Keep Your Fixture Options Open with 2-Inch Grid Patterns

By: Alvin Goellner, Workholding Product Sales Manager, Nick Rupprecht, Business Unit Manager

How a part is held and cut during a machine process determines what workholding arrangement is best for manufacturing process stability, efficiency, and safety. However, the task of making workholding setups on machining centers has its challenges. A 2-inch-by-2-inch grid pattern is a common configuration that keeps your fixturing options open, simplifies setup, and increases throughput.

2-inch grid patterns are common in modular fixturing setups and allow for a maximum number of mounting locations. They provide a universal solution for machine shops that:

• Have a lot of one-part runs or one-time jobs. 
• Have a lot of small production runs that do not repeat on a regular basis. 
• Require rapid setup for short-notice production runs. 
• Create a lot of prototype parts that are often changed or redesigned. 
• Need to respond to orders as they are received, instead of shipping parts from inventory. 
• Need to fine tune tooling ideas before final production.

Grid patterns also allow shops to incorporate popular brand components, such as Carr Lane, into their workholding setups. Sub plates and tombstones that don’t feature a grid pattern may need to be modified for each new application.

2-inch grid patterns provide flexible and adaptable solutions that allow you to precisely move and shift components around for different setups and applications--especially for one-of or pre-production parts needed for customer samples.

Another advantage that 2-inch grid patterns provide is quick and easy setup with less tool changes. Fixtures won’t have to be indicated each time, and products such as precision dowel screws can easily locate and mount components on the grid with high repeatability. The precision location that the dowel pins provide allows the machinist to quickly change the machine to a new workholding configuration. They can be confident in the location of the workpiece instead of spending time on additional setup and indicating multiple parts.

Grid-pattern systems also come in two styles:

• Alternating dowel holes and tapped holes
• Multi-purpose holes

The alternating-hole style doesn’t have as many advantages as the multi-purpose hole style; for example, multi-purpose holes feature both alignment bushing and threaded insert in the same hole. This permits each hole to serve as an alignment hole, mounting hole, or both.

Accessible fixturing options, set-up versatility, and adaptable solutions all help save time during a machining process. 2-inch grid patterns create a “modular g-code” that relies on the positioning grid of the tooling plate. This reduces the potential for errors by allowing quick-swap fixturing setups.

2-inch grid patterns are just one aspect of workholding. There are other areas that focus on the material being cut, tolerance requirements, workpiece shape and dimension, and frequency of change-over.

To learn more about theories, systems, and applications for advanced workholding, be sure to subscribe to Workholding Wisdom below and please contact us with any questions you may have!