Dimensional Inspection – Important Part of CNC Product Quality Control

In recent years, with the establishment of ISO, it has become necessary to maintain forms, and the measurement data of parts contributes to the improvement of this quality. The measuring instruments that make full use of the latest measurement technology and the measurement data created by skilled measurement technicians are highly trusted by many users. “Reduce working hours” and “shorten delivery time” are important issues in manufacturing, and this is no exception in the quality control process. Therefore, CMM is widely used for Dimensional Inspection of CNC processed tools ( 2D drawings, 3D Models, master product or tooling).

In this CMM service, CNC’s coordinate measuring machine is used to measure the dimensions of drawings and 3D models, and the measurement data is submitted through output methods such as inspection tables and model matching. We can handle a wide range of products from small parts to large products, and provide accurate measurement data for various objects in various industries. We have a large number of measuring machines and verification software of various sizes/manufacturers, so that we can provide the best measurement results for the measured object, the evaluation content and the required accuracy.

What is Dimensional Inspection?

In recent years, the development of 3D printers has improved the accuracy of modeling, and CNC modeling products have begun to be used for various purposes. However, in order to use a model product as a fixture or a final part, it needs to be evaluated to ensure quality, and dimensional inspection is one of the important evaluation items in this evaluation.

Dimension Inspection Data

For most inspection equipment, there is a means prepared to directly transmit dimensional data to the dimensional inspection report. The transmission of dimensional inspection data greatly contributes to the prevention of erroneous entry mistakes due to manual input, etc., and also contributes to reducing the human stress of the confirmer when checking the dimensional report.

Dimensional Inspection Methods

There are roughly two types of dimensional measurement methods, including analog dimensional measurement such as calipers and gauges, and three-dimensional measurement using a portal type or articulated arm type.

Compared to conventional analog dimensional measurement, 3D measurement is an excellent one that can be expected to dramatically improve the process.

Here, we will introduce the know-how of new Coordinate Measuring Machines that can be expected to solve your problems from the basic knowledge of Coordinate Measuring Machines.

How To Use CMM To Do Dimensional Inspection?

CMM is suitable for measuring the dimensions and shape of 3D objects. Coordinate Measuring Machine is performed in the three-dimensional direction (X, Y, Z) using a contact-type measuring machine that takes a coordinate point by bringing a spherical stylus (contactor) attached to the tip of the probe into contact with the product. to hold. It is possible to perform advanced dimensional measurements such as geometric tolerance measurement that cannot be measured with calipers with high accuracy.

  • Generally, select a measurement target called an “element” such as a plane on the menu and start measurement.
  • In the case of a contact-type coordinate measuring machine, the tip of the stylus is brought into contact with the object to be measured and a measurement point is taken.
  • The element is measured by measuring the minimum number of measurement points specified for each element.
  • If the number of measurement points is further increased, it is often calculated by the method of least squares.
  • In addition to planes, measurement elements include lines, points, circles, cylinders, cones, and spheres.
  • By calculating the distance and angle between the measured elements, the dimensions and three-dimensional shape are measured.

Advantage of Using CMM for Dimensional Inspection

  • Only use 3D measuring machine for measurement – Using 3D measuring instruments, you can evaluate and measure complex shapes of solids. You can evaluate the free phase, calculate the position of the virtual point, etc.
  • Delivery time can be shortened – Compared to the measurement method using a conventional hand tool and stone surface plate, the measurement time of a Coordinate Measuring Machine can be completed in a maximum of several tenths. In addition, you can create a program for automatic measurement by a CMM from CAD data.
  • Can be used instead of gauges and jigs – In terms of medium-term costs, the cost of inspection is cheaper with a CMM than purchasing expensive dedicated gauges and jigs for inspection. The 3D measuring machine also supports line-side and in-line measurement and installation.
  • Work after measurement becomes lighter – By combining a height gauge and a surface plate, setup work such as “axis alignment” and “surface alignment” becomes extremely short. Also, if you set what you want to measure, you can measure multiple surfaces without changing the setup.
  • Processing work after measurement becomes easier – You can output the measurement results in the inspection table format. It can be directly compared with CAD data of design values and can be fed back to the manufacturing / development department without paper.
  • No need for advanced measurement skills – You don’t need a high level of skill to measure. In particular, human error is not included in the measurement results.
  • Less fatigue – You will spend less time working. You do not have to change the setup of the measuring object or measuring machine many times.
  • Increased reliability – Maintaining high quality and shortening delivery time will improve the reliability of the company. In addition, since you can use a CMM, you can make an advantage in trading.