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PCB Countersink: special via technology in the process of making PCB boards

PCB Countersink special via technology in the process of making PCB boards

PCB drilling is a process of PCB board making, and is also a very important step. According to the application scenario and the role of different PCB holes will be divided into many kinds, and drilling technology is also different. Today, this article, we will explain a very special hole – PCB Countersink.

What is countersink in PCB?

The term “countersink” refers to the techniques used to create a countersink. Now,A countersink hole is a conical hole that is cut to facilitate the use of a flat head screw. A hole made with a drill or a conical hole cut into a PCB laminate are other names for it.

The main goal is to allow a countersunk screw to lie flush with the laminate surface after being placed and tightened in the hole. A countersink is the term for the cone-shaped hole that was carved into the PCB laminate. Typically, it is utilised to allow a screw’s tapered head to rest flush with the top or bottom of the laminate.

What is countersink in PCB

What is the purpose of a countersink in PCB?

It is primarily utilized to allow the flat head screw to attach and sit flush with the surface for a neat appearance. Most manufacturers want information on the hole diameter in order to assure proper design for production. They also want information on the plating of the hole.

It is crucial to know if the hole has been plate or not since, in certain cases, an unplated hole may be grounded to the framework, which might result in an issue that would need plating to fix. Although countersinks typically have an 82- or 90-degree angle, the client may need to supply the PCB fabricator with various angles.

What’s the PCB countersink dimensions?

A countersink hole might have a variety of angles. Additionally, it includes several common sizes like 60, 82, and 90 degrees as well as the controversial 100, 110, and 120 degrees. However, 82, 90, and 100 are the most often employed.
● Mounting hole diameter (D1);
● Countersink diameter (D2) or Depth;
● Countersink angle (82°, 90°, 120° etc).

What's the PCB countersink dimensions

What is PCB countersink process?

The fitting’s threads may become entangled with minute pieces of metal that are left on the edge of a hole after it has been drilled and tapped. These metal shards will corrode the threads and cause a loose fit. The creation of leakage pathways will also have an impact on how well the pieces are sealed together.

The quality of the construction is crucial in trenchless projects where the piping is buried, since this helps to avoid issues once the installation is complete.

When should you countersink on PCB ?

One may put things neatly using a PCB with a countersink hole. Therefore, it is ideal for compact devices that require tight fitting. Examples of miniature appliances are mobile phones and tiny wearable technology.Making conical holes that fit the angled contour on the bottom of flat head screws with conical heads requires the use of countersinking.

What’s the difference between PCB counterboring and PCB countersinking?

To enable the head of a screw or other fastener to sit flush with, or just below, the surface of the material into which they are placed, countersinks and counterbores serve the same function. The angle at which the bigger hole is bored distinguishes them from one another.

While a counterbore is drilled straight into the material and leaves a level bottom between the counterbore and the smaller inner shaft, a countersink’s bigger hole is tapered at an angle.Despite the fact that counterbore and countersink screws can sometimes be used interchangeably, there are differences in their usage and form, as well as the holes they create.
What's the difference between PCB counterboring and PCB countersinkingThe size and form of the holes are the main distinction between countersink and counterbore screws; counterbore holes are larger and more square to accommodate the placement of washers. Similar to countersinking, counterboring is a technique for embedding a fastener below the work-piece’s surface.

Although the names are occasionally used synonymously, the bottom of the hole’s form is the primary distinction. A flat-head screw’s underside has an angled form, and countersinking produces a conical hole that matches it.

What would be the advantage of a counterbore over a drilled hole?

Due to the socket cap screw head’s force being parallel to the axis, a counterbore often has greater holding power than a countersink hole. Over a wider surface area, the screw or bolt’s force is dispersed evenly. With a countersunk hole, which has tapering sides, this is not the case. As a result, the force generated by the screw or bolt is not distributed equally, but rather down the slope of the hole or at an angle.

Which of the following tool is used for countersinking?

A variety of materials, from those used in common applications to those utilize to cut through very hard surfaces, are available for countersinks. High speed steel, cobalt steel, carbide and carbide tips, and diamond tips are the most often utilized materials.Which of the following tool is used for countersinking
High-speed steel is a cutting-edge material with low cost. It is employed in common metal machining applications.

Tools made of cobalt steel are used often to cut stainless steel and other alloys since they are somewhat tougher than high-speed steel.

Carbide grades endure longer and experience less wear because they are significantly tougher than high-speed steel. There are several coatings available to increase cutter life. Solid carbide and carbide-tipped countersinks fall under this category.

For specialized uses like cutting at extremely high speeds, industrial diamond grades like polycrystalline diamond (PCD) are frequently utilised because of their extremely long service lifetimes.

How is countersink depth calculated?

Before the seam is sectioned, countersink is normally measured using a mechanical gauge at least three points in. In some circumstances, a countersink optical measurement is required. This applies when the optical unit’s resolution is adequate and it is configured to observe the whole seam, including the Countersink. Please let the maker of the double seam inspection system know whether this is something you want and what configuration you require.How is countersink depth calculated
Subtract the countersink diameter from the diameter of the current hole. Since half of the difference is on either side of the hole, divide the result by two. Because the legs of a 45-45-90 are equal, so is the depth (y) at which the tool must be fed.


Above is the content of the PCB countersink, I hope can be helpful. If you want to learn more about via on PCB and some other terms related to PCB and PCBA, then please browse other articles on our website. Also, if you are looking for a PCBA company that can provide PCB manufacturing, design, component procurement, and assembly, then IBE would be a good choice.



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