QA

How To Read A Bubble Level

What do the lines on a bubble level mean?

Many spirit (also called bubble) level vials have two sets of lines. But when it touches one of the outer lines, it means the level is pitched at a 2-percent grade (about ¼ inch per foot of run), the slope required for waste lines, sidewalks, and rain gutters to drain properly.

What is 1/4 bubble on a level?

A 1/4 of a bubble on any level is 1/4″ per foot slope.1/8″ bubble is 1/8″ slope ect.. The line , left or right of the bubble, is not the same measurement on all levels.

What does a bubble level measure?

A spirit level, bubble level, or simply a level, is an instrument designed to indicate whether a surface is horizontal (level) or vertical (plumb).

What are the 3 bubbles on a level?

Some levels also have a third vial which allows you to find a 45 degree angle too. On each vial there are two marks that are spaced apart. When the bubble sits between them it indicates a horizontal or vertical level (or 45 degree if you are using the third diagonal vial).

What bubbles for a level?

The bubble in the center of every vial (if there is more than one) should be centered between the two level indication line marks. If the bubble is centered, the surface you are checking is level. If the bubble is off center, then your surface will be rising up to the side that the bubble is higher on.

How do you read a level slope?

Slope can be calculated as a percentage which is calculated in much the same way as the gradient. Convert the rise and run to the same units and then divide the rise by the run. Multiply this number by 100 and you have the percentage slope. For instance, 3″ rise divided by 36″ run = .

How do I check my leveling?

You can perform a similar test to check that your level gives you an accurate plumb reading. Hold the level up against a door frame, take note of the bubble location, then flip it vertically 180 degrees and check for plumb again. If the bubble stays in the same location, your level is accurate.

How accurate is a bubble level?

Accuracy – a bubble level is only as good as its ability to give you a truly level measurement. We prefer to use levels with 0.0005″/1″ accuracy or better. On a 48″ level, that gives us a maximum error of +/- 0.024″, or 3/125″.

What is a 2 foot level used for?

Homeowners and renters usually prefer levels that are 2-foot or shorter in length. A 6-inch level is useful for leveling smaller picture frames on walls. Small 2-inch square levels are used in recreational vehicles to ensure that major appliances are level before operation.

What are the different types of levels?

These levels are further categorized into several other types. Spirit/Bubble Levels. A spirit or bubble level consists of a small glass tube filled with alcohol and a little air bubble sealed inside. Water Levels. Optical Levels. Laser Levels. Carpenter’s Level. Mason’s Level. Surveyor’s Leveling Instrument. Line Level.

What are the best levels?

10 Best Levels – Reviews Stabila Aluminum Box Beam Level Set. Stanley Non-Magnetic Level. Empire EM81. Sola MM Magnetic Torpedo Level. Klein Tools 935RBLT Lighted Torpedo Level. Skil LV941901 Digital Level. M-D Building Products 92288 SmartTool Electronic Level. DigiPas DWL80E Pocket Size Digital Level.

How do you measure the slope of a bubble level?

Take note of where the bubble is inside the spirit tube. If it’s centered between the lines on the tube, your object is level. If the bubble is to the right of the lines, your object slopes downward right-to-left. If the bubble is to the left of the lines, your object slopes downward left-to-right.

Why are there 2 bubbles on my level?

A5: Wood levels typically have a dual-vial system of curved vials. There are two vials so the level will work on when lying on either its top or bottom edges. Since air bubbles seek the highest point, the bottom vial (the one shaped like a rainbow) will be the working vial.

What angle is a 2% slope?

Table of Common Slopes in Architecture Degrees Gradient Percent 1° 1 : 57.29 1.7% 1.15° 1 : 50 2% 1.19° 1 : 48 2.08% 2.86° 1 : 20 5%.

What is a 1% slope?

1% as a decimal is 0.01 and hence the slope is 0.01. That means for a run of pipe of a certain length the rise must be 0.01 times the length. Thus for you example, since the length of the run is 80 feet which is 80 × 12 = 960 inches the rise must be 0.01 × 960 = 9.6 inches.

What is a 1 48 slope in inches?

For the cross slope of an accessible route the maximum slope allowed is 1:48. The distance from the bottom edge of the level to the surface should be no more than ½ inch (. 5:24 = 1:48).

How many inches per foot is a 2% slope?

How many inches per foot is a 2% grade? 100 foot divided by 12 inches increase by 2% = 12.24 inches ,which is just a bit short of 1/4″ increase every foot of the 100 feet.

How steep is a 10 percent grade?

How Steep Is A 10 Percent Grade 7.13 ° 1: 8 12.5% 10 ° 1: 5.67 17.6% 14.04 ° 1: 4 25% 15 ° 1: 3.73 26. 8%.

How do you read a leveling instrument?

To read the staff, take the number shown below the reticle. Count the number of whole 10mm increments between the whole number and the reticle. Then estimate the number of mm between the last whole 10mm block and the centre of the reticle. The diagram above shows 4 readings:- 1.950, 2.000, 2.035 and 2.087.

How do you read staff levels?

The staff reading is the reading on the staff at which the horizontal hair appears to cut the staff. A staff reading consists of 4 digits. The first digit represents the whole number of meters, the second digit represents decimeters, and the third, and fourth digits represent millimeters.

How do I know if my spirit level is accurate?

Q: How do I check the accuracy of a spirit level? Place the level on a flat surface. Make two marks: One at an end of the level. Look at the vial and take a reading of the bubble’s position. Rotate the level 180° end-to-end and align the level with your marks. Take a second reading.