Wednesday, July 22, 2015

Yes, I still remember how to quilt...

Although I haven't been in the blogosphere much lately, that doesn't mean I haven't been getting my hands dirty.  In addition to indigo dyeing, I've also been working on a bed quilt, which I started basting last night:

I'm tired of our ratty old Ikea duvet and decided that we ought to have a real quilt on our bed.  A couple months ago or so, I bought on sale a kit of Birchtree Lane fabrics, with their fun bird, leaf, and feather designs, which I supplemented with various tone-on-tone fabrics in whites and light browns.  I didn't make the actual quilt design of the kit, but did simple diamond-in-a-square blocks.  My sewing machine is headed to the shop for a thorough cleaning, and when it comes back, I will be ready to quilt!

Linking up to WIP Wednesday on Freshly Pieced and The Needle and Thread Network.  Happy sewing!

Monday, July 20, 2015

From the indigo vat: Solids

I'm always like to test the vat out by dyeing a range of solids:

From left to right, the six shades involved, respectively, 3, 4, 5, 8, 14, and 20(!) cycles of dipping and oxidizing. The 4- and 5-dip pieces were done separately from the rest of the lot, after I saw some final results and wanted to fill in a couple of gaps in the gradation.

The solids taught me a lot about the vat.  After the first half dozen dips or so, the fabrics didn't seem as if they were getting much darker, and at times I wondered if they were actually losing color.  Very frustrating!  But I kept going anyway, to see what would happen, especially after the vat reached a dark amber that made me think it just had to be working properly and adding more blue.  After I washed the final two pieces on the right, the true color underneath was significantly darker.  Somehow, the zinc-lime vat seems to leave a lot of unreduced indigo on the surface of the fabric, which later washes out and reveals some happy surprises.

At the same time, I was able to get to dark shades more quickly with last year's thiox vat.  The 20-dip piece on the far right isn't really any darker than a good dark blue that I got after about eight dips last summer.  In the workshop that I took last fall, Gasali Adeyemo says that he gets a dark blue in just 3-8 dips, which suggests that if I want really dark blues, I can be much braver about using a heck of a lot more indigo than most of the standard vat recipes suggest.  I tried to look up the maximum solubility of indigo in an alkaline environment, but no luck thus far in getting that particular chemical statistic.

I also can't honestly say that the blues from the zinc-lime vat are significantly different from the ones from last year's thiox vat.  Maybe the difference in tone from the Japanese fabrics in my collection comes from the indigo?  Or something else in the vat chemistry?  I wish I had some Japanese indigo that I could try, for purposes of comparison.  If anyone wants to bring me some natural indigo from Japan, derived from polygonum tinctorium, please feel free to do so!  Or if you want to grow it yourself and ferment it for me, I will happily try it out!

Saturday, July 18, 2015

Indigo 2015: The vat

I've been lazy about blogging, but I've been busy with this summer's indigo dyeing.  This year I'm trying a zinc-lime vat, which takes time to set up, but is supposed to produce deeper, richer blues than the thiox vat.  In mid-June, I prepared my first stock solution:

The stock looked really good after five hours of reduction--the dark amber color was just what it's supposed to be, and there was a good, thick layer of  indigo "flower" with a nice bronze sheen on top.

This vat uses zinc as a reducing agent in combination with calcium hydroxide (lime).  Although the zinc-lime vat has a reputation for being a bit tricky to manage, it has a number of advantages in addition to the colors that it produces.  It reduces indigo efficiently, works at room temperature down to about 60 Fahrenheit, and can be revived even after months of non-use.  Unfortunately, as I noted in an addendum to a previous post, the zinc is rated as a hazard for aquatic life, so the vat has to be disposed of properly as hazardous waste and can't be poured down the drain.  In the longer term, if I want a room temperature vat, I'll have to switch to a ferrous sulfate vat.  It doesn't have the efficiency and longevity of the zinc-lime vat, but is better for the environment (at least as far as anyone knows at the moment).

I had difficulty with the vat for the first several days.  Various dyeing guides talk about looking for a "French mustard" color or a color ranging from yellow to dark amber, depending upon the amount of indigo in the vat.  I thought I had a vat on the yellow-ish side when I first started dipping, but after several rounds, I didn't seem to be building additional color, and my first fabrics weren't very well dyed.  In retrospect, I think the vat was too green and the indigo wasn't reduced enough.  The initial vat also didn't stay chemically balanced as long as I thought it would, and when I went away for a weekend after the first few days of dipping, the vat died completely.  I fiddled with sharpening the vat by adding various combinations of additional zinc, lime, and indigo, and eventually, after about ten days after the original stock solution, I got the following result:

At this point, the vat seemed very bubbly and lively, with lots of dark blue "flower," flecked with bronzy blue bits.  The vat liquid itself reached a perfect dark amber, and I felt certain it was just right.  I immediately started dyeing some elaborate nui shibori pieces that I had laboriously stitched and tied a while back, but didn't dare dye until I felt confident about the vat.

I'll discuss the results of my initial round of dyeing in the next few posts.  Indigo Summer 2015 is well underway!