getting blue!

On the tray is all the woad cut at Helen's on September 4th, about 450g. Several plants had grown better than mine, that is, they had bulked out though were still not as fully grown as expected. Others were middling, like mine, with a few well and truly eaten! But only three caterpillars emerged during the wash!

The four pots from my front garden yielded a further 50g, so in all I had about half a kilo. About half I'd been hoping for – but quite acceptable considering August's lousy weather. The left hand pile is good wholesome leaves, the top those that were fairly battered, bruised, part-eaten and part-rotting (bad bits later cut out). Can't quite remember what the right hand pile is – possibly small and slightly battered leaves.

While washing my leaves I felt they were more blue-green than Helen's, so compared them. One-all I think, if mine are bluer but hers grew better. I'll come back to the growing stuff later.

Half a kilo of chopped leaves - including stalks. I reckon stalks must contain some indigo too, and having so few leaves/weight I couldn't afford to be discriminatory.

Whisking time is telling time... when the alchemy works or doesn't. In my case I was leaping with joy to see so much blue pigment (indigotin) in the foam, and appearing so quickly! I was expecting the foam to turn 'back to green' within 10-20 minutes of whisking, but all I was getting was more and more foam, and blue. The bucket was less than two-thirds full of liquid - top third all foam! I tried scooping it off and re-whisking, I tried mixing the foam back into the liquid, I tried giving it a break for some minutes. But still foam came up good and blue. In the back of my mind was a vague memory from one or more of the various indigo workshops I've been on, where a similar stage in vat-making required stirring to introduce oxygen - and being told soon after that it had worked and I could stop stirring. And so an hour later I convinced myself that I surely had whisked enough, there certainly was blue there (and everywhere!), and I could move on to the next stage - bottling. The memory of stirring at an indigo workshop remains vague and, in the light of day (I stopped whisking around 1 am!), not making sense. Either I was confusing the process with another, or we were processing woad (or other) leaves to make indigotin without me realising. Anyway, whatever it was, it helped me at that time - I had started to think about what I was doing, the process that was happening, instead of just following instructions!

This yellowy-green is the colour of the liquid going into the jars.

Total of seventeen jars. At this stage I deviated from the instructions, which called for periods of settling and siphoning off of the top liquid, followed by a consolidation of all bottom liquids into one container, with the top liquid being diluted with water and siphoned. Each time I pulled off the top liquid it was greenish, making me suspect there was 'blue' in there too. I saved all siphoned liquid, letting that too settle before re-siphoning. In all, I had three separate siphoning stages. After a few days of settling, some jars were showing a central body of amber liquid, surrounded by greener tinted liquid and a strong blue bottom layer (see previous post). It demonstrated to me that my earlier instinct was right, that the top greenish liquid had contained some blue pigment, and a longer settling time was all that was needed.

All liquid from the last siphoning went into the bucket, and a few days later when its top liquid was siphoned off it revealed yet another bottom layer of blue!

Although it obviously wasn't traditional to use filter papers, I did think it was perhaps the modern take on a traditional filtering technique - and had read it would yield more indigotin. I also thought it might yield more if I didn't repeatedly 'water down and re-siphon' the liquid, as early on the top liquid had proved to also contain blue pigment. So I started filtering undiluted liquid - some greener, some bluer. My instinct paid off again - see how golden it came out (in a beer glass from a Bodmin Beer Festival, and looks good enough to drink!).

Filtering started at a rate of about two drops a second. By the end it was one drop a minute, which is why by then four filters were on the go! But slowness wasn't the imminent problem. Soon after starting the filtering, I was wondering how to get the pigment off the paper at the end. The more I thought about it the more I wished I hadn't started down this route. Perhaps an upside is that it made me concentrate on related chemical processes to look for a solution. There may be one but far too long-winded to take seriously, though I might check it out sometime.

