by accident – if your loom has a rising shed but the draft you’re following is written for sinking shed, for instance.

Changing the face of the profile

If you’ve taken Profile Drafting – The Basics, you know that the structural tie-up of unit weaves can be divided into two sections: the pattern section , which corresponds to the profile tie-up, and the ground section, which always follows the same rules.

Now compare these two drafts: 

The plain weave and lace in the first draft switch places in the second. The color of the lace has not changed, however: we see the blue weft floats on the face of the cloth in both drawdowns. 

Since the lace has moved but hasn’t changed color, we know we haven’t changed the face of the cloth this time. Instead, we’ve done something related but different.

Take a look at the tie-up from the first draft with the tie-up from the second:

Just as in Profile Drafting – The Basics, the section of the tie-up bounded in orange is the part of the tie-up where pattern shafts cross pattern treadles. The rest of the tie-up is where the ground shafts and treadles are.

Notice that the ground shafts and treadles are exactly the same in both tie-ups, so clearly we haven’t changed the face of the entire tie-up like we did earlier.

If you compare the pattern sections of the two tie-ups, you see what we’ve done instead is to change the face of only the pattern section.

And, as you can see from looking back at the drawdowns, changing the face of just the pattern section of the Bronson Lace draft caused the lace and plain weave to swap places.

Changing just the pattern section of a unit weave’s structural tie-up is called changing the face of the profile, rather than the tie-up or the cloth. (Remember: changing the face of the tie-up means changing the entire tie-up, and results in changing the face of the cloth.)

That makes sense given that the pattern section of the tie-up is based directly on the profile tie-up, so what you’re doing amounts to changing the face of the whole profile tie-up before it’s turned into a structural tie-up.

To learn all about unit weaves, profile tie-ups, and structural drafts, be sure to take Profile Drafting – The Basics!

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From the course Profile Drafting: The basics: