Rotary Table
The Rotary table is part of the vital equipment that a machinist uses to produce different metalwork designs. The equipment achieves precise designs in metal works by enabling the designer drill and cut metal pieces at regular intervals along a fixed axis. The table can be used in tandem with index plates or dividing plates. The operator of such a table uses a rotary fixture to attach it firmly to the working surface.
The tables can be manually operated or could energy powered. Common characteristics between the two categories however are the solid base, from where the rotary fixture is fixed. The main use of the rotary fixture is to clamp the table firmly on to a working surface, while the table resembles a disc to which the working blades are attached. The table's rotation is controlled by a hand wheel (worm), which operates as part of the Rotary table. The diameter ratio between the table and the worm is usually in three categories: 90:1, 72:1 or 40:1. These ratios are easily divisible into 360 degrees, which makes it easier to make fitting indexing plates. Indexing plates contains preset holes, which can be adjusted to various degrees.
Usually, machinists mount the rotary tables on a flat or level surface, thus allowing the table to rotate around the vertical axis. Alternatively, the table can be mounted on its end on a 90-degree angle thus giving it a horizontal rotation. The rotary table has t-shaped slots that are rotated by the hand wheel thus accentuating the worm and the worm gear. When the machinist uses the proper setup, the table cuts complex curves, which would otherwise prove very difficult to cut with the ordinary metal cutters. The table is also able to execute round cuts, helixes and large holes easily. The powered tables are especially efficient because all they require is proper presets.
The different tables have varying speeds and can handle different load capacities. When purchasing one, one is advised to get information regarding the table's torque, accuracy, resolution and operational speed before buying. Other vital details that a potential buyer should consider include the bearing type of the table (radial or axial), the circuit circulation per phase, the number of phases the table rotates at, the forcer type and the repeatability of the arc per second.
The air bearing of the table is also an important consideration because it determines the pressure flow of the table during metal cutting process. This can also be gauged by the table's air gap. It is also important that one understands the axial and radial run-out. A table's capacity is determined by the outside diameter, the aperture diameter and the overall height of the rotor and the stator. Proper use of a rotary table includes ensuring that all safety measures are observed. This includes properly aligning a milling machine at the centre of the table and moving the machine to the desired radius and then making the desired cut. A manual rotary table would include calculating the tangent of the two straight lines and then locking the rotary clamps before making the cut.