Two dried filter papers with skims of pigment over some, and a crust in parts. The crust cracked up like dried mud. If it had been thicker it might have picked off cleanly, but for me it took some paper fibres with it. The very thin layers I scored lightly with a scalpel before brushing the fine powder away. But some paper fibres went too. Pigment and fibres weighed in at two grams.

Four filter papers, as much pigment as possible removed. Took about a day. Now, had I followed instructions to consolidate the bottom liquid more and dilute it down with water, this end result might have been different. Probably I'd have had just one filter paper, so the pigment on it would have been thicker and more easily removable. Possibly it would have not seeped so far into the paper had the pigment been suspended in water instead of the remnant alkaline solution. Possibly... probably...

One thing is for sure though: a lot of pigment remains on the paper. This macro-shot shows how much is wasted. Criminal considering time and effort - mine, Helen's and nature's. I won't be using filter paper again.

With thanks to Teresinha Roberts, Helen (in North Wales) Melvin, and Ian Howard for various processing instructions, guidance and encouragement; to Ian Howard, Isabella Whitworth, Vivien Prideaux, and Abi Evans for past indigo workshops which helped develop my understanding of the indigo-making process; and to Ian who supplied the seed I grew. And not forgetting members of the Natural Dyers list. Special thanks go to my good friend Helen (in North Cornwall) for patiently growing, watering and de-slugging my woad plants over the last few months.

indigo pigment settling

Not particularly beautiful jars but against the light the process can be seen of indigo pigment settling out from woad-steeped liquid. The centre top of the liquid clears to amber, while the glass edges seemingly attract pigment or somehow otherwise slow it sinking (greener colour). Temperature difference? Anyway, there's a nice pile of blue building up at the bottom - I was so excited when I saw how much!

I haven't yet finished the woad processing - I will post again when it's all finished.

straight and curly, and thin green lines

These photos were taken on August 2 (4 weeks ago) as I'd noticed a variation in the woad plants. Some plants had straight edged leaves, others were wavy. Helen (growing most of my woad) has also noticed this. I wonder if it's a genetic mutation, or a natural variation...

The plant that was bitten to the core by slugs is growing back well (leaves still small) (see bottom photo in last post), the other three have been chomped away at relentessly throughout August. There is less of them now than there was at the beginning of the month. In recent days I've been thinking caterpillars are more the cause than slugs. A Cabbage White butterfly was around and on the plants around the beginning of August, as were little yellow dots of eggs on the underside of leaves. I thought I'd got all off but no, every so often a tiny green line would show itself... a few days ago one thin green line was nearly up to full blown caterpillar size! (When very small I squeamishly have squashed them, but larger ones I take up the road to take their chances in the verge vegetation).

The August weather has been atrociously wet and cool, with a few February-like gales. Only occasionally did the sun shine but it was hardly ever summer-hot. I'm sure this won't have helped the crop either - I feel it's the cause for the (former) large outer leaves to have dried up, died in parts, or yellowed. The inner newly sprouting leaves are all good and healthy. Just right for nibbling. Undoubtedly. Hmmph.

None of the woad has had (nitrogen oriented) fertiliser in its soil, though Helen's beds had before she grew the earlier potato crops and mine had a good portion of home-compost. Perhaps fertiliser would have helped the plants gain strength. I've found an organic chicken rearer who I hope to get well-rotted chicken manure from next year. And perhaps next time butterfly netting would keep off the cabbage whites... Though most of the growth problem could be caused by their late start in life. They must be sown at the right time next year!

I am gearing up for harvesting and processing the leaves in several weeks time - acquiring equipment and organising workspace. And am working on batik drawings so I have cloth ready to dye soon after.

shredded woad

Helen, who is growing most of my woad for me, emailed a bit despairedly on Monday. Slugs being the main cause, and her concern that I wouldn't have any leaves left come harvest time. I popped over that afternoon, the following photos are from that visit. These first four show various stages of shreddedness... but most plants were doing just fine.

