Monday, September 24, 2012

Blurp, Blorp, Smoosh


Last week I took a class. An awesome class.  A class that makes you glad you're an adult who has finished regular school so you can spend a whole week doing this sort of class.

A class, in short, in mould-making and casting, skills which are very useful to my Props students and which I, until quite recently, had absolutely no hand in. But no more!

Yes, I, your humble narrator, am now absolutely teh awesomzors at pouring silicone on knick-knacks.

I've uploaded photos in chronological order, starting with Tuesday, as I forgot my camera Monday. I had a classmate and a teacher, but in the interest of courtesy I have excluded photos of them and their work as I don't really know them. But their work was quite good--in several instances, better than mine. Anyway.  The shot at the top is at home this past Saturday at dinner. You'll see. Pictures!

This is my 3D mould of a candlestick the morning of day 2. The original candlestick is encased inside. By this point I had poured and smeared silicone all over one side, and had let it harden overnight. I then made a trough around it and filled that with plaster, which sets up quite quickly (less than half an hour). The little dots help everything line up when you're reassembling it. The plaster jacket poured around it holds the silicone mould in the right configuration while the casting medium sets. Everyone catch that?

Your humble narrator MISSING A HAND OMG WTF AAAAA  graciously volunteered to demonstrate how Alginate works, an algae-based form-taking compound that typically works exactly once, but very quickly. Only used for safely taking moulds of people's parts, you slorp it on fast (and cold!) and let it set (in about three minutes). Then gently remove (in my case, I wiggled my fingers and it came off) and fill with plaster within an hour to get an amazing copy.

My hand, supported in rice, waiting to be filled with plaster.

Not bad, eh? Embiggen for detail. The alginate mould was, unfortunately, destroyed in the process of removing the plaster cast, but that's normal. Now I could mould the hand in silicone, which takes at least 8 hours to set up, without my fingers cramping up for 8 hours. 

My original candlestick, with its freshly-cured and freed plaster shell, waiting for its second silicone layer.  Neat thing: with enough petroleum jelly, the silicone and plaster you see here will not stick to the silicone and plaster you pour to make the other side, so the dots just form themselves! Poured second silicone layer and put aside.

Cookin' up some vinyl. Yum. It smells like custard-scented plastic, particularly so when you  melt it.  It gave me a headache.

My classmate pouring vinyl over an ashtray she would like to use as a lamp base. The vinyl takes a couple of hours to cure, so we left these overnight.

Wednesday morning. The brass-coloured coin on the right is the original, found in a pencil-box in my house.  I think it belongs to my landlady, though what its significance is (if any) I couldn't begin to guess. The yellow form above it is, you guessed it, the vinyl mould. The terracotta-coloured mould and block above are modelling wax (very very soft, smearable, smells like crayons) and the off-white set are Sculpey.

Wahoo! After a quick plaster-pour and set in the morning, the candlestick decanted beautifully. Silicone is amazing--it even copies the sheen of the original. The belly of the knick-knack is ever so slightly satin-textured, and that will reproduce accurately no matter how many times you use it (which could be an indefinite number with reasonable care). My classmate's prototype was glossy ceramic, and it transferred the gloss perfectly.

Cutting air-vents into some fiddly bits to prevent bubbles getting trapped. The vent must carry straight through into the rest of the piece.

GIANT CHRYSALIS. Or mould wrapped in cling-film ready to have plaster poured in it and shaken vigorously. 
Plaster poured, time waited, cracked open, success! Well, not really success--I mixed the plaster too thick and it set up a bit too fast, so there's more bubbles than I would have liked, particularly near the bottom (the last part I poured, by which point the plaster was already setting up.) Whoops.

But hey, my air bubble vents worked! Everything seeped out nicely.

Cleaned up and tidied. Did you know you can cut freshly-cast plaster with a scalpel? I do now. I finished up the bottom later.

As a curiosity, my teacher coated the handle in a thick paste-like silicone and let it harden over night, just in case. It came in handy. We also poured 2D moulds in silicone and left them overnight to cure.

