Weaving a twill structure gamp

Last week I told you about the color gamp I wove a while back, that allowed me to see how 20 different colors of the same yarn would look when each of them interlaced with every other one.  I have referred to that gamp many times to help me choose colors that go together in surprising and exciting ways.

That was such an informative project that this past couple of weeks I've been designing and weaving a twill structure gamp.  It follows the same principle as the color gamp, only this one explores many varieties of twill structure, specifically the way various twill threadings interact with various treadlings.  Color changes are limited to those that allow the weaver to see easily where the different threadings and treadlings start and stop.  So the warp is all one color (here, white 10/2 Tencel because I had plenty of it), with narrow green 8/2 Tencel stripes between each different threading structure in the warp.  The weft is taupe 8/2 Tencel, again with green stripes dividing each section of different treadling.

loom warped with twill gamp in white with green dividing stripes

So the variables being studied here are the interactions of threading and treadling that create the almost countless various twill structures.  The loom is threaded with 10 different twill structures, each about 1-1/2" wide, from a simple "straight draw" on the right edge, through various standard twills, broken twills, hopsack, and so on,  to a wide undulating twill at the left edge.  The really fun part is then exploring some of the many possible treadling patterns.  To start, I used the threading patterns as treadling patterns (weavers call this "tromp as writ"--don't you love that Anglo-Saxon lingo?), and then I explored some of  the variations on those treadling patterns.  I followed closely the instructions in Janet Phillips' book Designing Woven Fabrics as I planned and wove my twill gamp.

Because my counterbalance loom does not easily make a shed for 1/3 or 3/1 twills, nearly all the patterns I tested were variations on 2/2 twills.  Still, I was able to do 38 different treadlings.  I discovered that in order to try the maximum number of treadlings, I needed to use a skeleton or universal tie-up, with each treadle tied to only one shaft.  Thus, I'd need to use both feet to make each shed.  I was a little unsure about this but I soon got used to it.

Twill structure gamp in progress

One of my goals this year is to become better at designing pieces that combine various twill structures together for a more complex woven surface.  Already this gamp has given me some ideas for the next set of towels I'm planning.  Below you can see a closeup of one end, with hangtags labelling each threading for easy reference.  I've placed masking tape labels along one selvedge, allowing me to easily count the rows of treadling so I can check my weaving records and identify which treadling I did in each row.  In the photo you can see how I've folded and pinned the gamp so the extended twill threading is at the top.  I have decided to make the towels using this threading and this allows me to isolate that column and study each treadling so I can choose those I want to explore in the towels. 

Twill gamp folded and labelled for study

 You can also see one heavy blue thread near the bottom edge, just above the green hem.  That is a "face mark" that tells me this side is the right side of the fabric. 

Completed gamp

I know I will be referring back to this gamp for years to come and using it as inspiration for planning countless pieces.  There are a total of 380 patterns here!  Not all of them will work, but many will.