Skip to main content


Showing posts from May 12, 2013

Proprietary Problems

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 shape of t…

On constructing solo

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 outsi…


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 randomness of 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 registered as an a…


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 overlap of the bricks (…

Gap Filling 101

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 rice.