technē and poiēsis

I was playing around with the clay, trying to think of what to do  for the sleeping surface part of the shelter. I thought I would try a different method of forming tiles. Roman tile-makers formed roof tiles by slapping clay over their thighs- thighs had the proper length and taper, I suppose. In the past, I have used a rolling method, where a sheet of clay is rolled out between a frame that has the proper thickness. I decided to try making catenary curve tiles. If the frame was placed on some sort of fabric or mesh that could then be hung, the tile would take a catenary shape- then it would be in pure compression when flipped over.   It worked quite well. I was afraid the clay would crack, but after the first day of drying it is fine. I think if I continue testing I will use a thinner sheet of clay and try to get more control over the height of the mesh. I can also perhaps suspend from more than 4 points to make different curves.  I also like the fact that the ...

On my mini-vacation I decided to go to Brighton to see a bit of the ocean. I had one day of sunshine and one day of constant rain, so I wandered the beach and then when it was raining visited some museums. I had the chance to see the chalk and flint geology of the coast and then find out about it. I found out that flint is almost pure silica and is believed to be formed from the decomposition and recrystallization of a certain kind of sea sponge. The flint in Brighton is found in its familiar irregular nodules but also in the form of pebbles that have lost their white and translucent colours from constant washing in the sea. There is also chalk, in which large quantities of flint stones are embedded. Chalk is a very soft rock. Even just handling pieces left a milky white residue on my hands. The flints appear in the clay soil at Grymsdyke Farm because the chalk that once surrounded them was worn away by weathering, leaving the very fine particles that make clay. The harder flint rem...

It has been slow going, and I am just beginning to get good at this mortaring business, but for now, the roof is done! I am going to take a break for a couple of days before continuing to work on the intersections.

I must be able to convert sunlight into energy, because when it is sunny out I feel like I can work the whole day and still want to go for a walk in the evening. There's probably a limit, though, because it is also hard to work when the sun is hot and fierce. But here, in the 5 degree weather, it is a joy. Something similar happens when I look at the shelter. In the sunlight, when there are sharp shadows and the brick glows orange, I am proud of it. I can believe that it is expressive and possibly beautiful. When it is grey, though, especially when I am cold and tired and working close to the joints, I can't help but think it dull and awkward. A moment of sun...

I cut the formwork for the roof on the CNC (with help) last summer before I left. I used two sheets of OSB that were lying around. Since I was eager to have as little waste as possible and since there were only those two sheets, I made each "rafter" slightly shorter than necessary, counting on the ability of whatever binding agent I would be using to build up the rest. Well, as I've written previously, I couldn't find the ideal binding agent. I have realized that it is so much easier to just add extensions to the formwork rather than get frustrated trying to make the bricks stick immediately. This formwork has turned in to a bit of a bricolage but it is doing its job.

Why do I make things more complicated for myself? If I started this project again I would do a lot of things differently. I am figuring everything out as I do it.  I was having trouble getting the bricks to sit properly on the formwork when it is almost vertical. They keep sliding down or twisting. So I decided what I needed was something to start the first brick of the row, so I could build off of it. What I came up with was a kind of cradle for the brick. It can balance on the wall and I can adjust the angle as necessary. Then I realized that I didn't need any of that. Some binder clips work just as well. I can attach them to the existing formwork and support each brick that needs it, rather than just the bottom one.

Besides using clay as a plug to stop mortar dropping, I am also experimenting with molding some bricks on site. It is a way of assuring a snug fit between the roof and the wall. I can't decide if I think it is a cop-out or if I am just exploiting the versatility of the material. The clay shrinking is again an advantage- the bricks are stuck for a day or so, and then they loosen themselves. Eventually, when they are dry, I will fire them. I am wondering as well whether there are other ways of finishing their surfaces, perhaps to try to get crisper angles.

A rare sunny evening... So, the resin is a pain. I have vowed never again to work with resin. I get stressed because if I don't use it fast enough it hardens in the nozzle. I thought I could use it to bridge the gap between the bricks, but it often won't build up enough to reach the two surfaces and it gets messy really quickly. Plus it smells very toxic.  It is useful for immobilizing the brick and it is very strong, so I will continue with it for now. But  I have decided to only put resin where the bricks are close enough, and then plug the hole from underneath with clay. Clay is actually an excellent plugging substance. It is sticky and grippy when it is moist, so I can fill the mortar from the top without any falling out. Then, when the clay dries, it shrinks and pulls away from the brick, so I can collect it for soaking and reuse.  The underside of the formwork. It doesn't look like much, but the clay has been essential for me.

I'm learning how to accurately drop mortar into the joints. I often miss and then the cement makes stains on the bricks. I also make a lot of crumbs and I have to resist the urge to brush them until they are dry, because otherwise they also stain the bricks. The best way, I've found, is to be patient- only take a bit of mortar at a time, and prepare the little bit on the big trowel before using the little trowel to flick it off. I have to make sure the joints are fully filled but I also don't want it to get super messy. I still have a lot to improve...

In this post I wrote about my gap filling tests. I decided to go with the resin/mortar combination. I ordered some resin from Screw-fix because it is relatively cheap and because I had spoken with a structural engineer last summer and he had recommended it. The problem is, it comes in a proprietary tube that doesn't fit in a regular caulking gun. I had already decided that I would make a custom tool to help me apply it to the bricks, but I never imagined the tool would require so much effort to make. Here's what I've come up with. It is based on the same principle as the clay extruder I made last fall.  The first problem was the extreme amount of pressure that is applied to the pieces. Initially, the notches on the vertical post were pieces that I attached with screws, but the force of the bar was ripping them out. So instead, I notched out the post itself. As well, the plate where the tube rests had to be re-anchored with extra support.  The second problem was the ...

