Sydney Bricks: A brief history.

Bricks Manufactured in Sydney Australia

Up until the 1970s, the vast majority of Sydney's bricks were manufactured within the inner west, predominantly the Marrickville and Newtown area. The inner west region was selected thanks to it's abundance of clay in the form of Wianamatta Shale by Australia's first colonial settlers. During the industrial revolution when machinery increased the mass production of bricks, tiles and other earthenware, alternate locations of clay deposits were needed to replace an almost depleted inner west now sporting a large empty quarry only 4 kilometers from the cities central business district. The vast clay pits which had been excavated for clay were repurposed as waste tips with prominent structures remaining on site to this day, including the brick works located in St Peters in what is known today as Sydney Park, which was remediated by layering soil and rubble on top of the refuse to create a large park and waterlands environment which is open to the public. 

Real Sydney Bricks - retro
Sydney Bricks today now second hand

The Mortar Disorder

ˈmɔːtə/
noun
noun: mortar

A mixture of lime with cement, sand, and water, used in building to bond bricks or stones.

NOTE: Rather than replicate the same content available on several thousand pages across the internet discussing the correct ratios of ingredients and proper application technique, this article is an attempt to address the areas of research which are integral to the end outcome of any masonry project. 

The relationship between bricks and mortar is not dissimilar to that of the relationship between shoes and shoelaces or cameras and film, given that each without the other is practically useless or to quote Aristotle, the whole is greater than the sum of its parts.
Historically speaking, mortar was simply the uncured format of the construction medium being used ie, clay for clay bricks and lime and gypsum being utilised for setting stones and slate.
Much like the process of laying bricks, the composition of modern mortars differ only slightly to that of long past eras with the fundamentals qualities being universal, the ingredient list seldom changes without technological advancement or designs specifically formulated for specialty applications. 
So, sounds simple right, people have been affixing one brick to another for millennia and the material that binds them is practically the same that built the colosseum , how could you possibly go wrong? Well, there are actually plenty of ways that you can make a complete and utter mess of your little weekend DIY project. Take for example your local Bunnings, the obvious choice for retail levels of building supplies, a shop specifically targeted at the do it yourself market, check out the mortar isle and you will soon be met by a selection of over 60 different products with prices ranging from loose change to entire paycheques. 

Selecting the right product for the right job is one of the most important steps in the entire process of restoring, modifying or laying bricks, therefor it is important have a clear understanding of what exactly it is that you are trying to achieve. Australia's older brick structures (pre 1940) generally were constructed with a soft pure lime mortar and new developments tend to use a much harder cement compound with variations and mixtures of the two types appearing sporadically throughout the interim. Basically, some mortars are traditional "which may be important if you are wishing to restore a structure to period correct qualities" some are easier to work with and some will yield better results in certain environments. 
Examine the situation, determine what nature of mortar is keeping your existing bricks together, scratch it with a sharp metallic object, does it scratch and leave a mark, if yes - chance are that you've got a soft lime mortar compound (traditional) if more resilient, crumbly and containing reflective silica you may have a modern cement mortar, not sure from questionable results, why not examine other structures erected in the area from a similar period and those which are newer, it may give you contrast and perspective. If still no clear conclusions, you may want to look at having an expert examine the chemical composition of the mortar for accurate analysis. 

And that's practically it, now that you have an understanding of what you're dealing with and what you wish to achieve, you can now read the articles necessary to do so without getting mislead by conflicting ideas and instructions. Below are a few handy resources on using various forms of render>

How to mix all kinds of Mortar
Restorative and conservation works
U
ltra modern techniques and materials

Building a Brick Walkway

If you thought brick walks were just for the rich and famous, it may be time to re-evaluate your status in life. A modest brick paving project is a great way to add character to your home—without breaking the bank or calling in a landscape professional. The work is not particularly complicated, and careful preparation will ensure a job that is beautiful and long lasting. In fact, brick walks have been known to last for more than a hundred years.

Planning


First, make a scale drawing of your walkway to help calculate material quantities. Then, decide upon a brick pattern. The simplest choice is the running-bond pattern that we used. Other popular patterns are herringbone and basket weave (see drawings). The patterns can be aligned with the direction of your walk, or at an angle. Keep in mind, though, that a complicated pattern or angled alignment will result in more waste.
Bricks used for walks, patios and driveways are called pavers and they’re not the same as those used for wall or fireplace construction. Ordinary brick is much too porous and soft for paving applications, and would quickly crack and disintegrate if used for a walk. A standard paver measures 3 3⁄4 x 7 1⁄2 in., and is about 2 1⁄8 in. thick. Calculate the area of your walkway and allow five bricks per square foot. For a running bond, add 10 percent for cutting and defects. If your walk has a curved or angled shape, or if you choose a more involved pattern, allow extra bricks for cutting.