And so... slug control: Helen has access to sawdust, I have access to coffee grounds so we are trying both. The coffee was applied just before this photo around up-till-then unprotected plants. Most successful seems to be a copper ring (top and bottom right), but only a few plants have these, and only one has broken eggshells (white). Research suggests that coffee grounds release nitrogen into the soil, an element apparently loved by woad - or rather its uptake increases eventual pigment quantity. I've also read that coffee grounds have an anaerobic effect if applied too thickly, and that it's either acidic (which can't be too good when your soil is already acidic) or breaks down to neutrality (which shouldn't matter). There is more to consider though than woadish preference - nitrogen broken down by bacteria forms nitrous oxide (N2O), a far more potent greenhouse gas than carbon dioxide. Not being a chemist I'm really not sure of the pros and cons of using it as slug repellent and soil fertiliser, or even of growing nitrogen-loving woad itself... but I will find out! At least the coffee grounds (like the sawdust) are already waste products that would eventually decompose anyway.

Helen has created three plots for the woad. The first is in a spare part of her raised walled veggie garden - I think she said courgettes were growing there until the slugs got 'em. The next is a raised bed that last grew potatoes; and the third is part of the bank that had been covered by carpet to kill couch grass (roots were dug out before planting). All sites get loads of lovely sun... and rain, it being the Cornish summer holidays now.

And finally, four of my five potted plants. Three are teenagers now and allowed out all night but the fourth (back left, in ceramic pot) is still a kid and comes in around midnight. A few days ago I came home feeling so unwell I didn't have the energy to bring it in... and yes, the slugs took advantage. But it's still growing. The fifth plant is elsewhere with the tomatoes and aubergines, a different mini-climate, so I can see how location changes growing patterns. All of mine have had coffee grounds protection from their first venture outdoors.

cost of boiling out wax

...in an interim stage of wax removal in the Feeding the Ducks batik:

Ten litres of cold water in the Burco took 23 minutes to reach boiling stage, and the (metre square) batik was submerged for a further 22 minutes with the power intermittently on. The total 45 minutes 'boiling out wax' activity used 1.4 kwh of electricity. Translating to 0.6 kg CO2.

Starting with warm or even room temperature water would have saved a little energy, but more would have been saved if the batik hadn't needed to boil for so long. Sometimes a few minutes dip is enough to melt and remove wax but other times the wax leaves a yellowish residue that takes longer to shift. It's often only visible when the batik is wet but can affect subsequent dyeings, such as had had happened with this last dyeing.

Experience suggests this happens when wax has been 'well cooked', turning brown, and where used has lost some ability to repel water/dye. In turn, being well cooked could mean the wax is being heated too high, ie where it touches the hottest part of the bowl it's getting hotter than ideal. But if I have the pot at lower temperature then the wax isn't hot enough for fast canting work.

I removed the 'old' wax, cleaned the pot and replenished it with new wax to the same recipe (100 g batik mix, 20 g white beeswax). This time I used half quantity, ie half filling the pot and heating at setting '5'. Always before I've filled the pot to ensure a consistently heated supply of wax, but my thinking now is that if there is less wax to start with then the pot needn't be set so high to get the ideal wax temperature. The wax is both less likely to be 'cooked' on the hot part and - importantly - used up by the time replenishment is needed!

I am truly shocked to find that of the 240 g of wax heated last time round, 145 g was removed too 'well-cooked', meaning only 95 g was used for the batik. I have been very very wasteful of resources and am determined to get this amended.

Another thought I had for saving energy with boiling out wax is to insulate the Burco boiler. Followed by hesitation from the likelihood of getting the insulation both very wet and coated by molten wax spluttering over the Burco top. And from remembering the hint from Paul Mobbs that beyond a certain depth (0.2m) loft insulation becomes carbon-uneffective (production etc cost outweighing savings). But, in my loft some old futon cotton-wool sheets are stored some of which might be adapted for this purpose.

