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# David Butler's Coral

David shows off the stuff he has made for the RiAus Adelaide Reef (a satellite of the worldwide Hyperbolic Crochet Coral Reef)
by

## David Butler

on 25 November 2011

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#### Transcript of David Butler's Coral

David's Crochet Corals
The Maths Learning Centre was heavily involved in the RiAus Adelaide Reef project in 2011:
The RiAus Adelaide Reef is a satellite of the worldwide Hyperbolic Crochet Coral Reef project created by Margaret and Christine Wertheim of the Institute For Figuring in Los Angeles:
This is my contribution...
http://crochetcoralreef.org
My first coral: a pink brain coral. I began with a circle and did "crochet one, increase one" every time -- basically crocheting two through each loop. I wanted a coral as soon as possible so I didn't want to do complex counting!
A red sea anemone. The top part was made as for a normal circular coral with an increase rate of one in five: that is, crochet five and then do an extra one through the fifth loop. Then I knotted little lengths of wool through the stitches to make the tentacles. After that I started crocheting a cylinder below, increasing every so often when it seemed like I needed to make it wider. The problem was the anemone didn't stand up on its own, so I crocheted another layer on top of the one already there.
I thought a line would make a good sea slug, and this is the result of my first attempt at crocheting around a line. I started with a line of chains and then crocheted with a one in four rate of increase. After a bit I changed colours to white. After it seemed big enough, I added the antennae -- and it became even cuter!
Normally you do something like "crochet three, increase one" and it occurred to me that this means that most loops get one crochet through them but one in three loops get two. And I thought, "What would happen if you decided randomly which ones get the extra crochet?" This is the result of the first attempt. I used R to generate a list of numbers so that if I increased at those times it would be the same as randomly deciding for each loop with a 1 in 3 chance. Notice how the bit at the front left is much longer than the one at the back left -- this is because of the random generation.
Another randomly-generated one. It's still on average a one-in-three increase, but this time I went back and forth along a line instead of around a circle. I like how there's no nice symmetry in where it ruffles up or ruffles down when you do the random coral.
I wanted to try going on both sides of a line again, and I'd bought some lovely dark green wool, so it seemed only reasonable to do some kelp. I started with a really long chain and then went up one side and down the other until it seemed wide enough. I used a one-in-six increase, but efen that seems almost too ruffly. After I finished, I crocheted a little cylinder at the other end with a foot so it looked like the stalk and root of the kelp.
This one is a plain circular coral with a one-in-three increase. My plan was to have another one the same but randomly generated so I could see the difference between them.
This one is actually made of video tape. I was in an op-shop and they had a pile of videos for 10c each, and I thought "well, tape is already in a string form..."
And this is the result. It made the stangest squeaking noise as it was being crocheted, but it certainly turned out nicely!
I'm very proud of this one -- I think it looks like a pipe organ coral. Normally when you make a coral beginning with a circle you have a regular rate of increase. It's the fact that each round is longer than the one before that forces it to ruffle the way it does. But it occurred to me that if you didn't increase at all, each round would be the same as the one before and it would be forced to form a cylinder. So I tried it and it worked! This is the result of making about 30 individual cylinders and stitching them together at the bottom.
Another random one, this time around a circle. Again it's on average a 1 in 3 increase, because I that's the sheet of numbers I printed out. It's worth comparing this to the green circle 1 in 3 I did a while ago. One really cool thing is the way the fronds curl inwards when there's a length with a low amount of increases.
It occurred to me that all the corals so far are ruffly, as opposed to branchy -- and a lot of real corals are branchy. So I thought about how to get the branching to happen. I wanted to make it happen automatically by doing the same thing over and over, and I decided that instead of increasing every x stitches, I should add a chain of stitches outwards to make a new branch. So every 9 stitches I added a chain 4 stitches long and then began crocheting back down the chain and along the edge, counting 9 from the top of the branch before doing it again. This is what happened.
This was an attempt to make a coral that was "bumpy". I thought if I increased a lot within one stitch then it would make a bump, so this one is made by crochet-5-increase-3 (which actually means do ordinary crochet for the first 4 stitched and then 4 crochets through the next). Anyway, I didn't get bumps, I got corners. But it still looks cool.
