Allen Timmons Centerless grinding is the method we use at Western Steel & Wire to achieve tight tolerances and non-standard diameters. We are experts in this method and believe in its ability to produce consistency and quality for our customers. To understand centerless grinding better, read our other post on cylindrical grinding basics.
With centerless grinding, there are 3 methods used to feed the workpiece and obtain varying end results.
Method 1: Thru-feed Grinding
Thru-feed (through-feed) grinding is highly efficient, as it allows the operator to move the workpiece from one end to the other without changing direction or hand placement. This type of feed method is ideal for uniform cylindrical objects like wire rods and mandrels. It can be used to create any size diameter and produces excellent consistency. Remember this method as pushing the object all the way through the grinder in one fell swoop.
Method 2: End-feed Grinding
End-feed grinding is slightly more cumbersome but with repetition operators can become incredibly efficient. Set up is the same in this method, but instead of feeding the workpiece from one end to the other it is fed in and out from the same place. End-feed grinding is best for tapered pieces, where you need control of the diameter to create a non-uniform result. Remember this method as a push and pull, requiring more control.
Method 3: In-feed Grinding
In-feed grinding is the more complicated of the three. Here, the workpiece is held stationary against the regulating wheel (rotating, but not moving horizontally). This provides enhanced control of the grinding wheel with the ability to create complex shapes. Therefore, in-feed grinding is the only centerless grinding method that allows operators to shape workpieces freely and must be used for non-uniform objects that involve more than single curvatures.
Internal vs. External Centerless Grinding
Though centerless grinding is mostly associated with external grinding to create specific outside diameters, it can be used internally as well. By adding additional rollers, holes and tubes can be formed using centerless grinding. Though there are many alternatives to internal grinding, the centerless grinding approach can be efficient for operators who already use external centerless grinding. It requires additional setup and switching rollers can be time consuming, but in the end may be worth the investment should you need frequent, uniform holes and tubes manufactured.
Centerless Grinding Results for Wire Products
When it comes to wire, centerless grinding is the best method of the cylindrical options as it creates accurate and consistent products. At Western Steel and Wire, we use thru-feed and end-feed methods to create wire products of varying diameters and lengths. Our products include:
- Thru-feed results of .030” to .600” OD, +/- .0002” tolerance with lengths up to 20’
- End-feed results of .030” to .600” OD, +/-.0002” tolerance with end grind up to 12”
- All products are 16 Ra finish or better
