Most Encountered Geometric Manufactured Features In Mechanical Design

One of the most important areas of mechanical engineering is manufacturing. And manufacturing is going on with standards. All the manufacturing tools, machines, workpieces are designed by world standards. These standards can be SAE standards or SI standards, but standards are generally in the role. 

In manufacturing, some manufacturing geometries and features are commonly used as standards. As a mechanic, mechanical engineer, it is very important to be aware of these common geometrical standards. You can find the most common ones in this article. 

Common Manufactured Features

Here is the list of the common manufactured features on different parts and mechanical designed parts.


A keyseat groove on a hub.

Keys are the mechanical elements that are used to attach gears on hubs and cylinders. With keys, attached gears will not slip on the cylinder. 

To attach the keys, keyseats are machined on the surfaces of cylinders, shafts, or hubs. 


Fillets and rounds(Image Source:

Fillets are geometric entities that are created by blending the corners of the intersecting surfaces of the parts. Fillets are standard applications in mechanical design because of various reasons. 

The first reason, fillets are used for removing the molded part from the mold without defects. Without fillets, sharp corners tend to create burdensome cracks and defects while the part is removed from its mold. 

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In general, rounds are confused with fillets. The main difference between the rounds and fillets is; fillets are internal geometries. Fillets are created on the concave surfaces’ corners. But rounds are convex. 

The strength of the casting system can be improved with the addition of rounds to the designed parts. In mechanical design, rounds are generally used at the corners. In general, sharp internal and external corners must be eliminated. 


If there is a hole on a part, the counterbore is a bigger diameter hole that drilled on the smaller diameter hole. The smaller hole and bigger diameter have the same centers. 

Counterbores are designed to attach bolts and nuts inside them. There are standards of counterbores.

Illustration of counterbored and countersunk holes.


Countersinks are similar to geometric features with counterbores. But the bigger hole that recesses around the smaller hole is cone-shaped. 

Tapered screw heads are mounted from countersink geometries on mechanical parts. Just like counterbores, countersinks also have standards and you can add these countersink standards to your geometries. 


Chamfers are used on convex surfaces of mechanical parts for better handling and avoiding sharp corners. Chamfers are also used on cylinders in the same way. 

Illustration of edges, chamfers and fillets(Image Source:


This is another geometric feature similar to counterbore also. But the bigger hole’s depth is much more small compared to counterbore holes. 

Spotfaces on a mechanical element(Image Source:

Various mechanical fasteners needed to be attached to spotface holes. 


Bosses are geometric features on the mechanical parts’ surfaces. They are generally protruded entities above the surfaces. 

Boss geometries for different purposes(Image Source:

Bosses are used for different kinds of purposes on mechanical designed parts. For example, bosses can be used in cam mechanisms. 


A mechanical bushing used as a bearing.

Bushings are generally used for sealing elements on mechanical parts. Also used as guideways and bearing applications are also common in mechanical design. 


Different lug designs for attachments.

Like bosses, lugs are straight rounded tab protrudes from mechanical parts’ surfaces. They are generally used for the attachment or assembly of different mechanical parts to obtain the required mechanisms. 


On cylindrical parts or tubes, they are created as bigger rims or cylinders around a little portion of the parts and tubes to obtain better attachment and mounting to each other. 

A very good flange example.


On an ordinary cylinder, necks are the grooves that are machined on the surface. They reduce the diameter of a cylinder in which portion that necks are machined. 


Knurls on handle of a micrometer.

Knurls are the surface entities that are carved on the surfaces to obtain different patterns. These knurl patterns provide better holding surfaces and more contact areas for better handling of the material. Knurls are generally used for better gripping of knobs and tool handles. 


These are the general design considerations and geometric features that are generally used in mechanical design. While you are making or obtaining different mechanical designs of different mechanical parts, you need to consider these geometric design entities in your design. 

Do not forget to leave your comments and questions below about the mechanical design geometric entities in mechanical engineering!


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