Some photos taken of the process of casting with glass wax- the melting glass wax, the casts full of glass wax, and photos of the failed jaw bone casts and brick cast. Casting the brick hollow with glass wax is proving troublesome- the wax is very brittle and the sides of the cast keep breaking as I try to de-mould it. I will try one more time to cast it hollow but a bit thicker and if that doesn’t work I might have to cast it solid instead. The jaw bone pieces kept failing as the glass wax is too thick and not hot enough to flow all the way through the moulds- I will try to get it hotter next time, but I have to be careful in case the wax gets too hot and the colour changes.
Video demonstrating the properties of glass wax and the casting process.
I wanted to explore the properties and materiality of glass wax, and these are the results so far.
Clip 1: the chunk of unmelted glass wax, demonstrating what it looks like before it is melted and cast- you can see how the light refracts and passes through it.
Clip 2 and 3: the glass wax as it melts, showing the viscosity and how it stretches and flows much like real glass when in molten form. It is very different to other waxes I have used in the past.
Clips 4 and 5: the first attempts at casting the jaw bones in glass wax- as you can see the wax didn’t flow completely through the moulds as it was not hot enough and cooled too fast. I will try again but with the wax much hotter so hopefully it will flow through the moulds properly.
The rest of the clips: the other bone casts in glass wax.
These photos show the second attempt at casting the jaw bones in glass wax (still not hot enough), the glass wax casts all together, the broken hollow brick cast (the details were captured beautifully, it’s just a shame that the sides broke), and one of the glass wax casts lit by Jonathan’s phone torch- as an experiment to see how light travels through them. I think going forwards I would like to photograph the glass wax pieces with a light source beneath them like this, but using a more professional set up.
Notes on glass wax:
- Properties- melts differently to waxes I have used in the past (i.e. the green and orange waxes used in uni, soy wax, paraffin wax, beeswax)
- As it melts it goes quite stringy and is still very thick and viscous, can be stretched into glass-like threads that look like nylon thread
- It sets VERY quickly and needs to be quite hot to pour well, but you have to be super careful not to overheat it as it can make the wax change colour
- You can add oil paint as a pigment to glass wax, but I’m more interested in how it looks originally- like a translucent glass
- I might do one or two in colour just to see what it looks like, but we’ll see
- It is quite brittle- I tried to make a hollow brick cast and the sides shattered (like glass) as I tried to remove the cast- if I retry this I will need to make it thicker
- It picks up detail really beautifully and I’m definitely impressed
- I need to redo the jaw bones in glass wax as the wax wasn’t hot enough and as a result didn’t flow through the moulds properly
Today I got the third and final rose ran up, then attached to the cup with the rest using hot knives and wax. Then I painted a layer of shellac over everything, to help the grog to stick to it, and once it was dry I covered it all in first coat grog.
Once that had set we put the plastic cylinder over it all, and I layered scrim (netted fabric) and plaster along the bottom, to seal the cylinder to the board, and around the middle of the cylinder for stability. As soon as this was set I spent the rest of the afternoon mixing and pouring second coat grog, to fill the entire cylinder to make the mould ready for the kiln.
Really proud of my progress today! Got loads done, and worked hard to get the mould ready for the kiln. It doesn’t look like I’ll have a chance to pour before the break, but at least when I get back it will be all ready to go.
I am putting the leaves to one side for now, they have been dipped in wax so they should stay in a usable condition over the break. The above photos show the process of prepping the wax dipped roses to go into a plaster mould- Lindsey was showing me how to do it in a different way from how I have previously made moulds with Becky, essentially working the opposite way round- you can see one of the roses attached to the cup, and the cup attached to the board. Once all three roses have a system of runners and risers they will be attached to the cup in the same way. The next steps will be to degrease it all, put a cylinder around the whole structure, and pour the plaster mix into it to make the mould for the kiln.
I have decided to focus on the roses as I realised that the roses will go beyond simply being a gift to my mum and my nan. I began to think about the ideas behind preserving something that is normally fleeting- roses die and dry out quickly, yet the bronze casts never will. Not only will they outlive any real flower, but they will outlive myself, my mum, and my nan, too. I was inspired by my classmate Gabby’s documentation of her family, and I think I would like to photograph each of us individually with a rose, and then as a group, to capture the moment of gift giving in time, much like the roses are being frozen in time by being cast in bronze. I have also been thinking about how, in time, I will end up with all three roses- my mum and my nan will at some point no longer be around- so it is almost like I am loaning them to my mum and nan, knowing that one day I will get them back. It is a reminder of our own fragile mortality, and also raises the question of who will inherit them when I die. I chose roses as they have a particular significance to my mum- they were my dad’s favourite flower and since his passing she has always bought yellow roses for special occasions, and when she is feeling low, as a way to feel connected to him and his memory. My nan and I frequently buy my mum yellow roses when she is feeling down, and it is my intention to try and patinate them a yellow colour, if this is possible.
