You can cut aluminum with a sabre saw, but it requires a certain technique and the right sort of equipment. Because aluminum is a particularly soft metal, you can only cut it with certain types of blades. For example, you can not use a carbide blade for this project because it will get very hot when operating at high speeds and it can get clogged. Using the wrong type of blade will not only destroy the blade completely and make the job take far longer, but it can also be dangerous, causing red hot bits of aluminum sheeting to shoot around. You can use a sabre saw to get the job done correctly without it taking much time or effort. Anyone with a basic set of DIY skills should be able to handle this project without a problem.
Step 1 - Marking the Cutting Lines
Use a special marker pen that does not easily rub off from an aluminum surface. Any permanent marker pen should do. Mark on the underside of the aluminum sheeting where you want to cut it. Use a long scaled ruler to make sure that the measurements are as exact as possible. Ideally, the ruler should be longer than the longest line you need to draw. You will get normally a much higher degree of accuracy this way. It also makes things a lot easier.
Before making any markings, it is a good idea to draw out a plan on paper and get as accurate an idea as possible of the required measurements. Aluminum is quite expensive, so be sure to double check your measurements to make sure that everything is correct before cutting.
Step 2 - Cutting the Aluminum
You can use the sabre saw to cut along the lines you have marked on the sheeting. Make sure that you have an appropriate surface to work on, one that is level and secure. You may want to consider using eye protection before starting.
On a raised surface, have the aluminum sheeting hanging over the edge. Have the line you are to cut against the edge of the work surface, and then cut it with the sabre saw. The saw should effortlessly cut through the aluminum so long as you maintain a steady grip on it and have an adequate work surface.
When you first cut the aluminum sheeting, you will likely have a rough edge on it. These edges can be razor sharp and should be handled with care until they have been filed down.
Step 3 - Finishing Touches
When you have cut the aluminum as required, you will need to use a coarse file to smoothen the edges. Take great care in doing this as the edges can easily cause cuts. Use the file to get right of any burrs, twists or jagged ends in the edge of the sheeting. When you have done this, the sheeting will be ready to use.