Another branching one. This time the branches are 8 chains long, and I count 13 from the top of each branch before I add another one. It looks a lot more tree-like, but I reckon even longer branches and longer between them might do even better.
I did this one at the MERGA conference, and attracted quite a bit of attention! This time, instead of increasing every five, I made a chain 5 links long and then linked it back into the same stitch at the bottom. It turned out quite bumpy, which is what I was going for.
I'd been working on this one for quite a while and I finally finished it just before the coral workshop at uni. It's another branching one -- add a branch 10 chains long, then down the branch, then crochet five, then add a branch etc -- but this time with videotape. A plain crochet of red wool around the edge makes it look really really really cool!
After going round the edge of the one just before in a different colour, I thought the previous videotape one would look better if I wend round its edge in another colour. So here's the new version. You can see the edge of the coral now, which is nice. That green is a kind of plastic string I got from a cheap shop, and I was very lucky that it was just the right length to do the job!
I'd been thinking about how to achieve a "fan" coral and I thought that videotape had the stiffness to do the job. So I crocheted six long branches joined at the base and then joined them together with a continuous network of chains. This is all with single crochet -- what the Americans probably call "half" crochet. Then I crocheted in some florist's wire to help it hold itself up.
Another attempt at branching. This time with treble crochet so that all the branches are thicker. It produced all these cool knobbles. I was going to go round the edge in another colour, but the knobbles flattened out when I tried it, so I undid it and left it black.
I decided to finally try crocheting with two strands of wool and this is the result of a one in two increase. I was also told I should be crocheting through both loops rather than just the one as I'd been doing previously, so I tried that too. The coral turned out to be very stiff and heavy -- as you'd expect coral to be!
Yet another attempt at branching. I thought a truly fractal approach might work, so I began with a chain, then crocheted down and up and when I reached the top added two branches, then went back down. Then I went back up and added two branches at the top of each of the existing branches. Then again and again, adding two branches at the top of each existing branch each time. All the crochet is single crochet. I really like how it looks properly coral tree-ish.
I had this rainbox wool from the start and I really wanted to do something with it and this is the result. I made a long chain and then crocheted at different rates back and forth. The right-hand end is one in one, then one in two, one in three etc down to one in seven at the left-hand end. I had little strands of wool in a different colour to tell me where to change the rate which I pulled out when I finished.
Another stiff one -- one in three increase around a short chain, with blue and white wool. Then a couple of rounds with just the blue when the white ran out.
This jellyfish is a combined effort of me and my daughter Kaylee. I taught her to crochet at the beginning of the project and she made lots of colourful chains. She did make a coral, but she couldn't part with it, so I crocheted a hood to join the chains to and presto! -- a jellyfish.
And this is the final coral I made for the exhibition, finishing it on the train ride into the city on the final day for submissions! I saw something similar the previous week at RiAus and wanted to give it a go. It's actually an ordinary circular coral with a one in three increase, but at the end I drew up the ruffles and stitched them together.
Open from 5th August to 7th September 2011, at the Science Exchange of Pirie Street Adelaide. Open 10am to 4pm Weekdays, and till 8pm Fridays.
And now for the exhibition...
BUT WAIT! The reef will return again, so I made more...
This is the "scarf" I made to wear at the exhibition opening. It's a slow rate of increase -- one in six I think. No-one believed me that I'd made it myself!
Another videotape branching coral -- but with yellow wool around the edge. I alternated between doing long branches and short branches with this one, to give a more random effect.
I had been talking to people at RiAUS about cellular automata -- where the simple rule of what to do is based on what was there -- and I thought that multicoloured wool could do the trick. With this one I increased when the wool was pink. In the end it acheived the same effect, but it did mean I didn't have to count!
Another cellular automata one -- this time I went round a line and increased when it was green. It had the tendency to make the colours clump together, which I liked.
Another branching one, but this time with really really long branches. It's really floppy, but does have that real corally look I think.