Preparation 

Before beginning the walk, inspect the site and check the slope of the ground. Use a straight 2 x 4 and level to determine the slope. Ideally, the walk should be at the same height as the surrounding ground. In some cases, adjusting the height and pitch of the walk may be necessary. It’s important that the walk have a slight slope to allow water to run off the surface. The pitch should run away from any adjacent building, and it’s acceptable for the walk to slope slightly to one side to drain water. The required slope is 1⁄4 in. per every 4 ft. of run, so you won’t notice it when using the walk.
Determine the outline of the walkway excavation. Your hole should be at least 6 in. wider than the finished walk on each edge. Lay long 2 x 4s on the grass to indicate the edges. If the walk is to be curved, you can use a garden hose or heavy rope to mark the outline. Spread a line of ground limestone just inside the border to mark the grass. Then, remove the 2 x 4s, use a spade to cut the grass along your layout lines and remove the sod.
Now drive wooden stakes into the surrounding grass. Keep the stakes about 12 in. away from the edge of the hole, and space them about 3 ft. apart along the length of the walk on both edges. Stretch mason’s line between pairs of stakes across the walkway area. The lines will serve as guides for gauging the depth of the hole and the stone base. Adjust the height of the string so it’s at a uniform distance above the adjacent ground surface. The height of the string is arbitrary, but it should be high enough above the hole so it won’t interfere with your work.
Continue excavating the site of the walk. Use the shovel to cut the sides of the hole vertically so the gravel base will be at its full depth right to the edge of the hole. Check the depth of the hole by measuring up to the string guides. The bottom of the hole should be approximately 7 1⁄2 in. below the surface of the ground. Try for a reasonably flat-bottomed hole. If you remove any large stones, simply fill the recesses with gravel.

Prepare The Bed

Use a wheelbarrow to bring the gravel to the excavation. Spread the gravel to a minimum depth of 4 in. with a garden rake. Check the height of the gravel against the guide strings. When the gravel is at the proper height, remove the strings to provide unobstructed access to the site. This is the time to set the slope of your walk. Adjust the pitch of the base by adding more gravel where required. Use a length of 2 x 4 and your level to check the slope.
Next, use the plate compactor to pack the gravel base. Slowly move the machine over the surface several times. Proper compacting of the base will prevent the walk from settling later.
Temporarily place a row of bricks at each end of the walk to act as guides in positioning the edge restraints. This technique minimises the amount of cutting required. If you’re using the running-bond pattern, it’s especially important to avoid having partial bricks at the edges.
Place the edging against the bricks and drive the landscape spikes to lock it in place. Space the spikes about 3 ft. apart along the edging. Where necessary, cut the edging to length with a hacksaw. If your walk has a curved profile, simply cut the webbing on the outside of the edging so it can be bent to the required shape.
Spread a 1-in.-deep layer of sand over the gravel base (Fig. Use a 2 x 4 to screed the sand to a smooth surface. If you cut a 1 3⁄4-in.-deep notch at each end of the 2 x 4, you can rest the notches on the edge restraints while you pull the 2 x 4 across the sand.

Laying Bricks

Begin laying the bricks at one end of the walk. For a running-bond pattern, stagger the bricks by half their length, leaving the spaces at the end to be filled later. Once you have about 2 ft. of the walkway laid out, you can kneel on the bricks to work. Take care to lay each brick so its edges tightly abut the adjacent bricks. Once all the full bricks are laid, use the saw to cut bricks to fill the spaces in the walk. Fill the reservoir in the saw base with water. The water is circulated to cool the blade and keep dust to a minimum.
After all the bricks are in place, go over the walk several times with the plate compactor to settle the bricks into the sand base. This procedure locks the bricks in place to help keep them from shifting when the walk is exposed to
severe weather or heavy use.
Use a broom to brush sand over the surface to fill the spaces between the bricks. Go over the walk several times to ensure a thorough job. Sweep up the excess and lightly hose down the walk to remove any dust. After the walk has been in service for a couple of weeks, repeat the sand application.
Backfill the walk excavation with topsoil, covering the exposed webbing of the edge restraint. Tamp the soil down to compact it, then plant grass to fill in the lawn up to the edge of the walk. The roots of the grass will grow through the holes in the edge restraint to further lock it in place. You also can plant flowers, small shrubs or ground cover to border the walk.

Now enjoy your new brick walkway, and the beautiful look it gives your home for years to come.