Original at the bottom, while the top two are a study: both copies are made with a plaster compound mixed with iron for strength (and to give it a nice terracotta appearance) but they are resting on their moulds--vinyl to the left and silicone to the right. Embiggen for detail--you'll see that the vinyl one looks nicer, nice and smooth, but the silicone one, while rough and kinda crappy-looking, is actually a perfect copy of the original. Vinyl doesn't take absolutely the best copies of things, but it has three very distinct advantages over silicone--it is slightly cheaper, it sets up faster, and it can be melted down and re-used over and over. But silicone does the job far better.

Thursday morning. A shell being copied in polyurethane resin, padded out with Fillite, a lightweight industrial ash that is used to stretch polyurethane (as a cost and weight-saving measure). This process involved swirling the plastic resin carefully around the mould until it hardened (well, until it stopped moving).  It sets up in about twenty minutes. 

The shell to the left is pure polyurethane, no filler. The shell to the right is pure...shell. With some barnacles. But they're long dead. My landlady had about eight of these.

Check those deets! Polyurethane's potential for producing accurate replicas is OFF THA CHAIN. 

My teacher's genius idea for adding increments to disposable cups. Only works if you regularly use the same cups, of course, but this style is pretty easy to find, and dirt cheap. Great for polyurethane and polyester mixing. 

Oh dear, this is getting a bit silly. Original at the bottom, then a polyurethane copy with faux gold leaf powder added to Part A. It was lightweight and shiny but the gold comes off if you rub it. Then a polyester copy, filled with actual bronze and copper powders. Quite heavy, and polish-able to an antique-like glow. Then the two terracotta plasters, then wax, then a cruddy polyester one from the vinyl mould (made with leftovers, hence it is not full), then sculpey, then polyurethane/gold leaf in vinyl (again, leftovers). It gets worse.

Now it's your turn!

A polyester/metal powders apple, using a mould that was laying around. I've polished it a bit with steel wool to bring out some highlights. It is very cute. This was Friday morning.

A polyurethane copy of my candlestick's handle, with green pigment and faux steel powders mixed in. The steel just darkened it, really, which I think gave it a slightly antique-y feel. It was an experiment. As you would have noted earlier, polyurethane cures opaque, so suspensions in it don't show up very well.

Set handle copy in the mould for hollow cast attempt. The hollow-mould technique probably would not have gotten enough PU into the handle space for it to work otherwise.

Photo down the bottom of the mould to check how it was all curing in there.  Looks good!  Hollow PU casting involves rolling it around and around and around and around until it stops moving. Takes a while but it saves money on resin, which isn't cheap. Pretty much nothing involved in the mould-making and casting process is cheap.  The copy came out really well but I forgot to take pictures of it and my camera battery is dead. Maybe I'll update this after I take a picture. 

So yes, I learned something. A thing or two. I learned a lot of other things that aren't detailed here but these were some of the cool things. I also really enjoyed it. I screwed up a few times but was able to figure out what I'd done wrong (mostly speed and thickness-related issues that get better with practice).  The things I brought home look nice, and I'm proud of them, though what on earth I'm going to do with them now I have no idea. I'm back at work this week, ho-hum. Maybe next summer I'll take a class in ceramics. Or sculpture.  Or blacksmithing. Or silver-smithing. Or painting nudes. Or painting naked people.

MOAR! Just two--the middle ones are Jesmonite, a type of plaster that is mixed with a plastic polymer for added strength. The yellow one is Jesmonite with chrome yellow pigment powder, left over from my classmate's hollow cast. By the time I'd made my 10th copy I was giggling like a moron. I'm rich! I'm rich! I'm awaiting the arrival of my clear cast polyester copy, in a translucent blue with glitter. (classmate's idea). It wasn't set up by the end of class Friday so the teacher said he'd put it in the post, along with my vinyl mould and a few other things we poured.

Monday, September 17, 2012

The Power of Nonsense

This post by my spouse and other current events in the lives of my family members have spurred a frustrating line of reasoning in my mind today.  When we don't have a clue what's going on, when we have no means of influencing what happens to us (with regard to a particular desired objective) the human brain has a funny tendency--it tries to draw cause/effect relationships between utterly unrelated factors (which will either help or hinder the progress of the objective).

