Get to know the Multi-level /Step Stencil

What is Multi-level /Step Stencil?
Partial STEP-UP Stencil and partial STEP-DOWN Stencil are carried out on the steel sheet to make the same printing on the same stencil so that different areas can obtain different thicknesses of solder paste. According to the performance of components, the size of the connection end and the lands, it can accurately control the amount of solder paste which applied to the different components are accurately controlled to make the solder paste printing process efficient and accurate. A Ladder stencil recommends the use of a squeegee for better results.
1. STEP-DOWN STENCIL
For precision PCBs with IC pitch 0.4mm and large-sized patch materials such as card holders and earphone holders, thicker steel sheets can be used to achieve the amount of tin in the headphone holder, and Precision ICs cannot adhere to the tin and generate other undesirable phenomena. The precision IC can be effectively controlled by STEP-DOWN STENCIL, so that the amount of solder paste can be accurately applied to different components to make the solder paste printing process efficient and accurate.
2. STEP-UP STENCIL
STEP-UP STENCIL is mainly for large materials such as USB, earphone holder, card holder, module, button, etc. For example, a piece of precision material on a PCB needs to use 0.1mm thick steel sheet, and the amount of tin in individual large materials which fail to meet the standards will result in undesirable phenomena such as lack of tin, virtual welding, and false welding. The position of the large material can be locally thickened by 0.15mm, and the convex step layer is reflected on the steel sheet, thereby increasing the amount of tin in the specified material, effectively controlling the occurrence of undesirable phenomena, and accurately applying the solder paste to different components，making the printing process of solder paste efficient and accurate. Partially thickened steel mesh can also overcome the problem that some parts are not flat enough.

Technical Introduction
To increase or decrease the amount of solder paste for one or some specific devices! We can achieve the thickening, thinning and multi-layer steps of the specified position on the same steel grid, namely 0.08MM 0.1MM 0.12MM 0.15MM 0.2M 0.25MM 0.3MM.
The production of Step Stencils
The Step Stencils needs to be combined by etching process and laser process.
1. Chemical etch
Process flow: Data File PCB→ Film Production → Image Expose → Image Develop → Copper Etch → Steel Sheet Cleaning → Steel Sheet Draining
Features: The step steel sheet solves the problem of an excess of tin and lack of tin in the patch. And it is the only process that can produce step steel sheets.
Disadvantages: overmuch production links, much of cumulative errors, time consuming, rough surface, not environmentally friendly, expensive.
2. Laser cutting
Process flow: fix step steel sheet → take coordinates → laser machine coordinate alignment → laser cutting → grinding → sealing net
Features: high precision of data production, small impact of objective factors; trapezoidal opening is conducive to  demoulding; can be used for precision cutting.
Disadvantages: It is difficult to take the coordinate alignment operation, thus resulting in slow speed.  
To quote Step Stencil, just click here and write your demand on the No.3. red box( see pic4) or consult to your salesman.



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