I recently bought a slow speed grinder as I’ve grown beyond weary sharpening A2 steel entirely by hand. If my plane irons were thin Stanley O1 blades, then I would never need a grinder even if the blade was nicked. However, it is what it is and life goes on.
With every new grinder or with every new wheel replacement, you will need to balance or align the wheels. You also may have to periodically balance the wheels throughout the life of the wheel due to dressing, wear and profiling. The balancing of grinding wheels is essential despite dressing them! Skipping this step may cause chatter marks, excessive wheel wear and spindle head wear to name but a few.
When you start the grinder, you may notice that the wheel has a slight wobble. This can be due to the large flange washers not running true. Fixing this isn’t as difficult or time consuming as you may think.
First turn the machine on and look at the wheel to see if there is a wobble. The chances are high that there will be. If there is, turn the machine off, unplug it from the wall, wait for the wheels to stop turning and take the covers off.
Make a reference mark on each flange washer and the wheel to record their original location.
Next, loosen the shaft nut and rotate the flange washer clockwise and the other wheel counter clockwise by ½”.
Tip: If the wheel is new, you may notice the flange washer won’t rotate due to it being stuck to the paper. I used the tip of a flat blade screwdriver to strike the flange washer, a light tap is all that is needed to unstick it from the paper.
Tighten the shaft nut by hand and rotate the wheel by hand. If you don’t feel confident that you will observe any change, then tighten the shaft nut and turn the machine on. If there is still wobble in the wheel, turn it another ½”. Keep doing this until you’re satisfied. You could spend an eternity finding that sweet spot, but at some point you will have to stop and say it’s good enough for my purpose. A small amount of wobble is fine.
The final step is to dress the wheel. The centre bushings “roughly” centre the wheel on the shaft. Inaccuracies in the manufacturing process may cause fluctuation in the wheel and to address this, a wheel dresser can be used to make the wheel run true.
Place the wheel dresser on the tool rest angled upwards with the edge of the wheel dresser facing the wheel. Slowly bring the wheel dresser to the stone until you hear the untrue side touch the dresser. As you apply light pressure, the face of the stone becomes true.
Some things to be aware of:
The left side shaft nut has left-handed threads and so the nut is tightened counter clockwise. The right-side shaft nut has right-handed threads and is tightened by rotating it clockwise.
Do not over tighten the shaft nuts. Doing so can cause damage to the wheel and the flange washers. A light touch is all that is needed. The direction of travel will keep the nuts tight.
When buying a new wheel make sure the R.P.M. rating is greater than the grinder’s motor. The outer diameter of the wheel must be according to the size specification of your grinder. The bore diameter of the wheel must be the same as the original wheel.
Do not remove the labels on the sides of the wheels. They help to spread the holding pressure of the tightened nuts on the grinding wheel flanges.
Applying the entire face of the wheel dresser to the stone without the support of a tool rest may introduce deeper grooves and further untrue the stone.
Troubleshooting as is in the manual
If the adjustment of the flange washers does not make the wheel run without side to side oscillation, then remove the wheel and flange washers and check the shoulder on the motor shaft at the point where the flange washer seats against it. A slight burr on the edge of the shoulder can stop the flange washer from seating properly. The burr can be removed using a file to smooth the edge of the shoulder. Look for any roughness on the surfaces of the flange washers and smooth these spots on sandpaper placed on a flat surface. Then replace the wheel, re-adjust the flange washers, and dress the wheel.
With wheels properly aligned,this is a wonderful machine that serves its purpose in eliminating the drudgery of sharpening A2 plane blades. With the further aid of an after-market tool rest, you’ll have one powerful addition to your sharpening tool kit.