Today's "How to" article courtesy of English-blog contributor Adam Mc.:
The Art of Concrete
Ever since the age of twelve I've been working for my dad pouring cement. I've been learning about it and hearing about it since before I can remember. My dad taught me the trade and his dad taught him. Most people would think that it's a simple process. You pour the cement, you smooth it out and you're done right? However, just like any other job it's not as easy as it appears at first glance. In fact the job is so complicated that even after seven grueling summers of pouring cement, for less than reasonable wages, I'm still learning something new each time. And even though the pay is low I'm gaining experience that will last me the rest of my life. So now I'll try to sum up in a few paragraphs what has taken me seven years to learn . . .
. . . Before you ever start to pour the cement, you first need to form a job up. Like a body needs bones for structure and support, wet cement needs something solid to give it shape and hold it in place. For this wooden boards, mostly 2"x4", are placed in a pre-measured area and nailed together. Two to three foot long pins are then placed behind the boards about every two feet for additional support. In recent years some contractors have begin to use plastic forms that clip together. Benefits of these forms are that they do not require any nails to be held together, they are more pliable for doing curved edges, and they will last much longer than regular wooden boards. However, most contractors still use wooden boards due to the high cost of the plastic forms.
Once you have the area you wish to pour formed up it's time to order the cement. This is done by placing an order with the concrete supplier. This is a company that specializes in making the concrete from water, limestone, sand, gravel, and of course the cement powder. They may also deal with supplying someone with these individual components if that is what the customer wishes, but mainly they mix these components together to make concrete. Generally, the companies that supply you with the concrete like their orders to be placed at least one day in advance. To do this you must find the cement supplier that is closest to the job where you are working, or the company that that customer wishes you to use, call them and tell them how much concrete you are going to need in yards. A yard is twenty seven cubic feet, so you must take into account how large the area is that you wish to pour and how thick you are going to pour it. Once you have this figured out you place your order and hope that they aren't too busy.
So now you have concrete ordered. You show up at the job at least one hour before the concrete truck, or trucks, are going to show up. You need to get all the tools out that you are going to need in order to properly pour the cement. These tools may vary depending upon how large or what kind of area you are going to pour. The basic tools for putting the cement down and smoothing it out the first time are the lute, the straight edge, and the bull float. The lute resembles a rake but without teeth. This tool is used for raking the cement around after it has been poured from the truck and making it as level as possible. The more level it is the easier it will be to straight edge. The straight edge is a metal board that comes in several different sizes; 2"x4", 2"x6", 2"x8", and 2"x10". The length you use depends on the size of the area being poured. To use a straight edge you must drag it across the cement in a saw like motion. This is the next step in making the cement as smooth as possible. Once this task is completed it's time to use the bull float. The bull float is a flattened metal board that is attached to a metal pole. In order to use the bull float you must first push it out across the cement and then drag it back across to you. When pushing out on the bull float make sure that you twist the handle clockwise so the front end will pick up slightly. Likewise, when pulling it back across, twist the handle counter clockwise so that the back end will pick up slightly. Note that it is ideal to have a different person doing each job so that you can maximize your efficiency.
You're halfway done now. It's time putting the finishing touches on your project. Before you go any further you have to put the first finish on the cement. There are three main tools for this job; the mag, the finish blade and the edger. The mag is simply a flat piece of metal attached to a wooden handle and it is approximately one foot long and three inches wide. This is used to flatten the cement further and bring the cream of the cement up to the top. This makes it easier to smooth the cement out with your next tool the finish blade. The finish blade is similar to the mag but slightly larger and extremely sharp. You have to be very careful with the finish blade since it is razor sharp and very easy to cut yourself with. The finish blade makes your concrete very smooth and you're now ready to put an edge on your concrete. The edger, hence the name, is used to put a rounded edge on your concrete. It's simply a flat piece of metal that is bent on one side to give you a nice round edge on your concrete. To use the edger move the tool back and forth slowly with slightly more pressure on the side opposite of the direction you are going.
Now that your concrete is smooth with a nice round edge on it you have two options. Option one is the more simpler of the two and that is to "broom" finish your concrete. This is done with a large broom attached to the same poles that you used earlier with the bull float. One stroke up and one stroke back should be sufficient, but if not continue until you have a nice, even broom stroke on your concrete. This type of finish is done mainly for sidewalks and driveways. The second option is to give your concrete a "smooth" finish. This type of finish is done mainly for large commercial projects such as warehouses, factories, or large garages. To do this you need a finish machine. A finish machine is a motorized finisher with four blades that are similar to the finish blades you used earlier. Once again, you need to be very careful with these blades since they are razor sharp, not to mention the fact that there are now four of them and they are spinning. You run the finish machine over the concrete until you get a very smooth, almost glassy look to your concrete. Some contractors prefer to use the finish blades that we discussed earlier to achieve this, and surprisingly this method is actually quicker. However it is also requires more work and no matter how good you are it won't be as smooth as it will when it's done with the finishing machine.
Now you have one more step before you can pack it all up and go home. The only thing left to do is to put the sealer on the cement. The sealer is a liquid that is sprayed onto the concrete after it has been finished. The purpose of the sealer is to preserve the concrete so that it will last longer. It also gives the concrete a nicer color and actually makes it smoother.
So now you've finished your concrete job. The whole process will take about six to seven hours from start to finish. It's a long a tiresome job, but once it's done the concrete will last for many years afterwards and you don't have to worry about maintaining it. So clean up your tools, pack up, and head home.
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Comments for Adam's article "The Art of Concrete?" Please leave them below:
Posted by lhobbs at December 2, 2005 04:55 PM
Great information !!! Thank you for sharing some of your experience. It will be very helpful.
Posted by: Chuck at August 30, 2006 12:53 PM
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