To expand off of Ben's example, our attempts to fake out the bus gods were unsuccessful nearly all of the time, but the one or two occasions when walking away from the stop actually did coincide with the bus arriving reinforced the notion that it was worth a shot. We probably would carry on trying our pointless summoning dance, getting more and more frustrated and convinced the universe was out to get us, if the opportunity to gain relevant information had not presented itself on the always-open public transit website on my phone. It is this access to live bus locations alone that has prevented me from ever downsizing back to a dumb-phone. The bus tracker provides not only invaluable information--it is a reminder of the existence of information, a souvenir from the day I stopped feeling helpless to TFL's whimsy.

It is a pure, simple example of the triumph of understanding over superstition. But understanding is not inherent, nor is the relationship between cause and effect always obvious. In my instance, the failure of the bus to arrive on time, or within its expected time-range, could have a whole host of causes--from heavy traffic, to a passenger-related incident on the bus, to a drivers' strike to the fire-bombing of Catford by the disgusted city of Greenwich. All I know is that I don't have a bus when I should. A more inquisitive mind than mine might be inclined to undertake a simple research project to this end. Perhaps one might catch a bus heading the opposite direction to inspect the route the desired bus should be coming through. If the route appears clear, perhaps they could contact the depot to enquire if there has been a bus breakdown or a sick driver. Once they're told off by the depot receptionist they could check a newspaper about that all-too-possible strike. There is plenty of information out there waiting to be discovered for the patient, unperturbed passenger with nowhere in particular to be. If you follow the scientific method, more often than not you will figure out what the hold-up was.

Or you could do the impatient-commuter version of a rain dance.

If, like me, you are too chicken to annoy a bus dispatcher, too desperate to get where you're going to try going another direction purely for the sake of inquiry, or too trusting in your state to believe the drivers would do such a horrible thing as leave you stranded on the side of the road, you'll probably just stick to rain dances. But why is this? Is it intellectual laziness? Faith? Something else equally as childish?

I tend to think it is somehow related to my capacity for empathy, albeit perhaps a capacity which has developed far beyond its usefulness. As a feeling, reacting entity who has grown up (and on a larger scale, evolved) within communities of other feeling, reacting entities, I seek to place myself within my environment--establish how I relate to the people, objects, and events going on around me at all times. It is entirely likely that, as I have observed how my actions have affected other people and theirs in turn have impacted me, on a less-conscious level I have attempted to apply my understanding of this relationship to my other environmental elements (that is objects, events, and other non-person phenomena). Perhaps the inner baby in my head, still thrilled with herself for figuring out how to fit all ten toes in one mouth, assumes that I should be able to affect anything that affects me. "Surely, if the bus can make me late, I must be able to do something to make it early!" Furthermore, this same dribbling, grinning moron, lodged firmly near my medulla oblongata, who was the centre of the entire universe for about two years, sincerely believes that anything which has affected me must have been meant for me personally, be it a hurricane, a found dollar, a pleasant breeze or a late bus. This has compounded with the beautifully-crafted sense of white-kid guilt instilled in me by the South Carolina Department of Education to force my default assumption to be, whatever negative happen-stance befalls me, I deserve it, either because I'm a horrible person or because I don't appreciate the nice things I have. "I see. I accidentally smushed that snail but was more disgusted than sorry, so this is my punishment. No bus."

As I meander through my everyday, I realise that the ol' thinker in my head is making a lot of junk up to either make sense of, mitigate, or disappear from view the billions of unrelated events that make up the world around me. I want everything to be linear, despite the fact that it rarely is. I want effects to have obvious causes, I want to know why and how things happen, and I want to be able to control the factors which nevertheless control me. In most ways we are completely helpless, the hovering end of the slinky which has no idea that it has already been dropped. But rather than acknowledge this--an acknowledgement which has surely landed more than a few people in quiet, padded rooms--we attempt to control, or perhaps pretend to control, everything we can. The rain dances don't work, and on some level we are of course aware of this, but without access to genuine understanding of what the hell's going on we can either embrace the nonsense or the crushing futility of existence.

Oh these things always spiral downward rapidly.