I decided to make a paper model to cast in sand using the adaptive formwork technique. I chose to use the digital site information from my studio project and make it in scale 1:500. The final model would then be approximately 70*50 cm. I used a type of 300 gram paper to cut each height level and the same type of paper for the 2mm height difference for every curve. The model was then assembled using tape.
For casting with every level in the correct height I cut out several mirrored sections from the site to support the paper model from the bottom of the bounding box. The thought was that I would use these sections to level the sand underneath the model to get everything in the right height. This didn’t turn out well because the sand didn’t hold to this grid of sections.
I therefore shaped the sand through pushing and shaking the sand underneath the paper model, this method was not precise, but it seemed to hold the shape of the model well enough. I used a very coarse aggregate to fill the model, to make sure that the concrete slurry would filter all the way to the bottom. The size of the aggregate was roughly 10mm. For the slurry I used 0,75 part of water for 1 part of cement, in total 7 kg of cement.
I think that the paper was to thin for the size of the model. It was to difficult to shape an area of 50*70 cm of sand underneath a model. The edges of the model was to thin, so it bended, also because the aggregate was so large that it didn’t shape the model from the inside. For the recipe for the slurry I think that I could have used less water since the aggregate was larger than in the previous assignment.
The aim was to create a fine concrete texture, looking like skin.
First the fine aggregate was poured into a frame. A layer of crinkled paper was put on top, and then the cast was filled with the coarse aggregate and filled up with the mix of cement and water.
unfortunately the concrete didn´t went all through the aggregate, so only parts of it came out with the skin-texture.
Probabely the mix was not liquid enough, or not shaked enough so it could reach the bottom of the course aggregate.
Material : Cardstock paper
So to make my paper formwork, I found some geometric shape patterns online and used a thicker paper to make the forms with tape holding everything together. Because I did my assignment a little later than everyone else, I was able to read about other peoples experiences with the slurry mixture and adjust the amount of water I used so that it was more liquidy.
However, although the mixture was pretty thin, it clearly did not reach all the way through aggregate. The concrete only reached about halfway through on each of them. I’m thinking that it was because the aggregate I used was too small.
we decided to use paper folding as a technique to cast concrete for this assignment. we made 2 ‘eggs’: one of them is purely folded, but by forming it to an ‘egg’, some of the foldings are hidden inside the form, which might cause problems for the demoulding process if it gets stuck in the concrete. so we made another one, which is just held together by tape so it does not cause any marks on the inside. furthermore they had 2 different materials: one with a glossy surface, the other one is normal thick paper.
we also had the problem, that there was not enough >5mm gravel left, so we filled one ‘egg’ with normal concrete.
the gravel with glossy paper ‘egg’ turned out quite interesting, the concrete did not get completely down because the gravel was not big enough, but it created 4 columns on the top. the normal concrete with paper ‘egg’ was also fine.
We made two separate moulds. One origami with sharp edges and one with rounded and doubled curvature. Both were made with thick paper.
When we mixed the cement we noticed that it was way too thick to get in between the larger aggregate. Hence, we added more than the doubled amount of water. With 2 kg cement and 1,2 kg water we agreed that the mixture was a flowable enough and could sink through the coarser aggregate. We still had to carefully mix the aggregate with the slurry inside the paper models, and we also shook the whole container as much as we could, so that the paper models would not be deformed.
The resulting models shows that the slurry still didn’t fill the models enough. The origami model lost its lower part, however the edges came out as sharp as the paper model. The larger model came out somewhat deformed. Part of the model lacked cement altogether. We expected that the aperture would still hold, but the finer aggregate in this part filled with cement anyhow, perhaps the paper broke somewhere in the middle.