Saturday, February 19, 2011

Second and third dyeing experiments - third time's the charm!

Here is attempt #2 at dyeing wool roving in this particular colorway.  I did kind of a no-no and changed two variables at once, But I'm pretty sure I still would've had to do #3 anyway, so no real time lost here. 

After having so much dye left over last time, I decided to try not doubling the dye-to-fiber ratio for dye painting, as recommended in Color in Spinning, and just go with the immersion dyeing ratios.  I also changed my method of applying heat for setting the dye.  In the first experiment I used the steamer technique, where you wrap your dyed roving up in a long piece of plastic wrap, then roll that "snake" up into a "snail" and place it in a steamer basket in a pot on the stove with water, and steam it for an hour at about 180F.  The tricky part here is trying to maintain the temperature.  If it goes much above 190F you can damage your fiber, and although the dye is supposed to start setting at 150F, it seems to take forever, and it's difficult to gauge the timing, so I try not to let it get below 175F. 

 I'd seen references to people setting dye in the oven instead, so I decided to try that in hopes that it would be easier to maintain a consistent temperature.  Several people had said they had good luck with an oven temp of 250F for about an hour, so that's what I tried.  What I should have done was stick my thermometer in the fiber to make sure it was getting hot enough.  I was lazy, and decided to "follow the recipe."  I still had my roving wrapped in plastic wrap, then I placed it in a plastic bag before putting it in a baking dish because I didn't have a pan I wanted to dedicate to dyeing.  It was impossible to tell whether the dye had exhausted without poking holes in the plastic, which of course would result in the dye leaking out.  When I rinsed the roving I found that indeed, much of the dye had not set, and while I was getting the charcoal grey that I was looking for, the blue and the blue-green were much more muted than I'd intended.

Here's the resultant yarn.  Again, very pretty, but still not what I had visualized.  I knew why I hadn't achieved the saturation in the colors that I wanted (the dye had not exhausted), but I was also disappointed that there still didn't seem to be enough distinction between the blue and the blue-green.  They were still blending too much in the roving.

In doing a little deeper research, I found that people who oven-dyed for their business tended to use oven temps closer to 300-350F.  Also, a lot of them were dispensing with plastic wrap entirely and laying their roving out in a zig-zag in a roasting pan, applying the dye, then covering the pan with tin-foil before putting it in the oven. For my third attempt, I went and got a cheap aluminum roasting pan.  When I applied my dyes, this time I made sure that the blue and the blue-green were never adjacent to each other, always having the grey between them.  I used my thermometer (the one I have has a cable that plugs into a temp readout, so I can shut it into the oven and monitor the temp from outside), and set the oven temp at 300F.  I still had to do a lot of tweaking with the temperature (turning the oven up and down, opening the oven door, etc), and left it in for a total of about an hour and a half.

Tah-dah!  This is what I was aiming for!  All the dyes exhausted, the grey has not turned black, and the blue and blue-green have not blended together - you can see that there are two distinct colors in this roving!  The roasting pan technique also took up a lot less space on my tiny counter, which, with my clumsy self, is a definite advantage!  I can see being able to fit probably two rovings per roasting pan of this size, and I should be able to fit four pans in the oven at once.  Eight at a time is not bad!

Here is the yarn from this last roving.  Still fairly subtle, still some blending in the yarn, but that's OK because that's where I want the blending to occur.  But you can see three distinct colors, not just blue and grey like the second yarn, or blue and black like the first.  It's all about control, and being able to get the results you were expecting.  I'm sure I will still get lots of unexpected results, but at least now I seem to have the biggest variables (more-or-less) under control.  Now I can start thinking up some different colorways!  I'm really glad this only took three tries - I was going to get really tired of this color combo if I didn't figure things out!

Thursday, February 3, 2011

Experiments with painted roving

 So I've started experimenting with painted roving.  Yes, technically it's not roving, it's combed top, but since "painted roving" has become the generic term for this product regardless of whether it's actual roving or top, that's how I'll refer to it.   It's very pretty, but not quite what I was going for.

In dyeing, the intensity/darkness of your final product is determined by a ratio of dye to fiber, by weight.  If you want a lighter color you use less dye, if you want a darker color you use more.  Sounds logical and reasonable, right?  This relative intensity of color is referred to as Depth Of Shade, and is generally abbreviated as DOS.  If you want consistency and repeatable color (e.g. professionals and perfectionists), you will not just toss everything in a pot and see what comes out - at least not without keeping very careful notes! 

