How to measure tape for engineers
Introduction
The measuring tape is a working instrument used in construction and craftsmanship to measure lengths without the appreciation of a laboratory vernier. The measuring tape may have one or two scales of length measures according to the market where the measuring tape is used. The imperial and metric scale is the two most used measure scales. The measuring tape has length range from 3m (10ft) to 30 m (100ft). The process of using the measuring tape has the following steps: catching the hooked end on one side of the object or space, stretching the tape across the object or space, locking the tape and taking the measurements.
Discussion
Catching the hooked end on one side of the object or space
The hooked end is the part of the measuring tape that has the "zero" length dimension in the measurement. The process consists in catch the hooked end of the measuring tape to the length "zero" of the measurement. The best way to make this process is to use an edge and fixed location to avoid the movement of the measuring tape at the beginning of the measurement. There are magnetically hooked ends that facilitate the fixation of the measuring tape on structures or metallic components. If there are no edges or magnetic borders, the user may use a board or other solid to fix the measuring tape on one side of the measure. When the measures are higher than 1,5m; a second person may be required to support one side of the measuring tape. The next step is to stretch the tape across the object or space.
Stretching the tape across the object or space
The tape is the main component of the measuring tape. As previously stated, the length may be from 3m to 30m, depending on the use of the measuring tape. The stretching process consists in the elimination of the sinusoidal form of the measuring tape due to the gravity force over the tape. The stretching process is possible thanks to the spring system that the measuring tape has in its interior. The elimination of the sinusoidal form will give to the user a better measure. Any variations in the surface may affect the stretching of the measuring tape and as a consequence the accuracy of the measurement. The next step is to lock the measuring tape.
Locking the measuring tape
The lock tape is a component inside the housing of the measuring tape that allows the user to fix the measuring tape to a specific measurement to facilitate the reading of the measure. The necessity of this step is to avoid a continuous stretching of the measuring tape affecting the measuring process and the reading of the measurement. There are different ways to lock the measuring tape; the most commercial way is a contact brake that pushes the tape over the housing giving a resistance force over the tape avoiding the movement caused by the spring. The brake may work by one touch or my continuous push of the user while he takes the measurement. The next step is to take the measure.
Taking the measure.
The measure is the value in meters or inches that the user could take using a measurement instrument. The process of taking the measure or reading is the final step, and that will give the final result of the process. The reading starts by with the big number of the scale and then the user adds the equivalent value of the division scale (Figure 1)
In Figure 1, the first value to consider is 33 in the metric scale that is 33 cm. Between each centimeter, there are ten divisions with a value of 0,1cm or 1mm per division. In the example, there are two divisions between the 33 and the measured item that is 0.2cm or 2mm. The measured value in the example of Figure 1 is 33.2 cm
Figure 1
Conclusion
The measuring tape is a working instrument used in construction and craftsmanship to measure lengths without the appreciation of a laboratory vernier. Using a measuring tape is the process to execute a length measurement with a lower appreciation than a laboratory vernier, but with great utility in the construction and craftsmanship. The use of the measuring tape requires several steps to have a correct measurement. The process involves four steps: the first step is catching the hooked end on one side of the object or space, allowing the instrument to fix the "zero" measure." The second step is stretching the tape across the object or space to reduce errors in the measurement, especially a higher measurement than the real value. The third step is locking the measuring tape to fix it and to facilitate the reading of the value. The last step is taking the measurement according to the scale and the units of the measuring tape and the requirement of the user.
