Concrete Base:
"Ready-mix" concrete may be used, or the concrete is to be mixed on the site. If the concrete is to be mixed at the site, a recommended mix is 1 part portland cement, 2 parts clean dry sand and 2 1/2 parts gravel or crushed stone, by volume.
First, dig the footings and construct the forms for the base. If the holes are dug accurately to the required depth of 24 inches, forms may not be necessary, for the earth will provide its own form. If the surface of the base is to be above the existing ground level, it will be necessary to build a wood form in the shape of the base. In either case, the surface of the concrete should be finished flat and level.
The concrete may be mixed in a wheelbarrow with a garden hoe. Ingredients should be thoroughly blended, as directed above, before adding water. No more than six gallons of water per bag of cement should be used. In estimating, it can be assumed that the yield of the concrete will be approximately equal to the quantity of gravel used. The concrete should begin to set within one half hour and should be covered with burlap or plastic for the first 48 hours.
Bricklaying:
Bricklaying tools include a hammer, mason's string, a few 10d nails, a trowel, a spirit level, a hand level, a piece of carpenters chalk and a broad-bladed cold chisel. The chisel, called a brick set, is used for cutting brick. A tap on the chisel with the hammer will score the brick along the line of the cut. This is done on two surfaces of the brick. Then, pointing the chisel inward, strike a sharp blow with the hammer, a clean break should result.
Brick should not be laid bone dry. They should be damp, but not wet. A thorough spraying with a hose 15 minutes before using will usually suffice.
Before using any mortar, use 1 part Portland cement, 1/4 part hydrated lime, and 3 parts fine, clean sand by volume. Add enough water to get the consistency of soft mud. It's about right when it slides from the shovel easily, but does not run. Mix small batches - by the shovelful, not the bagful (i.e. 1 shovelful of cement, 1/4 shovelful lime, 3 shovels full sand). No more mortar should be mixed than can be used up in 2 hours. Should the mortar lose is plasticity before being used, temper it by remixing with a little fresh water.
Build the corners first, going three or four courses high, then filling in the wall from corner to corner. Be sure to lay the bottom course on mortar to bond it to the slab. Frequent use of a hand level will help keep the wall plumb and the courses level. Make all mortar joints even at 1/2 inch.
Excess mortar can be clipped off every 2 or 3 courses with the trowel. Tooling is done at the same time to seal the joints. For tooling, a short length of pipe, slightly larger in diameter than the thickness of the joints, can be used, working first vertically then horizontally to achieve a concave joint.
- Note: A secret of good brickwork is not to move a brick once it is in place, consequently, care in placing the brick in mortar pays off.
Spread a bed (horizontal) joint first to the proper thickness for not more than three bricks at a time. Roughen the surface of the mortar by making a shallow furrow with the point of the trowel. The head (vertical) joint is applied by spreading one end of the brick with mortar. Make sure that all joints are completely filled with mortar - to insure a watertight barbecue.
Courtesy of the Brick Institute of America
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