If you want consistency and repeatable color you will use a formula to tell you what ratio of dye to fiber will give you a certain DOS.  The current dyer's standard (as far as I can tell) is to use a scale that generally starts with DOS .25 (very pale) and ends at DOS 4 (as dark as it's possible to get for that color).  In immersion dyeing, where you are dyeing everything one solid color, if you want DOS 1 you use a 1:1 ratio of dye to fiber.  A DOS .25 would be .25:1 dye to fiber, etc.  You then add enough water for the fiber to move freely and "cook" everything at the appropriate temperature until all the dye in the water has been absorbed by the fiber.

With dye painting it's a little different.  You have individual cups of dye that you apply directly to the fiber.  You place the color exactly where you want it, and have some degree of control over how much the colors blend where they meet.  There is also an optimum amount of liquid that can be applied to roving for dyeing. If you use too much, everything blends together a lot more and you have less control.  Too little, and you end up with undyed spots where you don't want them.

According to Deb Menz, when you are doing painted roving, you should use double the amount of dye to get the desired DOS.  I'm not sure why or how this is necessary, or how much of it is just "fudge factor."  I wanted the test roving at the top of the page to be a medium grey, a medium navy, and a dark forest green.  Even though I know I did all the math correctly, I ended up with way too much liquid!  While she provides good Three Bears examples (too much, too little, just right), she doesn't say "You may not need all the dye you have mixed to achieve this."  By the time I had applied the blue, the green, and half of what was supposed to be dark grey, my roving was sopping.  I stopped adding dye because I knew this was way too much, and decided to see what I would get with what I had.

What I got is at the top of the page.  The grey is still black (not dilute enough), the blue is darker than I was expecting, and they both have pretty much swallowed up the green.  Obviously I had more dye than I really needed, and I can't afford to rinse color down the drain for the sake of "fudge factor."  I will try this again with some modifications, and we'll see what happens!

That said - it still made very pretty yarn!

Tuesday, February 1, 2011

"Dyeing" to figure this out

dye tests in water bath
Several years ago when Color in Spinning by Deb Menz came out, I dipped a toe in dyeing.  It didn't stay dipped very long - I was still working full-time, and this was also after Scarlett was born, so time and sleep were at a premium.  This is one of the projects I let go.

Color in Spinning is pretty much the guide to using professional dyes (as opposed to Kool-Aid and Rit) on natural fibers intended for handspinning.  It's a fantastic resource, and has great step-by-step detail on every aspect of dyeing both protein and cellulose fibers.  There are instructions for dyeing big fluffy "clouds" an even, solid color, and instructions for painting dye onto tops or rovings (which are essentially long thick "ropes" of fiber) for producing variegated yarn.

These "painted rovings" are very popular among spinners because no matter how much you love spinning, miles and miles of the same color can be very boring!  The color changes in a painted roving add some variety, plus you never know quite what the finished yarn is going to be like, which also adds some excitement!

I still had the dyes from my first attempt, so I decided that now would be a good time to try this again!  The first step in this process is to make color samples.  Color in Spinning starts with a set of eleven colors of dye, and then gives formulas for another 56 colors that can be made with those original eleven.  There is no color card, so if you want to know what those colors look like, you need to mix them up and dye them.

bits of dyed wool drying on top of my bookshelf, out of Scarlett's reach
I decided that 10 grams of wool was a good sample size (nice and easy to measure), but at that relatively small weight, I would need to measure certain chemicals used in the process in fractions of grams.  I knew that this was my downfall the first time around.  At the time I only had a triple-beam balance scale.  While it was incredibly accurate, it was also extremely tedious to use, and took a lot more time than I really had.  Now I have a nifty little digital scale that has made that step so much faster and easier!

 I have been working on my sample notebook.  I'm using binder pages meant to hold business cards, and I put a little piece of fluff or yarn in each pocket, backed with a piece of cardstock that has the color name and formula on the other side. Each side is also labeled with the number of the dye formula as given in the book. It's really nice to be able to just flip pages and see what colors I might want to use.

I'm more than halfway through the 56 colors.  Unfortunately I've run out of Sun Yellow.  As you can see, the page with my yellows and oranges on it is looking a little sparse.  My page of greens, sadly, is in a similar state.  I am waiting for the Goddess of Fortune to smile on me (IOW - waiting for someone to buy something from me!) so that I can get more dye.  In the meantime I'm going to explore painting roving with the colors I've got.  I bought 5 lbs of Romney top with my Christmas money - should be enough for 20 or 30 different color experiments!
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