How to use a plumb bob pdf

Fix the metal cylinder on the lathe machine such that one flat end of the piece is facing the drill bit. Turn on the lathe machine. Drill a hole into the cylindrical piece. Widen and deepen the hole as per your requirement. The hole should be such that a little over half the bolt should be screwed in. Turn off the lathe machine and clean off the hole and remove any metal shavings.

Screw in the screw bolt using a screwdriver. Take a hand axe saw and cut off the head of the screw bolt such that about 0. Sand off the screw bolt to smoothness. This step can also be done using a sander without using the lathe machine. Turn off the lathe machine. Screw-in the conical metal piece to the screw bolts such that the pointed end is on the outside.

Make sure it is tightened. Turn on the lathe machine Turn and sand off the conical metal piece if required. Turn the cylindrical metal piece and the conical piece for a smooth finish. Make the pointed end sharp. Take out the piece and attach the drill bit attached to the lathe machine. Drill an end to end hole into the piece. Sand off the ends and clean off the metal shavings. Remove the finished piece.

Take a piece of nylon thread. Using a lighter, burn one end of the thread such that it becomes soft and can be shaped. Press down quickly on the softened portion of the thread to make it into a conical shape. Push in the conical end of the thread into the conical metal piece from the flat end. Masons prefer nylon because it stands up better over time to the dampness that comes with the trade. At one end of the string the weight is affixed. Precisely machined and balanced bobs have pointed tips, and can be made of brass, steel, or other materials, including plastic.

How to Use a Plumb Bob To use the tool, the string is fixed at the point to be plumbed. The weight, or bob, is then allowed to swing freely; when it stops, the point of the bob is precisely below the point at which the string is fixed above. Note that the line must be hanging free to get an accurate reading.

The plumb bob is useful in establishing vertical for a wall in construction or a doorjamb when hanging a door. A spirit level will also accomplish those tasks, but some jobs are much more easily done using the tool.

For example, you can locate fixtures or decorations in relation to an object or surface below or above using the plumb line. Once it is hung and still, the top and bottom points can be marked and used as guides.

The plumb bob is useful in establishing vertical for a wall in construction or a doorjamb when hanging a door. A spirit level will also accomplish those tasks, but some jobs are much more easily done using the tool. For example, you can locate fixtures or decorations in relation to an object or surface below or above using the plumb line. Once it is hung and still, the top and bottom points can be marked and used as guides.

The plumb line in one place can be used to sight an object in another — a pipe, for example — for plumb. Surveyors sometimes use plumb bobs for lining up points or transferring them. Excavation and foundation contractors rely upon the plumb line, and constructing a chimney the tool can indicate whether a flue is running true vertical or veering off plumb. Some bobs have pointed tips that can be bent by repeated use or abuse; if the point on yours is bent or out of alignment, replace it.

Plumb bobs may weigh as little as an ounce or as much as several pounds, depending upon the application. For most home toolboxes, I recommend having a single bob that weighs a few ounces.