GroundForge

Bobbin Lace Diagrams : threads from pairs

View project on GitHub

Droste effect

Pair diagrams of several traditional grounds are very similar to thread diagrams of more basic grounds. The differences in the basic grounds are the stitches.

The principle of using a thread diagram as pair diagram can be used over and over again, in theory. In practice the holes will grow very large. The diagram generator supports up to lever 3. At level 4 browser would choke even with a very small number of repeats.

At each level you can mix stitches resulting in a myriad of patterns. The following table shows just a few options in the level-2 column. The last column mentions patterns of the Whiting index, some times they are mirrored or have other small variations.

level 1 interactive
diagrams
level 2 Whiting index
single stitch click 2nd too!    
ct-ctct A5, A6, B5, C6, A7-H7,G11
ctct-ct/ctct A2, B2, B6, C6
crclct-ct/ctct C6
clcrclc-ctc  
ctctc-ctc F2
stitch mix      
2 x ctc+t* D16
2 x ct/ctct surprise!  

*: the second level pair diagram looks a bit weird because “stitches” don’t cross.

Seed your own experiments

To mix stitches at the first level, you can use patterns of the Tesselace index or get your feet wet with designing patterns from scratch. Enter alternating -’s and 5’s or an even number of alternating rows of 8’s and 1’s, as shown below. Just try which ones of the purple tiles produce a valid pattern.

Choose Stitches

At the first level you can choose your stitches in the prototype diagram, click the to show the result.

Some stitches to copy paste:

crclct
clcrct
clcrclc
crclcrc
ctctc
 
ctclctc
ctcrctc
ctclcrctc
ctcrclctc
ctcttctc
 
tctctllctctr
tctctrrctctl

Only less trivial stitches are listed, drop or add twists at will. Each second string is the mirrored version of the stitch. Note that the last two are perceived as two stitches by lace makers, they show up as one stitch in the pair diagram, the pin is left out.

Stitches at the 2nd/3rd level

The second and third level have a less convenient method to select stitches. The team of GroundForge can use a seasoned front end engineer for a more convenient user interface.

You can choose to use one stitch everywhere. Or two different stitches: one for each cross in the preceding thread diagram, the other for each twist. To make exceptions to these rules you need to hover over a stitch in the pair diagram to discover its id for stitch assignments.

An example mixing all the options mentioned above:

The overall default in this example is a ctct. A more selective default is ctc for stitches that were twists in the preceding thread diagram. Two specific stitches are set to ct.

Note
Spaces may have unexpected results, recommended delimiters between assignments: new lines or ,.