Blanchard grinding has typically been a manual process for many shops. The simplicity of a Blanchard makes the operation of the machine easy to learn and easy to run. The old dials and handwheels found on Blanchard grinders still work well and get the job done. That being said, there’s an even easier way to run a Blanchard through the addition of a CNC control.
Blanchard began adding CNC controls to their machines in the 1990s. Until then, Blanchard surface grinders were manual machines. These early controls offered by Blanchard were plagued with issues. Often, many shops will shy away from Blanchard grinders that have the original CNC controls on them due to their reputation. Thankfully, CNC controls have come a long way since the 1990s.
When Bourn & Koch acquired Blanchard in 2004, we immediately began building new Blanchard grinders and remanufacturing their machines. Since then, we have offered Fanuc CNC controls for our machines, starting with the Fanuc Powermate and upgrading to the Fanuc 35i. The CNC controls both axes of the machine, X (horizontal table traverse) and Z (vertical grinding head travel). The addition of CNC allows for very precise control over the grinding head downfeed to .0001″ increments to allow for extremely close tolerances to be held for nearly any workpiece.
Besides allowing for extremely precise grinding, adding CNC to a Blanchard grinder makes the machine easier to operate and maintain. Servo motors now drive the machines axes, eliminating the need for costly maintenance of the gearboxes. With Fanuc’s commitment to support, machine downtime is kept to a minumum and spare parts are readily available.
CNC programming for Blanchard grinders is easy to learn. Standard M & G code is used to program machine cycles for repetitive jobs. A standard grinding program is provided with all CNC Blanchard grinders that can be easily edited by the operator or programmer. Numerous programs can be written and saved for later use. For high-mix, low volume work the MPG handwheel allows the operator to run the machine manually just as you would with the big, old handwheel that Blanchard operators are used to.
A new and unique function offered for our Blanchard grinders is Teach Mode. This mode allows for fast programming of auto-cycle by “teaching” the machine where the start of the grinding cycle is. The operator moves the grinding head to the start position manually and programs in an offset to compensate for wheel wear. The auto cycle performs rough and finish grinding along with a programmed spark-out cycle and auto-demag of the chuck. Once the workpiece is “taught” to the machine, the program can be run simply by pressing cycle start on the control once the workpieces are loaded onto the chuck.
Another great function of the CNC control is a programmable spindle load meter. This is a standard feature on all Blanchard CNC grinders. The spindle load meter displays the load on the grinding spindle as a percentage. The meter can be programmed in two different modes – feed hold at a programmed spindle load and auto-retract at a programmed spindle load.
Feed hold mode allows the operator to maximize production without damaging the workpiece. Once the programmed spindle load is reached, the machine will hold its position until the spindle load drops below the programmed spindle load. Once the spindle load drops, it will resume feeding the grinding head down until the spindle load is reached or the workpiece is ground to size.
Auto-retract mode allows the operator to program the head to retract once a desired spindle load is reached. This is particularly helpful for ensuring parts are ground to size in automatic or programmed cycles. For instance, the load meter can be programmed to retract the head once idle spindle load is reached. At a idle spindle load, the machine is no longer grinding and your workpiece is ground to size.
For a demo of CNC Blanchard operation, contact us at 815-713-2316. We would welcome you for a plant tour and full demonstration on the operation of CNC Blanchard grinding on one of the many machines we have on our shop floor.