What is the difference between countersinking and counterboring

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Plated-through slots. Prepregs, cores, foils. PCB price composition. Design rule check. Order Guide. Quality guarantee. Method of payment. Shipping method guide. It should be noted that the hole created by a counterbore is normally larger than the head of the screw which allows for a washer to be placed.

Bothe countersinking and counterboring are done co-axial to the screw hole, the difference in their geometry. The cutting tool used for machining countersink hole is called a countersunk or a countersink bit.

The 90deg countersink tool is also used to chamfer hole edges. You can use a counterboring tool, end mill, or a flat drill to create a counterbore hole.

This depends in large part on what material you are using to drill the hole. For metal and wood , both can be used to equal effect. It is why many people think of a counterbore and countersink as much the same thing with unimportant differences. However, with a printed circuit board the differences become more pronounced. Because circuit boards have holes, how they are created is important to their function.

It is why you need to know the difference when drilling into a printed circuit board. A countersink is well-suited for printed circuit boards that will be placed in a device where space is at a premium. This is because the conical-shaped hole that is created for the countersink requires less depth and the flat screw-head surface can be flushed to the surface of the PCB.

Another advantage is that countersinks can be placed with greater precision which is important when working on small circuit boards such as those found in smartphones and watches.

Countersinks can also be added with greater speed, making them preferable in most repair situations. However, a counterbore has its place on printed circuit boards as well. While it does require more space and will not leave as smooth a surface compared to a countersink, it does create a stronger connection. You use a counterbore when you want to create a socket feature that needs to connect with strength and durability to last. For a given screw size, the counterbore usually has more holding strength than the countersink.

On the other hand, the force delivered by the countersunk screw is dispersed at an angle. The set-up is such that initial drilling and countersinking happens in one working step. There exist some distinct differences between the countersink and counterbore.

We have highlighted some of these differences, here they are below:. The shape of the hole produced by a counterbore is straight, while that of a countersink is V-shaped. Also, you could say that the counterbore is cylindrical, while the countersink is canonical. The key difference between countersink and counterbore lies in their shape. Thus, from physical inspection, you should recognize both hole type.

It is worthy of note that a countersink produces a narrower hole than its head. On the other hand, a counterbore is the same diameter all through. Figure 5: Threaded and Un-threaded Counterbore showing its cylindrical shape. Due to the nature of the countersink or counterbore, the type of fastener used automatically differs. Countersink will always have canonical-head fasteners while counterbore has flat bottom fasteners.

Examples of counterbore fasteners are hexagonal head screws and bolts, nuts with end bolts, etc. More often than not, wood as a material is quite easy to force-fit canonical head fasteners.

It automatically makes the essence of countersinking useless in woodworks. Hence, for metals, PCBs, and other less flexible materials, countersinking is best adopted. Meanwhile, counterbore is more synonymous with wood but also harder to carry out too. The reason for this is because counterbore usually has much larger heads. The simple tool used to form a countersink is also called a countersink. However, to eliminate confusion, it is sometimes referred to as a countersink tool.

These tools come as either manual or power-driven. Your usage and application should guide which version you purchase. Heavy jobs require more power to drive deeper. All you need do is, consider the complexity of your job and purchase a good set with different sizes. Primarily, once your choice of a fastener is a tapered one, then countersink is compulsory. More so, a countersink will ensure that your fastener can go full length into the workpiece.

Conclusively, a countersink adds more aesthetics to your job and averts likely cut or tear to the skin or clothing. A rare case of having a fastener not long enough can be solved easily with a counterbore. The counterbore proffers a solution by ensuring that the hole is sufficient to fasten only. Unlike the countersink, a Forstner bit produces a counterbore. These bits come in various diameters and make precise holes with straight edges.

Honestly, no method is the easiest; both countersinking and counterboring require a similar effort.