String Lines and Plumb Bobs for Roll Cage and Race Car Fabrication
Old Tools New Projects, Even the ancient Egyptians used these tools
The string line and plumb bob tools have been in use for thousands of years. Earliest records show them being used to make the pyramids in Egypt. And it has lasted the test of time for good reason. It’s simple and effective. We use the string line tool on our builds in many different ways. The only major changes to our tools sense ancient Egyptian times is the use of modern materials and magnets.
How String Builds a Straight Race Car Chassis and Strong Roll Cage
The basic principle is simple. When you pull a string tight against two points it makes a near perfect line. Not exactly perfect but very very close. That’s good for us. Sometimes we need something straight as a reference. A good example is when we need to do a wheel alignment on our race car. Modern laser alignment systems will do this job faster and better but for us DIY folks, the string is the best way to do that task. But the string line can do so many more things. With the use of other tools it can make angle measurements. For example you can use the magnets and the string to measure the angle any tube needs to be in the frame or roll cage. The string is ran from one point to another and held in place with magnets. Then using an angle finder, you can measure the strings angle as it sits. That angle is the angle the tube must be cut to in order to fit correctly. If you have a tube notching machine you can set the angle of that machine using this method. There’s more! Adding a bubble level to the string allows us to see if things are slanted. If you need tubes to be the same on the left and right sides of the car or from front to back, the string line and bubble level can tell you if one tube is higher or lower than the other. Simply run the string from one tube to the other and attach the bubble level. It can also be used for making plains. When attaching tabs to a frame to support a sheet metal panel, it’s important to make the tabs all on the same plane. Run the string from tube to tube and make it nice and tight. Then with our universal tab positioner set the tab to just barely match the string. That ensures that all the tabs are at the same height, same angle, and fairly precise. The more you use the string line tool the more you will find it can do. The plumb bob is used for vertical alignment. Any tube that must be up and down or centered over something on the bottom, use this tool to do that.
