A large washer makes a good level for drills, to show whether the hole is being drilled horizontally. Place the washer on the shank of the drill or bit, and then if it feeds forward or backward while the bit stock is being operated it indicates that the bit is tipped upward or downward, respectively. When the bit is held horizontal, the washer will remain stationary. The washer should be free from burrs, and the opening should preferably be turned true.

Fig. 107 - A guide for the stock bit.