- discuss the idea with my mum and nan
- get the roses into a mould ready for the kiln
- ask Gabby for some photography pointers, if she has time. I really admire the sentiment behind her projects, but also the way she executes the photographs is really beautiful, and I am not very experienced with photography so I want to ask her some technical questions about lighting and such
- look at Louise Bourgeois work- her work often deals with her feelings surrounding her own mother, and a lot of her work is also sculptural so it is a relevant reference
- Made up a batch of herculite for my hot rubber moulds- to demonstrate the process I am going to leave them exactly as they came out of the moulds
- I made sure to wiggle the moulds as I poured to make sure the plaster got into every crevice
- The bones came out beautifully but the brick broke as I tried to de-mould it, clearly the sides weren’t thick enough
- I could make the brick solid instead of hollow but herculite is super heavy, and if I am trying to show the process it should be hollow to match how I made the wax cast
- I will make a thicker hollow cast of the brick later on this week
- I wanted to get into the metal workshop today but I felt really sick and foggy so Lindsey and I decided it was best for me not to use the power tools today. I didn’t want to waste a day, so that’s why I made the herculite casts, as a way to still be productive
I also ended up going on a walk to the flower shop in Camberwell with Ellen, a BA Sculpture 2nd year student, and we are going to be doing some bronze casting together. We are both interested in nature, and capturing fleeting moments (and both want to make Christmas gifts for loved ones) so we bought flowers from the shop, and also collected foliage on the way back. We then dipped those in wax, and the next stage is to use a hair dryer to set the wax, and then we can build the moulds- the plants will burn out directly in the kiln so there is no need to make hot rubber moulds and waxes. The wax will help to stabilise the plants and make them a bit thicker, so that they will be more likely to come out in the pour. I know it isn’t directly related to one of my projects but this is something I’ve wanted to do for a while and I feel like I might as well give it a go whilst I have the opportunity.
Once the moulds had been poured and removed from the sandpit they next stage was to cut off the plaster coating, with a saw, and then smash open each mould with a mallet. The above photo shows one of the bronze casts, mid smashing. The aim was to remove as much of the plaster as possible, which was then smashed and ground up into powder, to be reused for further mould making.
This video shows part of the clean up process- once the casts had been removed from the mould, the rest of the plaster still needed to be removed from around the casts. It has been sped up by about 250%, as the original video was 20 minutes long, and I wasn’t sure if anyone would want to watch it! As they were too big to be secured in a clamp at this point I had to secure them with pieces of brick, so that they were stable enough to use the hammer and chisel on.
Once I had gotten rid of as much plaster as possible with the hammer and chisel I tried to cut off some of the runners and risers using an angle grinder, which shook some more of the plaster loose. Before I could cut any more of the excess metal off I had to take them down to the print making studios and blast them with the pressure hose, not pictured because I got very wet!
Health and Safety: I had the extractor fan on, and wore gloves, a visor, ear protection, a dust mask and an apron
Before the moulds could be fired in the kiln, Becky removed the plastic from the outside (that we had used to make the moulds, as seen in previous posts, and the brick video). We then had to cover the sides and bottom of each mould with layers of scrim coated in plaster, to create a protective barrier to stop the plaster moulds falling apart in the kiln- four of us did this, and I didn’t take any photos as it was very messy! But you can see the moulds with their plaster coating in the above photos. The moulds then went into the kiln upside down, as you can see in the photos. They go in upside down so that as the mould is heated and the wax inside melts it will flow out of the mould, leaving empty spaces where the metal will then be poured.
The next step was to vacuum the insides of the moulds to ensure they were free of debris, ready for the pour. Once this had been done the moulds were ready to be winched into place using the pulley system in the foundry, and set up in the sandpit ready for the pour.
The video shows the technicians winching one of the moulds into place, I kept out of the way for this part as I hadn’t done it before and wanted to watch and make sure I knew how to do it for the next moulds. I then had to dig the moulds in, making sure the sand was packed in closely around each mould to ensure stability for the pour. To keep the moulds clear each one had a piece of wood placed over the top.
This was definitely one of the more arduous parts of the process- it took five of us to do the plaster coating, and four of us to get the moulds from the kiln into the sandpit, as each one was incredibly heavy and fragile. I was careful to follow all instructions from the technicians to make sure nothing went wrong!
I was worried that the process might be unclear from the step-by-step and photo posts, so whilst making the brick moulds in July I recorded video clips, as well as taking photos, to better showcase the lengthy process behind casting in metal in the foundry.