It's hard being the only person working on this project. Physically, it means a lot of redundant work- going up and down the ladder, going back and forth from the workshop, going in circles trying to find that darn jigsaw that I had a moment ago...Mentally, it's stressful, because there no one else to blame when things aren't going right. I'm only half joking. I am accountable to myself, fully and entirely. I feel like I push myself farther when I am alone, for that reason, but I also feel the weight of every action in my mind. At a recent thesis defense where the defendant presented a beautiful timber framed "Oneiric Hut", one of the panelist's comments was that he was guilty of "the sin of pride": not asking for help, wanting it to be his alone. But even he had help- he had his wife as a partner throughout the building process. That is the best kind of help, a partnership where everyone is equally committed to the project. To just ask for out...

It is impossible to understand the clay here without knowing about flint. I am surprised I haven't posted about it before. Actually, the weather has been dismal for the past few days, and I am just waiting to be able to start construction again. The flint comes in rounded nodules of very bizarre shapes. They are whitish on the outside, although it is very rare to find one that hasn't been chipped. Inside, they are translucent purple. Many of the houses around here are made of brick with an infill of 'knapped flint'- they cover the facade with a layer of render and then embed the flint, cut side out (the knapped side). The workshop and cottage of Grymsdyke Farm are made in this way. They are older than the main house. On one of my walks I saw two houses side by side, both of which were red brick and flint. One was built in 1893, the other in 2001. They looked so similar it was uncanny. Normally new houses have something that betrays their newness. But the...

I thought I would share another project that is going on at the farm right now. The kitchen is being renovated and as part of that project, Ed and Kate are slip casting custom tiles for a backsplash. Slip casting is an interesting process. It takes advantage of the viscosity and adherence of a liquid clay mixture. Liquid slip is poured into a mold so that it coats all sides, and then the excess is poured out. The molds they've made are in two parts and are cast from a special hydrophilic plaster that absorbs the moisture from the clay. Below you can see the mold, with the hole for pouring the slip. The originals were milled from a high-density model foam on the CNC machine. The motion of the tool bit is what creates the corrugations on the surface. One thing Ed said was that if they turned up the speed of the bit, it produced a wobble that was quite human in its imperfection. It's an interesting concept to consider- the fact that the actions of the machine are register...

Joining bricks horizontally is difficult. Well, actually, cleanly joining bricks horizontally is difficult. Is it a tool problem? Is it a material problem? Is it simply a silly thing to attempt? I know from experience that mortar falls off the brick when it is turned sideways. Unless the mortar is really wet, and then it gets sloppy. So, I thought of using a two-step process: first, join the bricks with something really sticky, like resin. Then, pack mortar in from the top, using the resin as a base. The trial I made, though, is still very messy on the bottom. The underside of the test piece. The resin is uneven and the mortar is showing through in some places. Here you can see the resin on the bottom and the mortar on top. I decided to try using plaster as the adhesive. I thought I could trowel it on accurately, but it was still really messy. Then I thought that if I had a surface against which I could wipe the trowel, it might produce a sharper edge. I modelled the o...

Bricks and mortar are a natural pair. Interesting fact: the phrase is an idiom with two meanings . The first meaning is simple or basic: a "The online course covered only the bricks-and-mortar of the subject". The second meaning describes a business that has a physical presence instead of only an online one. "The startup began online, but shifted towards a brick-and-mortar presence in major cities". Mortar, however, is only one option for joining bricks. Mortar, grout, and caulking are all words that can be taken to mean a plastic substance that fills a gap between two solid objects. As well, there is a spectrum of resins and adhesives that can also be used to bond masonry. Here is a basic overview of some options. Lime Mortar: This kind of mortar has been used for millennia. Its basic composition is lime putty and sand, although many additives such as plant fibres and clay have been used to improve its strength and flexibility. The Chinese even added sticky...

Last summer I believed that the clay and flint of the soil were best friends and could only be separated with great effort. And it is true, as long as the clay is damp or wet. Now, I realize that there is a way to easily detach the two materials. The clay just has to be dry, and then any blow with a hammer will split the clod exactly where the rocks are. There is still a good deal of work involved, because the rocks have to be picked out by hand, but it is work that can be done whenever I have a few minutes to spare. Instead of having to invest a few hours at a time to process the wet clay, I can pick over a couple handfuls when I feel like it. Luckily the flint pieces are white, because the clods of dry clay and the stones are about the same hardness when touched. I can tell the difference by the colour and sometimes the geometry- the flint pieces have more thin edges.

A good friend of mine gave me a mixing trowel and a jointing trowel for my birthday last year, and I was eager to try them out. I put together some of the scaffolding for the roof to do some tests.  It is interesting to find out how techniques are embedded in the shape of a tool. For instance, the thin jointing trowel has a fixed width of 1/8", written on the blade. I suppose masons would have a whole collection of different widths for different projects. It is not so intuitive to use on the variable-width joints I am dealing with. As well, it has a long, straight blade that does not accommodate the curves. I ended up using only the tip for most of the joints. Still, I found that it was useful because it is long and thin. I can use it to pack the mortar into the gaps.