Criteria for selecting steady rest for a lathe
Category : BLOG
Thanks to machining one can produce parts with high dimensional accuracy and an excellent level of surface finishing, as long as it is carried out using equipment with the right performance characteristics. When it comes to the lathes, not only the machine itself is important, but also the tools we use, as well as accessories that facilitate the desired precision, including the use of an appropriate steady or follow rest.
What is the role of the lathe steady rest?
Turning machining involves the removal of excess chips from the workpiece, which is put into rotation with a strictly set number of revolutions, using a lathe knife with an appropriately shaped cutting edge and moved along a carefully selected path with a properly set feed speed. During the entire process, the material is affected by forces related to the rotary motion itself, as well as the work of the turning knife, which can result in deviation from the axis of rotation in accordance with the direction of the feed, that is, sideways as well as upwards, which is a consequence of the resistance posed to the cutting edge by the structure being machined. In the case of workpieces of small size, most of the impacts of this kind are offset by stable seating in either the center or the chuck, and sometimes the combination of chuck and center. If, on the other hand, the workpiece lenght is much longer, and the rigidity of the clamping system and the material itself proves to be too small, vibrations will occur. The way to deal with this problem is to use a device called a lathe steady rest which provides an additional point of support, thereby increasing stability and minimizing the risk of vibrations leading to the appearance of machining inaccuracies.
What are the common types of rest used in the lathe?
Lathe supports come in two basic variants – fixed steady (steady rest) or movable (follow rest). Fixed supports are installed on the guides of the lathe bed, which makes it not change its position in relation to the workpiece, limiting the range of motion of the tool. This means that the fixture must be changed if the entire surface of the workpiece needs to be shaped. Movable supports – follow rests – are attached to the lathe slide, which makes it change its position during turning, maintaining a constant distance from the lathe knife. Steady and follow rest can be equipped with 3 or 4 axis positioning elements They are also made in hydraulic self-centering versions, which improves handling, automating the positioning process.
A wide range of tooling for machine tools can be found in the offer of the company MultiMasz POLAND. It offers not only the purchase of fixed and movable supports, but also vibration isolators, setting wedges and coolant lines, among others.