This video shows the process of putting the wax bricks into plaster moulds, ready to be fired in the kiln. This stage was the lengthiest part of the whole process, and shows at least 3 weeks worth of work in the foundry- whilst waiting for layers to dry I was also working on the wax bones and prepping those using the same process, to make the best use of my time.
Unfortunately some of the clips are poorer quality than others as they hadn’t automatically backed up on my Google Photos, so I had to download them from my Instagram instead. Going forwards I am going to be much more careful about backing up my documentation. I was also a bit under the weather at the time of recording the audio for this video, so I am a little bit breathy, and stumble on my words a bit, which I have tried my best to edit out. This is actually the 3rd attempt at making this video, as the first and second time it didn’t save properly, but 3rd time’s the charm!
On another note, I am deeply sad that Becky, the foundry technician, has moved to teach at Chelsea as we got on really well and she has helped me a LOT with this project. Good luck at Chelsea Becky, we’ll (I’ll) miss you!
Casting the jawbone raised a host of issues that I didn’t realise would be a problem, but hopefully it will work out in the end. Before we could make a hot rubber mould of the jawbone Becky (the technician) and I decided to make a plaster cast of the jaw, as we felt it would be too fragile to make a hot rubber mould from directly.
- Before we could begin casting I had to fill in the holes in the jaw (where the rest of the teeth originally were) with soft wax, so that it would be easier to cast. I also used a little superglue to secure the two teeth- we were worried that they may have come out of the jaw when we de-moulded it, so this was a preventative measure.
- I then pressed the jaw carefully into some clay and built up clay walls around it, and then applied a few layers of vegetable oil to the jaw to help release it from the mould once the alginate had set
- I mixed up a small amount of quick set alginate which I poured into the clay mould and left to set
- Once this had set I carefully removed the clay and rinsed the jaw and alginate, before greasing it up with more oil, and building up clay walls around it
- Another batch of quick set alginate was then poured over this, and left to set
- The clay was then removed, and the two halves of the mould separated and the jaw carefully removed.
- After cleaning both halves of the mould I fit them together and secured them with elastic bands, and was then ready to pour fine casting plaster into it
- The first attempt didn’t work very well and only the thickest section of the jaw came out, so for the second attempt after pouring in the plaster I moved the mould around to encourage the plaster to flow through the whole mould
- Once I opened the mould up I realised one half had not worked out, and the other half, where all the detail was, was too thin- to fix this I cut up scrim and layered that and some more plaster on top of it until it was thicker and stronger
- I then de-moulded it and created a hot rubber mould from that plaster cast. Because the detail was lost on one side I decided to make a flat mould, rather than a round one that needed to be cut open, to save materials
- The final photo on the slideshow is of the original jaw, first failed plaster cast, second plaster cast, and de-moulded wax cast of the jaw- as you can see there are a lot of details that need to be worked back into the wax by hand, but I am confident that it is doable
Photos of the wax casting process- melting the wax in a saucepan before leaving it to cool to pouring temperature (the wax needs to be cool enough that it coats the side of the pan), then pouring into the secured moulds, including the larger brick mould, before de-moulding and removing excess wax/working the details back in.
Video of two wax casts, fresh from the mould- you can see that there is excess wax that needs to be removed, and some of the details need to be worked back in to the casts.
Video made up of a clip showing the second, larger batch, of wax casts fresh from the moulds, followed by a clip of me working on one of these casts to remove excess wax and work a hole back into the cast to mimic the original bone. The final photo is of the wax cast from the previous clip next to the original bone I cast it from- you can see that I have worked some of the details lost during the hot rubber mould process back into the wax cast.
The two clips in this video show the first hollow wax cast of the brick I found on the river, and the second cast next to the original brick- you can see how the hot rubber mould picked up most of the detail from the brick, and how that has translated to the wax casts. You might notice some lines on the casts- this is because to make a hollow cast you need to pour in the wax slowly and roll the mould gently around to ensure the wax coats the mould properly- I did this too slowly so there are lines visible. Next time I use the mould I will be careful to pour the wax faster to avoid this happening- I may melt these two casts down and redo them. The brick casts need to be hollow as to make a solid bronze of that size would be too costly, and too heavy. I will either have to leave the hole in the bottom, or weld a small piece of metal over the hole, but this is something I will tackle when I get to that stage.
Unfortunately this was all I was able to get done before the workshops closed for the break, but I am looking forward to getting back into the foundry/plaster room and continuing my work! The plan is to make at least two of each bone in wax, and then make at 2 – 4 large moulds to go into the kiln and then be poured, as I want a copy of each bone in aluminium and in bronze. I have also been shown a material called glass wax, which is used in the film industry to make objects that mimic glass, and if I can afford it I would like to experiment with this medium as well, as it will give me another material and colour to analyse.