Gang type tooling offers fast, accurate, and cost-effective machining on Swiss-type lathes. Turret type tooling offers flexibility and easy tooling setup.
Which type of tooling is the right for the job?

Previously, we discussed 5 key differences between Swiss-type lathe and conventional lathes. Swiss-type machines use multiple tools to perform operations on the part inside a cycle. Cutting tools are changed and brought into contact with the workpiece with the help of the tooling mechanism.

In this article, we will talk about the importance of selecting the right tooling type. Read on to find out details of available tooling types and their impact on the end-product quality and cost.

In most of the modern lathes, the tooling mechanisms come in two distinct configurations

turret type

Turret type tooling holds a set of machining tools on a rotary indexing toolholder. Tools are selected by rotating the mechanism until the correct tool is in its place. 

gang type

Gang type tooling includes a row of tools on a linear slide. Tools are selected by linearly displacing the slide. 

Which type of tooling is the right for the job? 

To answer this question, we need to take into account the nature of the application and the machining part. Before diving into a detailed analysis of each type of tooling, let's keep in mind the simplified rules of thumb. 

• Use the gang type tooling when machining shorter parts with a small diameter using a limited number of tools - focus on speed and productivity.

• Use the turret type tooling when machining long or large diameter parts that need tailstock support - focus on flexibility.

Top Factors to Consider When Choosing the Tooling

1. Speed

   Machining cycle is shorter on the lathe using Gang type tooling than on the one using Turret type.

   During the machining cycle, tools change depending on the operation to be performed. Tools are replaced as follows; 

   1. Retract tooling mechanism away from the part;

   2. Slide (gang) or rotate (turret) tooling mechanism until the right tool is in place;

   3. Place the tool back into contact with the part. 

   In this sequence of operations, gang type tooling is significantly faster.  

2. complexity and cost

   Gang type tooling is simple in construction, has fewer moving parts, and costs less than a turret type.

   Turret type tooling incorporates a lot of moving parts in its construction. Generally, it is more difficult to transmit the rotary power to the tool positions on a rotating turret. Turrets tend to be bulkier than gang type. Complexity in construction, number of different parts, and material utilization make turret type tooling more expensive.

3. changeover

   The changeover is faster for Gang type tooling.

   On a gang type tooling, the tools are more accessible to the human operator. It is easier and more convenient to change tools on the toolholder. Even when cutters need to be replaced inside the machining cycle, it takes much less time to switch between tooling in gang type tooling than in turret type. As an additional advantage, the entire block of tools can be removed and used again when completing recurring orders.

4. accuracy

   Simplicity in the construction of gang type tooling prevents the tolerance stack-up due to moving components, allowing the machining with greater accuracy than turret type tooling.

   Many different factors dictate accuracy. Some of these factors are typically tooling related, namely, the number of moving parts in the tooling construction and distance traveled during the tool switch up. The tool needs to make contact with the workpiece at a precise location along the Y-axis to achieve maximum accuracy. Every additional moving part inside the tooling mechanical configuration introduces clearances and backlash that deteriorate accuracy. Likewise, the tool should cover the least possible distance before it comes into contact with the workpiece to reduce any positioning induced errors.  

   Turret type tooling increases the flexibility of machining;

   1. Turrets can hold a large number of tools; 

   2. Tools can be reprogrammed to cut different parts; 

   3. It is possible to use tailstock for machining of long and thin parts;

   4. Parts with a larger diameter can be machined.

5. programming and initial setup

   Turret type tooling is simpler to program and easier to set up initially. 

   The gang type tooling requires careful consideration of clearance when programming the tool change. This tool arrangement increases the risk of crushing the tool into the part when machining different sections with different diameters.

   The initial setup on gang type tooling is complicated. Every time there is a new tool involved, the machinist needs to position the tools, probe them, and make a test cut. Whereas, with turret tooling, it is enough to load the machines and simply set them up with a tool setter.

Conclusion

As the manufacturer's goals for increased productivity keep getting higher, we continually strive towards solutions that can deliver faster and better quality machining. Faster spindles, better mechanical construction, and advancement in control have drastically increased the material removal rate of Swiss-type lathes. 

The most recent advancements in tooling technology have additionally decreased cycle times by employing gang type tooling. Gang type tooling shortens the machining cycle time by reducing the time needed to switch from one tool to another. A quick changeover capability further increases productivity by allowing the complete set of tools to be quickly interchanged with another tool block for a predefined and recurring job. Gang type tooling has a simple construction and few moving parts, which makes them highly accurate and cost-effective.

On the other hand, for applications that are more in the domain of conventional lathes, the turret type tooling offers flexibility and quick initial setup advantages. Long and thin parts that need the support of tailstock, as well as, the pieces with a larger diameter, can be easily machined using turret type tooling.

We at Turntech Precision provide the best quality parts machined on the Swiss-type lathes equipped with gang type tooling. Utilizing the advantages of these machines, we can provide the best quality products to our customers in a variety of industries.

Contact us today with your inquiries.