I have about 16 school chalkboards 4 ft. by 8 ft. made of sheet metal laminated to 1/2" K3 board with a green paint for chalk. Want to use them to line my new workshop on the inside. Looking for a method to cut the chalkboards to length and width cheaply as possible. Would like to made one cut metal and K3 AT THE SAME TIME. thank you.
Cutting sheet metal on K3 board
cutting
Related Solutions
My experience says to use the rotary tool, but I have always used metal boxes with plaster rings. I have no experience cutting drywall over plastic boxes. I do have three pointers for cutting with a rotary tool:
- Put as little pressure on the box from the drywall as possible. The more pressure against the drywall, the more likely that you'll get tearout near the edge of the box.
- Leave any NM cable sheathed and set the depth of the cut to the minimum possible to reach the box plus a half an inch (keeping in mind that the drywall will be at an angle to the box).
- Always take a few seconds to visualize your cut. Have a good idea of where your corners are so you can anticipate direction changes. Do a sanity check and make right sure you know which way counterclockwise is. Start out going clockwise, and you'll spend a lot of time repairing drywall.
If you still don't want to use the rotary tool, there is another option. There are tools that attach to plastic electric boxes. You put them on and then position the drywall where it will be installed. Press the drywall against the tool, and it will place small perforations at the outside corners of the box. Connect the dots and cut. The image below is of one of mine, but I haven't had the chance to use it yet.
If you try to do this with a circular saw, your "straight line" will look straight only to Salvatore Dali. A heavy duty street cutter is required.
Of course, what objective there could be in cutting a driveway we can only guess at.
Best Answer
A carbide tooth skill saw blade will cut the combination, I use a 70 tooth if i need a really clean cut on thicker metal, but a "finish" blade will work, make sure to wear safety goggles , gloves and a long sleve shirt or coat at some of the chips get thrown.