For a dose of unadulterated frustration, there’s nothing like finding out that the level you used to frame up that last window opening was totally out of level. Nine times out of 10, you won’t notice until you step back and see the tilt of the sill and header in relation to the other wall framing.
To prevent this scenario from happening to you, get into the habit of checking a level for trueness before using it. This is especially necessary if the level belongs to someone else, or if you suspect that it has been dropped.
The true check is a simple procedure. As shown in the drawing, the level is placed against a flat surface (it doesn’t have to be level), and the position of the bubble is noted. The level is then turned end-for-end. If the level is true, the bubble will come exactly to the same place. This test also applies for checking the vial that reads plumb.
If the bubble isn’t cooperating, the level is off. Adjust it by following steps A-D in the drawing. All you need is a screwdriver that fits the vial’s set screw, a flat surface and a scrap of shim stock.
Jim Tolpin, Port Townsend, WA