I'd been wanting to use this blue-flecked white wool for ages, and I thought I could do the cellular-automata approach. With this one I increased when it had any blue in it.
And this one I increased when it was purely white. The different level of crinkliness is caused by the fact that there is more white than blue, so I had to increase more often
I wanted to see if I could make the branching coral stand up, so I did this one with multiple strands of wool. The final row is done with a single colour. The effect is quite impressive -- you should see what it feels like!
I tried a lot of different things with this one: I used a much smaller hook size, and thicker wool so that I could get a stiffer coral. It really feels solid and holds its shape very well. I also used a system where I did no increase for four and then three in each for two. This gave it a bit of a kink every so often which made it do this cool back-forth crinkle.
I did this one at our second coral workshop here at the Uni. I used three strands of fine cotton and a very slow rate of increase -- one in twelve. With such a slow rate of increase, it takes a long time to escape the "cylinder" shape and start to crinkle. In the end it looks a bit like one of those sea-sponges.
It was time to try another videotape coral. This time I used a 1 in 5 increase, and put my hook through book loops (rather than just 1 as I usually do). Interestingly, even with the slower rates of increase, the coral still curves and crinkles a lot if you do it long enough.
After thinking about my crochet-when-it's-a-certain-colour rule, it occurred to me that you could mark the wool yourself to acheive the same effect. Then the wool itself tells you when to increase, rather than your counting. So I marked some cream wool with a highlighter at random intervals, then increased when there was a mark. This is the result. It actually turned out quicker in the end than actually counting.
Our final workshop was on the way and I wanted something to show people how to get there. So I made this. It's a long chain and then every so often I did a little coral with a 1 in 1 increase. The distance between them is pretty much random, as is the size of them. But it really was totally awesome, I think.
I made this one at the final workshop here at Uni. There was some lovely soft thick variegated wool, which I though would make a nice soft-but-stiff coral. This is the result of increasing whenever the loop was purple.
The RiAUS asked for brown, so I set to work on some brown corals. This one is a combination of branching and a one in four increase.
After seeing the effect of increasing and branching together, I wondered what would happen if I branched on one whole row and increased on the next. To make it easier I switched colours when I switched style -- but I didn't tie the two colours together, I just used two balls of wool at once and when I got to the other strand, I worked it in. I think it turned out ok.
On the previous coral, I switched colours to make concentric "circles", but it occurred to me that I could also just keep the two strands independent of each other and make a spiral. This is the result of the first attempt (but I ran out of the brown and finished it off with just orange).
Another spiral, this time both colours increasing at a rate of one in four.
After the cream-and-pink coral I made by marking the wool, I had begun to mark some orange wool and I decided to finally finished it. I began with a line and went round it, increasing when I saw a black mark in the wool. The overall effect is about a 1 in 3 increase.
I decided to keep investigating spirals, and for no particular reason I chose to add branches on one of the colours. I didn't go around the branches with the next row, but crocheted across the base. So the overall effect is an ordinary coral with knobbles all over it. Deliciously ugly, I think.
I decided to see what would happen if I increased at two different rates with the two colours of the spiral. The pink is increasing at one in two and the purple is one in five. While doing this I wondered how to calculate the resultant "average" rate of increase, and created a formula to do it. This one therefore comes out to a rate of one in 2.9.
While only a short way into the previous coral, I had the idea that I could actually increase on one colour and decrease on the other! I was so excited I tied off the one I was doing and made this one. The pink is a one in one increase, and the purple is a one in two decrease. According to my formula, the average increase overall is about one in 6.5.
Even though I had decided not to do any more on the night before the coral due date, I just couldn't resist doing one final investigation on the train journey in. Both colours increase at one in four, but the dark brown is double crochet and the light brown is treble crochet. Overall it looks like a one in 6 double crochet. I particularly like the cookies-and-cream colouring.
And now for the SECOND exhibition...
Open from 9th December 2011 to 2nd February 2012, at the Science Exchange of Pirie Street Adelaide. Open 10am to 5pm Weekdays, and till 8pm Fridays.