The Automatic Surface Grinder for You!

Posted on Sep 9, 2020

5
The Automatic Surface Grinder for You

The automatic surface grinder is used to obtain a smooth and fine finish on metallic or non-metallic materials. It uses a circular rotary grinding wheel that remains stationary (but rotates) while the feed table (with the job attached) rotates with a reciprocating motion (left and right) under the grinding wheel.

How to use a surface grinder:

The automatic surface grinder is used to obtain a smooth and fine finish on metallic or non-metallic materials. It uses a circular rotary grinding wheel that remains stationary (but rotates) while the feed table (with the job attached) rotates with a reciprocating motion (left and right) under the grinding wheel. The specific amount of material to be removed is determined by gently touching the work with the rotating grinding wheel and moving the grinding head a specified distance. W A R N I N G - If a grinding wheel can exceed the maximum safe speed, it may fall apart and cause injury to the operator and damage to the grinder!

 

On a hand-held surface grinder, you then move the table left and right with one handwheel while the cross feed is done with the other handwheel. Automatic plane grinder in 2 or 3 axes and on an automatic plane grinder, you will be able to automatically move the table left and right during automatic cross feeding. All you need to do is set the down feed and pitch.

Typically, surface grinders can grind in the range of .0001 to .0002, but not all surface grinders are created equal. The cheaper models may not withstand the accuracy of a tool shop, but can be effectively used for sharpening punches, dies, or for workshop work. More expensive models will use higher quality spindle bearings and other components and be better able to achieve accuracy in the tool shop.

To use a surface grinder, you need to choose the right grinding wheel for your job. There are different discs that are best suited for grinding:

Read More: How to pick the best Surface Grinding Wheel

* RC 50-68 high speed steel

* Series 400 Stainless steel

* Soft Steels RC 30-45

* 300 Series Stainless

* Cast Iron: Ductile & Gray

* Nonferrous Alloys

In each of the above categories, you will have to specify the type of wheel when deciding whether you need a heavy (> .004), moderate (.002-.004), or light (.001) removal characteristics. You also need to select the grain size. Grit 46 for general use, grit 60 for commercial finishes, grit 80 for fine finishes and grit 120 for very fine finishes.

After selecting the correct wheel for the job, visually check for damage or cracks. If no damage is found, install the disc on the plane grinder by carefully tightening the left spindle nut with a spanner. Make sure to attach the wheel cover, put on the safety glasses, and then turn on the spindle. Stand back and let the spindle run for 1 minute to make sure the grinding wheel runs smoothly.

After machining the grinding wheel, it is not recommended to turn off the spindle, because turning off the spindle will require reworking the grinding wheel, which will result in loss of some alignment.

You are now ready to dress the grinding wheel with the diamond single point dressing tool which is placed and held by the magnetic chuck. A small amount of the grinding wheel must be cut off the diameter so that the wheel turns concentrically. Place the diamond dresser under the rotating wheel and carefully lower the grinding head until it just touches the dresser. Use the cross feed (y axis) to pull the diamond dresser along the rotating wheel. Lower the grinding head by 0.002, then slide the diamond dresser along the rotating wheel. Repeat until the grinding wheel is clean and running concentrically.

After the wheel is ready and the concentric operation is started, you will be ready to gently touch the work (using the spark method or styling fluid). Then set “zero” on the down feed handle, slightly raise the head to clear the work, then the cross feed handle to clear the work away from the wheel. Then move the grinding head a distance of no more than 0.005. The amount of material removed will determine how far crossfeed can be delivered per passage.

Advantages of surface grinding:

• Very hard or abrasive materials can be grinded

• High degree of dimensional accuracy

• Creates a surface texture with a very fine finish

• Tooling is cheaper

• Holding is easier with the magnetic holder

• This can be done automatically

In short, you will most likely need a surface grinder if you need precision sanded surfaces, whether for a high-quality surface finish or for critical dimensions.

Grinding is the process of removing metal by using abrasives that are combined to form a rotating grinding wheel. When the moving abrasive particles come into contact with the workpiece, they act as tiny cutting tools, and each particle cuts a small chip from the workpiece. A common misconception is that abrasive wheels remove material by friction; in fact, the process is as much machining as drilling, milling and turning of a lathe. The grinder supports and rotates the grinding wheel, and often supports and positions the workpiece in proper relationship to the grinding wheel.

The grinder is used for roughing and finishing flat, cylindrical and conical surfaces; finishing of inner cylinders or holes; forming and sharpening cutting tools; grabbing or removing rough projections from castings and moldings; and cleaning, polishing and polishing of surfaces. It used to be just a finishing machine, modern production grinders are used for complete roughing and finishing of certain classes of work. Grinding machines have some special safety precautions that must be observed. These are in addition to those safety precautions described in Chapter 1.

 

GRINDING MACHINE SAFETY:

Grinders are used daily in the machine shop. To avoid injury, be sure to follow the precautions below.

* W A R N I N G - If a grinding wheel can exceed the maximum safe speed, it may fall apart and cause injury to the operator and damage to the grinder!

* Wear safety glasses for all grinder operations.

* Check grinding wheels for cracks before assembly.

* Never use grinding wheels at speeds exceeding the recommended speed.

* Never adjust the workpiece or the fastening elements while the machine is running.

* Do not exceed the recommended depth of cut for a grinding wheel or machine.

* Remove the workpiece from the grinding wheel before turning off the machine.

* Use appropriate disc guards on all grinders.

* On bench grinders, adjust the tool rest 1/16 to 1/8 inch from the wheel.

 

TYPES OF GRINDING MACHINES

Grinders from the simplest to the most complex can be divided into tool grinders, cylindrical grinders. and surface grinders. The average machine operator will mainly deal with bench and floor grinders, tool grinders. and Reciprocating Surface Grinders.

0Inquiry Item Contact MTS