This Ducks batik has already required three or four interim boilings out, and will need two or three more before the end. I don't usually work like this, believing it goes against the nature of batik if you can't go forward with the design in one go, with only one boiling out at the end. Somehow this design got too complex. I will be glad when it's finished!

images: top - over-cooked wax; middle - new wax pellets half filling wax pot; bottom - interim stage - Feeding the Ducks batik

energy update - and carbon panic!

The Beeb's online news states that a Brit's annual carbon emissions are 2.67 tonnes (US 5.6, China 1.1, India 0.3, Kenya 0.1). My latest electric stats showed 2.8 tonnes for the year - how could this be? How could I be using more than the average person just on electricity alone? How had I not sussed this before? Further research makes the difference between carbon emissions and carbon dioxide emissions apparent...

Average UK emissions of CO2 were between 9.1 and 9.5 tonnes annually in 2005 (see here and here, both quoting from same source), which translates to 2.6 tonnes carbon annually per person. I was relieved not to be worse than average, but not for long... Monbiot's article reminded me that the goal is reducing to about a tonne of CO2 equivalent pa. There's a long way to go.

My electric usage seems to have stabilised at 2.7 to 2.8 tonnes CO2 annually (to work out yours multiply your total kwh by 0.43 for kgCO2, then divide by 1000 for tonnes CO2. Or see Carbon Trust for more info). There's not much more switching off of unused or unnecessary appliances and lights, or other chipping away I can do. It's time for substantial changes... and investment.

A joiner has advised that all my single glaze windows can be converted to double glaze - they are well-made wooden windows, only 14 or so years old and in good condition. I'm just waiting for the quote now. The past two years I'd put up temporary double glazing film, like polythene taped to the frame, and they made such a difference to heat retention that double glazing is a must. Can't think why I've delayed so long (other than house selling intentions). The studio has had lined curtains as well as blinds for the past two years, and a thermal-backed blind arrived yesterday for the (double glazed) skylight. Before the winter I want to get lined curtains up in every room.

But still all this won't be enough. Especially if Peak Gas is on the horizon, never mind Peak Oil. Paul Mobbs, whose talk on Energy Beyond Oil I went to last week, suggested 58% of domestic energy consumption goes on space heating, with water heating at 24%, lighting and appliances at 12% and cooking at 6%. My house is all electric, heating is from storage heaters (two modern, one old) with a blow-heater in the bathroom and for back-up. As I work at home they seem practical, place is nice and warm for starting work in the morning. But I have two lovely open fireplaces (sitting room and kitchen), desolate without woodburner or (wood-fired) rayburn. Apparently woodburners make storage heaters less effective - as one starts cooling down at night, the other is gauging how much work to do to get and keep the place warm - and can't help but get it wrong. Can only be one or the other. But I'm going to investigate this further... if power rationing kicks in in a few years time it's good to have an alternative ready! And I like the idea of (slow) cooking or keeping the kettle warm on top. There's also an innate good feeling from seeing/hearing flames.

Solar hot water is another option to investigate. But the shower does its own heating (very practical this time of year when luke warm is all that's needed - a luxurious 15 minute shower uses less than a unit), and there are no radiators to fill. It would be good for boiling out wax of course, but other than washing and washing up there aren't many other needs for hot water. Cooking? Coffee?

Think I'll concentrate on curtain lining and double glazing this year, and (unless I've moved) come back to technological matters next year.

procion dye shelf life

Procion MX one year shelf life? Tosh! Who started this myth? I've tested it using 18 month old magenta (red MX-8B), yellow (lemon yellow MX-8G) and black (Kenactive black K2647) and 11 month old cyan (turquoise MX-G) - all acquired at the same time (I think). They looked fine after painting, but once boiled the cyan obviously didn't fix well, as shown in the first photo. (I made the colour wheel ten or more years ago - the centre has 100% strength primary and secondary colours, with tertiaries also showing in the outer ring. The two in-between rings are primary and secondary colours at different dilutions).

