What is the reason for the quality problem of solder printing machine?

There is a very important link in the SMT assembly line, which is the solder printing machine printing. The quality of the solder paste printing will directly affect the quality of the subsequent SMT processing and the quality of the entire PCBA board. What causes these production defects?

I. The solder paste pull tip

Causes

squeegee gap or solder paste viscosity is too large formation.

Solution

In the SMT chip processing in the appropriate adjustment of the scraper gap or pick the appropriate viscosity of the paste.

II. The paste is thin

Causes

1. The template is thin

2. Scraper pressure is great

3. Poor paste activity

Solution

1. SMT manufacturer operators to select the appropriate thickness of the template

2. Selection of particle size and viscosity of the paste

3. Decrease squeegee pressure

III. The thickness of the solder paste on the pad is not the same

Causes

1. The paste mixing is not average, making the particle size is not common;

2. Template and printing plate is not parallel.

Solution

1. In the SMT OEM material printing before the abundant mixing and solder paste.

2. Adjust the absolute orientation of the template and the printing plate.

IV. The thickness is not opposite, edge and surface burrs

Causes

Can be low paste viscosity, template open hole hole wall roughness.

Solution

1. Selection of slightly higher viscosity solder paste; 

2. Check the etching quality of the template hole before printing.

V. after printing, solder paste to the middle of the pad trapping

Causes

1. Squeegee pressure is too great

2. The positioning of the printed board is not secure

3. Solder paste viscosity or metal content is too low

Solution

1. Adjust the pressure

2. Fix the printing plate from the beginning

3. Select the paste with suitable viscosity

Company Profile

Zhejiang NeoDen Technology Co., Ltd. has been manufacturing and exporting various small pick and place machines since 2010. Taking advantage of our own rich experienced R&D, well trained production, NeoDen wins great reputation from the world wide customers. 

with global presence in over 130 countries, the excellent performance, high accuracy and reliability of NeoDen PNP machines make them perfect for R&D, professional prototyping and small to medium batch production. We provide professional solution of one stop SMT equipment.