2.Tighten the cap screws, making sure the cen- ter of the rear trimming hole is over the edge of the grinding wheel, as shown in Figure 24.
Center
Wheel
Edge
Figure 24. Rear trimming hole center over
grinding wheel edge (cover removed for clarity).
3.Make sure the grinding wheel cover is secured, turn the machine ON, and wait for the machine to reach full speed.
4.Insert the collet holder and bit into the rear trimming area so the pins fit into the notch on the collet holder as shown in Figure 23.
5.Press the collet holder and bit down, and after about four seconds dip the tip in water. Continue alternating between grinding and cooling until the machine stops making grind- ing noises.
Note: The harder you press down on the collet holder, the larger the back relief will be.
6.Remove the collet holder and drill bit, rotate them 180º, reinsert them into the trimming area, and repeat Step 5.
To prevent getting burned during the next step, do not touch the end of a freshly ground bit, which may be hot.
7.Remove the collet holder and examine the bit.
Back Relief
Figure 25. Back relief on standard bit too small.
8.Remove the bit from the collet holder.
To create a split point bit:
1.Follow Steps
2.Continue lowering the adjusting block, grind- ing the drill bit on both sides, examining it, and carefully adjusting the block down until the back relief looks like the example in Figure 22.
Be careful not to lower the adjusting block too far, or the point may oversplit, as shown in Figure 26.