Final answer:
In thread cutting, a spring pass is generally recommended after every 2 to 3 passes. This step ensures that the threads are accurately cut and cleared of any irregularities, which is essential for maintaining thread quality and precision.
Step-by-step explanation:
When chasing a thread, it's important to maintain the accuracy and quality of the threads being cut. As a general practice, a spring pass should be taken after approximately every 2 to 3 passes. This helps to clean up any irregularities and ensures that the threads are cut to the correct depth without putting undue stress on the tap or die and the material.
Spring passes are particularly vital when working with materials that are more prone to deformation or when high precision is required. They are non-cutting passes that allow the tap or die to realign itself with the threads and ensure that any residual material is cleared out, resulting in a smoother, more accurate thread.
This practice can vary depending on the material's hardness, the size of the thread, and the condition of the tap or die. In some cases, more frequent spring passes may be necessary, while in easier to machine materials, less frequent passes may suffice.