I wasn't convinced by the depth of the test's black either, but serious-black always has been an issue with Procions.

Tucked away on the studio dye shelf were several pots of older dye, some even dating back to 2004 (first opened date), and some unopened pots. I was surprised to have such a collection - usually I only look when ordering new dye. There's also a stack of empty pots. Well-meaning I've intended to send them back to the supplier for re-use but haven't yet taken the final necessary step. Perhaps I should make this a little job for this week. Luckily I had an unopened cyan (though different supplier) and black (and magenta).

I ran a further test, as shown in the second photo where the year of first opening a pot is also shown. Even when painting the cyans the 2007 pot could be seen to be lighter than the 2005 and 2008 pots. To ensure it wasn't a mixing error on my part I made up a further pot of 2007 cyan, shown above the magenta where it (erroneously) says 2008 - I decided against opening a new magenta as the 2006 colour was fine.

A surprise was to find the 2006 black I was previously unsure of now looking better/darker than the old 2005 and newly opened 2008 batch. The 2003 magenta looks as good as the 2006 one, and all lemon yellows (2004, 2005, 2006) looked equally good - though as demonstrated in the colour wheel differences in tone of yellow aren't easy to grasp. For many years I have mixed lemon yellow (and advised students similarly) at a slightly higher concentration than other colours, because it seemed to need it. Perhaps I once had a 'dodgy' yellow and needed to then but this test shows there's no need to. Well that's good for resources and pocket!

To sum up, three dyes opened 18 months ago (at time of purchase) have lasted longer than one opened within the last year (also bought 18 months ago). Another dye just opened (purchased in last year?) is also inferior to that opened 18 months ago. Dyes can fix quite adequately even at five years old.

How to ensure newly purchased dye will be of a higher or equal quality to that 'past its shelf life'? I just don't know. You rely on being supplied with fresh stuff; suppliers aren't likely to tell you if it isn't.

Over the years I've bought Procion MX from three British suppliers. I used to buy cheaper dyes from one just for workshop use (when I was running lots of workshops), but wouldn't use them in my own work because the colour intensity wasn't as good. I shrugged that off as inevitable considering price difference (the 2008-opened cyan and 2005-opened yellow are these dyes, and yes I think the 2008 cyan is marginally lighter than the 2005, but not as pale as the 2007).

Maybe it all began changing when ICI's patent on MX dye ran out and anyone could then manufacture them. One company has been more open than others saying their MX is manufactured in Indonesia and naming the company.

For sure Procion does have a shelf life, though. I found out the hard way in my early years of batikking. It was a commission for a magazine front cover, with the possibility of the next two issues too. I was chuffed, flattered and very scared to have such a prestigious (and well-paid!) job to do. Very close to the deadline I went to boil out the wax - and one major colour bled bled bled! All the impact of colour A against colour B was lost - the design balance skewed and it just didn't buzz any more. There was no time to re-do it, I was too tired and wouldn't have had the subtlety for fine canting work at that eleventh hour. Devastated and despondent I had to explain what had happened. As expected they decided not to go with it despite me asking them to adjust the colours digitally back to how they were originally (at that time I had no computer and no idea whether it could be done). I felt so unprofessional... But a happier ending - some months later they came back to me - they'd decided they liked the design and would attempt colour correction. It was published but the colours they came out with were different from mine.

So... the conclusion on Procion MX dye shelf life is: demand suppliers state how old the dyes are when you buy them. Write not just the date of opening on the pot but also the date of purchase and manufacture. Test them immediately - if they are weaker than the 'old' dyes, hmmm... Don't want to fall out with the suppliers, but really I think they would need to give an explanation.

Of course, if I become a 100% woad dyer, I won't have this problem. Or rather, I very probably will but it's different as variations in woad colour will be as much down to nature and the annual crop - not wholly the grower's responsibility. Synthetic dyes are meant to be consistent.