# How to distinguish the countersinks from counterbores

PCB generally need to include screw holes for fixing. as such, special holes, like countersinks and counterbores. incorporated into the boards to allow them to fixed in place using different types of screws.

## What are the countersinks and counterbores

A countersink is a cone-shaped hole that cut into the PCB to allow the flat head of a socket cap screw to fit flush. with the surface of the board. A counterbore is a cylindrical flat-bottomed hole that designed to house a hex head. or socket head cap screw to used to secure a PCB board.

Countersinks and counterbores serve the same purpose. to allow the head of a screw or other fastener to lie flush with. or below the surface of the material into which they inserted. The difference between them is the angle at which the larger hole drilled. A countersink's larger hole tapered at an angle. whereas a counterbore drilled straight into the material and leaves a flat bottom. between the counterbore and the narrower inner shaft.

Countersink BitsSince a countersink is not drilled straight into the material. we need to know the intended angle. For all the math nerds out there, you've no doubt noticed the major hole diameter and the angle form a triangle. The depth the countersink will drilled predetermined by the angle, major. and primary diameters. but listing your expected depth is a good reality check.

The chamber angles that are commonly used for countersinks are 82°, 90° and 100°. while a counterbore has a 0° chamber angle but is vertical. The information needed for each type is almost identical with a few exceptions. A counterbore, by definition, drilled straight down with no taper, so we don't need to know the angle

A counterbore is more of a cylindrical flat shaped hole. The hole formed has a flat bottom and allows a screw or fastener with a flat underside to fit. Also, the instrument that used to create this feature is also known as a counterbore. The word will used .

## countersink symbol

A countersink (symbol: ⌵) is a conical hole cut into a manufactured object, or the cutter used to cut such a hole.

ASME Y-14 Counterbore Symbol Counterbore Symbol. This symbol denotes counterbored holes used to recess fastener heads (fillister, socket). Countersink Symbol The symbol denotes a need for countersunk holes. used to recess flathead. and ovalhead fasteners.

In Dimension Text Editor, Click Symbol Ribbon, and then Click Other. Then You will get Character map Dialog box. If you change Font to GDT, You will see Counterbore and depth symbols.

## countersink  vs  counterbore

A countersink hole is a normal right cylindrical. through-hole with an more right conical section removed on the top. The cone angle is 82 or 100 degrees. Why do you need Countersink?  Makes it possible for a flat head screw to sit flush with the surface to make for a very clean look and installation.

A counterbore is a cylindrical flat-bottom hole that cut. that also allows for a socket cap screw (has a flat head) to used. The socket cap screw usually has an allen wrench drive (hex) hole.Why do you need a Counterbore? It needed for much more secure and stable mountings.

Countersinks and counterbores are not anything unique to printed circuit boards. They  used in a variety of manufacturing of both metal, wood and other materials. A common usage of countersink or counterbore holes is to allow the head of a countersunk bolt. or screw, when placed in the hole. to sit flush with or below the surface of the surrounding material.

Counterbore and countersink screws are sometimes used. but there is a difference in the shape and usage of the screws and holes they make. The key difference between countersink. and counterbore screws are the size and shape of the holes. counterbore holes are wider and more square to allow for the addition of washers. Counterboring is a means of setting a fastener below the surface of the workpiece. like countersinking.

Although the terms are sometimes used. the main difference lies in the shape of the bottom of the hole. Countersinking creates a conical hole matching the angled shape. on the underside of a flat-head screw.

This conical hole can be shallow. with the screw resting flush with the surface of the workpiece when driven in. or it can made deep enough that a wood button or plug can installed. above the screw once it has been set at the bottom of the cone.

Counterboring creates a flat-bottom hole. which allows the head of a screw or bolt with a flat underside to rest in the counterbore, often atop a washer. While the hole above a set flat-head screw is usually the same size as the screw head. the hole created for a counterbore is larger than the head. which allows room for both the washer as well as the driving tool, such as a socket wrench.

In a word, A countersink is a cone-shaped hole that cut into the PCB. to allow the flat head of a socket cap screw to fit flush with the surface of the board. A counterbore is a cylindrical flat-bottomed hole that designed to house a hex head. or socket head cap screw to used to secure a PCB board.

### different process

The practice of making a countersunk hole known as countersinking. Now, a countersunk hole may come in different sizes of angles. It includes the standard sizes of 60, 82 and 90 degrees alongside the less popular 100, 110 and 120 degrees. But, the most used degrees are 82, 90 and 100.

While the only angle applicable to a counterbore is a vertical zero degrees. it is as effective as a countersink. It is important to note that when working with a wooden surface. if you fail to countersink first but end up forcing the screw into this surface. not only will the wood’s stability and strength compromised but your work will so be an eyesore.

It is because the wood fibers will crack and become dented if not wholly damaged. It is much easier to counterbore a wooden surface. this is because counterboring does not need precision and accuracy in the angles. Also, in a counterbore. all the hole needs is a screw with a flat underside or one with a socket head can fit with the surface or washer.

Counterbore used for a single purpose. while countersinks, due to their different angles, have different purposes. A counterbore is often like an enlargement of a small coaxial hole. while a countersink is a conical version of that.

Use it when you don’t want the head of the fixture, or screw the bolt forward from the HDI surface you are working on. But, countersunk holes have different styles because of their different angles. With countersinking, all your screws can have the same depth.

### different Symbol

In drawing or design, symbols used. as a representation of the actual material or technique. With symbols, there is room for dimensional consistency and tolerance of specifications. Also, is much faster and also easier to write the symbol of material. or quantity as opposed to spelling it out with actual words on a drawing. It is not only against drawing protocol but will also make your work clustered.

Symbols represent basic protocol in drawing, design or mathematics. In a building or house plan drawing, symbols used as a faster means of conveying information. Here, the symbol of a countersink and that of a counterbore represented. It is often side by side with the symbol of a diameter and accompanied by a numerical value.

A countersink symbol looks like the letter V. When you think about it. when you look at a countersunk hole from the side it resembles the letter V.

The symbol of a counterbore has likened to an incomplete square with an opening at the top. In technical drawing, this symbol formed by taking the side view of the countersink. and counterbore holes.

Both symbols used in drilling designs. With the symbol of diameter, they used to show how wide or how deep a hole meant to be. These designs  interpreted by a builder. who works based on the information provided on these designs. A counterbore symbol used to define counterboring operations. while that of a countersink is for countersinking fastening operations.

### different  Drill Bits

You could create several holes when using a drill bit. depending on the diameter that required and the thickness of the material. But for a counterbore and a countersink, They are hole drills, so the process created by them.

The drill bits are the instruments used for drilling. or creating either a countersink hole or a counterbore into the surface of a material. which in this case is a print circuit board, PCB. Both types of holes use different materials for their fabrication.  the aim is to create a hole where a screw or fastener can sit flush within the washer or workpiece.

It done to completely hide the entire length and axis of the fastener or screw in the countersunk hole. or counterbore. Because of the difference in their cavity, (one is flat, and the other angled). different materials used for their fabrication.

For counterboring, a cylindrical hole bored into the material’s surface. This hole has a large diameter at the head and a smaller one down below. It is because the screw or fastener meant to sit in the hole. and prevent the two surfaces from separating when joined. The larger side of the hole fits the head of the fastener while the smaller one accommodates its shaft.

But, countersink drill bits come in different styles. and sizes to accommodate the different angles. and also for different types of projects. There are about four different types of countersink drill bits in the picture above. These are the fluted bits, the cross-hole countersink, the rocker pro. and the flip style countersink.