# Measurement Service for Determining Positioning Accuracy on SMT Equipment

## Determination of Squeegee Force on Stencil Printer

• Determination of the dynamic forces acting on the substrate during printing
• objective and independent measurement and analysis certified according to DIN ISO 9001
• Determination of causes for inaccurate squeegee forces and derivation of corrective measures
• Checking the effectiveness of corrections
• Calculation of $$C_m$$ and $$C_{mk}$$ values based on given specification limits
• Statement of conformity to the given specifications taking into account the measurement uncertainty and the given target values
• Detailed and meaningful test report

### Preparation from CeTaQ

• CAD data for creating the processing program taking into account the pressure range and the pressure height
• mobile force gauge for carrying out the measurements

### Preparation from Customer

• executable machining program according to the specifications of the CAD data provided
• Ensuring a good condition of the system to be inspected by prior maintenance and, if necessary, calibration.
• Squeegee of appropriate length
• Table and power supply near the equipment to be tested for setting up the measuring system
• Technical support for setting up and operating the system

### Running the Print Cycle and Measurement

The equipment to be examined is prepared by the technical support, the appropriate program is loaded. The sensor board is then mounted on the printing table and connected to a laptop. The laptop records the force curves during the printing process. Typical are 15-25 cycles per squeegee direction. After completion, the force profiles are analyzed.

### Analysis of the Results

The force profiles of each individual squeegee cycle are extracted from the signal recorded during printing. The average force of each cycle is evaluated in relation to the specifications from the print program.

### Use of the Results to Optimize the Accuracy

In many cases it is possible to derive corrective measures for optimization directly after the analysis of the results. After corrections have been carried out, their effectiveness is checked with a further measurement. Depending on the result, this may result in further measures followed by verification measurements.

The test is carried out several times by varying the nominal forces specified in the program. These should cover the area used in production. Typical scope are 3 runs with changing nominal values.

### Report Writing

On the basis of the final condition achieved, a test report is drawn up after completion of the work. This is usually done after the customer has visited our office. In addition to a detailed description of the final condition, the report contains all steps taken to achieve this condition.

• The measuring system is calibrated on the basis of international standards.
• The method is suitable for all paste printers whose transport system can accommodate the force gauge.
• The time required for a complete examination is usually between 1 and 3 hours, depending on the type of system. Typical is 2 hours.