Geometric errors can have a high impact on the total machine accuracy. Therefore it’s important to carry out these measurements regularly, and one of them is squareness. David Gudmunds at Gudmunds Machine Service in Sweden works daily with checking the geometry of machinery. I decided to ask him about how to carry out squareness measurement in the best possible way.
Hi David! First of all, why is geometric measurement so important?
Measuring the geometry of machinery is important in order to meet the quality requirements of the products and minimise wear on machinery. Squareness error between the axes of a machine tool may result in crooked movement or uneven surfaces. This causes distortion and reduces the lifetime of the machinery. Correct machine geometry is the basis for being able to produce parts that remain within the tolerances. The smaller the tolerances, the higher the geometric requirements, leading to demands for a greater measuring accuracy. Making sure the machine is correctly aligned will increase the lifetime of the machine and its components.
What about squareness measurement specifically?
If one of the machine feet doesn’t sit flat on the base it will cause distortion and stress on the machine’s frame, creating misalignment problems, and possibly severe machine damage. Machine vibration levels may increase and in some cases there will be a measurable rocking of the machine. It’s therefore always important to perform straightness measurement before carrying out squareness measurement. If the machine itself isn’t squared properly, the parts being produced wont’ be square either – and if not corrected, this will most likely lead to premature bearing and ball screw failure.
Tell me about your daily work. What does it involve?
I work partly with preventive maintenance, usually I recommend a baseline reading of alignment for all service work and regular checks and adjustment as part of any ongoing preventive maintenance program. Many times I assist customers if an incident occurs and they need their machines repaired or when it’s time for calibration. Recalibration, including a review of machine alignment, is also important following any machine repair.
You carry out work with the use of laser alignment systems. How does that work for you?
It works perfectly fine. Compared to conventional methods, such as dial gauges together with stones and shafts, work can be carried out much more quickly with the use of a laser measurement system. Traditionally, you would have to visually check one plane at a time and use different tools for different sized machines. You would also have to write down all the measurements manually and also take the temperature of the stone into consideration since heating and cooling contribute to thermal expansion. This is all very time consuming and difficult.
To use the laser equipment it´s easy you can read the straightness values in two planes at the same time Measuring squareness on machinery using a laser alignment system is much faster and easier. The laser system provides you with full documentation with direct generation of PDF reports and database programs for PC.
How to measure squareness fast and easy
Using a laser alignment system will allow you to precisely measure so that true squareness can quickly, easily and accurately be determined for optimal manufacturing efficiency. There are various laser alignment systems available on the market. For fast and easy measurements we recommend our complete Easy-Laser® system E940 for measurement and alignment of machine tools or our Easy-Laser® system E920 for other types of basic geometric measurement.
This is how you carry out the measurement: (You need first to check the straightness)
- First record two measurement values on a single object to create a reference for the angle.
- Then use the built-in prism in laser transmitter D22, which deflects the laser beam 90°, and record two new measurement values on the second object. The measurement values are converted into an angular value, showing any deviation from 90° in the second object.
- When a very high level of accuracy is required when measuring squareness, where we want to exceed the accuracy of the laser transmitter (D22 according to technical specification 0.01 mm/m), we use a method where the laser transmitter is indexed 180°. The method is suitable for the measurement of squareness in relation to two points on a reference plane, or for measuring plumb where we use the vials on the transmitter as reference.
If you like this article, please let us know by leaving a comment in the field below! If you have any questions about geometric measurement or squareness measurement, don’t hesitate to give us a ring! Also read Get it straight with Easy-Laser® and Parallelism – a key factor for top product quality.