Sunday, 31 August 2008

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.

Wednesday, 30 July 2008

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.

Wednesday, 16 July 2008

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

Wednesday, 9 July 2008

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.

Tuesday, 24 June 2008

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.

Friday, 20 June 2008

waxing relief!

I was getting so despondent - why was I waxing only wobbly lines not smooth ones like I used to. I even bought Green&Black chocolate yesterday to see if that helped. I cleaned the canting (boiling all of them in water and poking the spouts with wire) and changed the wax (I wasn't sure how old or how cooked the previous lot was, but could tell from the colour and depth in the bowl it wasn't that new). I wondered if my worktop had originally been made for me working in shoes (I'm usually barefoot in the studio) and so tried with my flipflops on, half or an inch taller.

I tried changing position. I tried changing tool. I varied working from left to right (over the curve) and up and over to down and under. I tried every variable I could think of.

Suddenly I got it. Suddenly it was happening, suddenly smooth curves and smooth lines and I could follow the pencil lines easily. Oh joy! I was so happy and felt like celebrating! And I have no idea what I did, just that it all came together.

So... I had to go-for-it and do those not-at-all-scary-now spirals for the birds batik (see yesterday's post). I did them straightaway, and they are fine! A doddle!

Such a relief! I thought I'd need to practice for days to get that knack back!

Yee ha! Big smile! Chocolate time!

Thursday, 19 June 2008

waxing

The woad is growing nicely now, and it's time to get waxing to have something ready for dyeing. Here's one just finished, taken from a sketch of the Brown Willy skyline (Cornwall's highest peak) at sunset from a favourite perch, Black Rock. Because woad-dyeing will be a learning process I want to keep the first ones simple in terms of waxing - so less wax is wasted on (possible) disasters. A series of batiks of moorland peaks may not be particularly creative or ambitious but is a nice excuse to get out for some longer walks than I've been doing lately! Also, being nearly midsummer, my mind turns to our inherited stone circles and other monuments with solstice and equinox alignments. Roughtor (second highest hill) was, apparently, very important to our Iron Age forebears. So respecting their beliefs and knowledge by focusing on views of Roughtor from prominent peaks and places doesn't seem quite so shallow after all, and maybe I will learn something too.

Minimal lines will also help me get a feel for predicting balance of (should I call it 'colour' or 'tone'?) after dyeing - the impact white lines in a deep blue will have. At least I hope to get deep blue!

Also, as many of my past batiks have treated wax as though there's no tomorrow, literally swamping the cloth with it, I need to start from the opposite extreme of less is more. I do now recognise there are limitations to the amount of wax I should use per batik, as there are limitations to the amount bees can be expected to produce annually (on the one hand) and availability of paraffin wax relates directly to availability of oil stocks (on the other). And production of paraffin wax contributes to global warming, but all-about-wax is for another post another time.

A new problem hit just after I'd waxed this piece - where to store it? Up until now I've worked on just one or occasionally a few related pieces at a time - waxing, dyeing and finishing - before moving on to the next. But not now... I will need a number of pieces ready for the woad and then do the dyeing in a batch. The cloth can't be folded and put in a drawer - the wax would crack on the fold lines. It really needs to stay flat. My mind sees it hanging from one of those coat hangers with clips on but I don't have any, nor a bound-to-stay-clean and unlikely-to-get-bashed (=cracked wax) spare hanging place in the studio, or house. I'm trying to approach this sideways, hoping tangentiality will let the obvious solution slip into view.

There's another reason for waxing these pieces now. Before I start any woad dyeing I need to finish the birds batik mentioned back in January and to do that I need to get some canting practice in for very long smooth curved lines - requiring a move of the whole body in sync with the line. Like all craft skills, you have to keep practising - stop for any length of time and you get rusty. Like me. The design calls for two perfect spirals within the white circle - any imperfection would just kill the picture. So I'm nervous and need to get confident before starting.

I also mixed up some Procion dyes yesterday and am running a fastness test on them. Three of the colours were first opened about 18 months ago, theoretically past their shelf life, the fourth is about a year old. I really don't want to buy new Procions just now... but the thought of having to re-wax because the dyes didn't fix is too scary!