Before applying threads in SOLIDWORKS, it is important to understand the methods of adding threads, as well as the advantages and disadvantages of each method. This article discusses how to apply threads in Solidworks and how to choose which method to use.
There are two main types of thread that can be applied in SOLIDWORKS, cosmetic threads, and model geometry threads. Deciding which of these methods is most suitable for your application is the first decision to make.
What are the differences?
Cosmetic threads are annotations. They describe the attributes of a hole or an external thread so modelling of the thread is not required. Because cosmetic threads are annotations and do not add model geometry, they are lightweight and do not add rebuild time to the model.
Cosmetic threads can be added in two ways, automatically as part of a hole wizard or hole series feature, or as an annotation. Insert > Annotations > Cosmetic Thread
When to use Cosmetic Threads…
Let’s take the example of a plate with a number of tapped holes. The process for adding these holes during manufacture is to drill the tap holes first and then add the thread using a tap. As the thread is defined by the tap tool, there is no need to model the thread. All we need to know is what thread should be applied and ensure this is annotated on the 2D drawing. This example lends itself perfectly for use with a cosmetic thread.
Model Geometry Threads
There is no specific ‘thread’ feature for applying model geometry threads to a model. Most commonly, a sweep feature is used to either cut material away or add material to the model. Model geometry threads require more machine resources than a cosmetic thread and will significantly increase model rebuild times.
When to use Model Geometry Threads…
Model Geometry Threads should be used where the part being modelled requires the thread as part of the tooling process. For example, if an external thread is being added to the neck of a bottle and this detail is to be machined into a mould tool, the thread should be modelled.
How to model a Thread in SOLIDWORKS…
- Create a plane at the point that you want the thread to start
- Sketch a circle that defines the starting diameter of the threads helical profile
- Add in a helix Insert > Curve > Helix/Spiral
- Create a plane at the end point of the helix
- Sketch the thread profile on the plane at the end of the helix
- Sweep the thread profile along the helix
Why can’t I see cosmetic threads?
Cosmetic Threads can exist within a model without being shown. If a Cosmetic Thread has been added but cannot be seen, make sure they are enabled.
R>Click Annotations folder > Details > Enable Cosmetic Threads and/or Shaded Cosmetic Threads