How to Use a Transit Level

Whether you are constructing a fence, small building or a home, a transit instrument will help you in keeping things level. Placing a transit instrument at a benchmark, a place that is used for a consistent height measurement, will allow you to "shoot" a level mark through the cross hairs of the transit. With the aid of a helper, you can utilize the measuring stick that usually comes with a transit and mark in pencil a level line around the posts or studs, and horizontally lay up siding and or fencing. By following a basic set of consistent setup procedures you can use a transit for many projects.

Difficulty: Moderate

Instructions

Things You'll Need:

• Transit tripod
• Transit
• 8 foot measuring stick
• Pencil

1. Set the transit tripod on a level portion of the ground. The ground does not have to be perfectly level. Most transit tripods come with adjustable legs for placing the tripod on uneven ground. You can "eyeball" the mounting plate on top of the tripod for getting it close to setting level.

2. Attach the transit to the mounting plate by screwing the female threads onto the transits male threads mounting base. The four adjustable, level screws legs of the transit should be fully retracted up into the base.

3. Unscrew the adjustable legs of the transit base two at a time. In other words, unscrew the two opposing legs until they just meet the mounting plate of the tripod. Unscrew the other two legs just as the first two. The adjustable screw level legs should just be supporting the transit.

4. Fine tune level the transit by orientating the top bubble level, mounted in the top of the transit body, by placing the long eyepiece parallel to one set of the adjustable legs. Set the bubble in between the two lines of the level by manipulating the screw legs until the level bubble is dead center of the two level lines.

5. Rotate the transit so that it lies parallel to the last opposing screw legs and level the bubble as in Step 4. You should now be able to rotate the transit 360 degrees, and the level bubble should remain perfectly dead center of the two level lines. The transit is now setup to shoot a level mark by looking through the eyepiece and sighting the cross hairs.

6. Directing the helper to extend the 8 foot measuring stick, find a corner post to mark a level line with the pencil. This is accomplished by having the base of the measuring stick placed either on the ground or the foundation and finding the height reading through the eyepiece. The cross hairs of the transit will provide that measurement by focusing the eyepiece and adjusting the focal screw like a telescope. You can now place the measuring stick around the area to be leveled.

7. Understand that the difference of the ground will be noted by the elevation measurements you see through the eyepiece. In other words, if the base measurement is 72 inches or 6 feet and the next reading through the transit is 75 inches or 6 feet 3 inches that means the ground is lower in that area by 3 inches. Conversely, the ground will be higher if the reading is less than 6 feet, such as 5 foot 10 inches then there is a rise of 2 inches.

Tips & Warnings

• You can record a basic shape on a piece of paper and note the measuring stick readings on the paper for interpreting the ground level difference. You can also place a marker flag below the center of the tripod to find your "benchmark" position of the transit tripod for future references.