This helps ensure the components manufactured on the machines can meet the required tolerances and repeatability. The main spindle is generally hollow to allow long bars to extend through to the working of lathe machine pdf area.
This reduces preparation and waste of material. Later machines use a gear box driven by a dedicated electric motor. A fully ‘geared head’ allows the operator to select suitable speeds entirely through the gearbox. Types of beds include inverted “V” beds, flat beds, and combination “V” and flat beds. V” and combination beds are used for precision and light duty work, while flat beds are used for heavy duty work. There is no need to make the machine exactly horizontal, but it must be entirely untwisted to achieve accurate cutting geometry.
A precision level is a useful tool for identifying and removing any twist. It is advisable also to use such a level along the bed to detect bending, in the case of a lathe with more than four mounting points. In both instances the level is used as a comparator rather than an absolute reference. This provides a constant relationship between the number of turns the spindle makes, to the number of turns the leadscrew makes.