The Swiss Lathe
The Swiss lathes are also known as Swiss screw machines, Swiss automatic lathes or Swiss turning centers. A Swiss lathe differs from a traditional lathe in that the collet that holds the bar stock is not directly exposed to the tooling, which adds a number of advantages over a traditional lathe.
The advantage the Swiss lathe has, is due to its use of a guide bushing which offers extra support to the bar stock when it is turned. The guide bushing is located very close to where the turning is being done therefore being able to hold better tolerance.
Swiss lathes have the ability to turn small-diameter parts and also turn parts that have a larger length-to-diameter ratio. Chatter of tooling is also minimized due to the guide bushing. Traditional lathes have a fixed head-stock where as in Swiss lathes the head-stock moves, which means the bar stock will feed through the collet in the area of the head-stock that it will clamp onto.
The bar stock is then fed through the guide bushing in the machining area. The head-stock then moves in a back and forth motion in Z while taking the bar stock with it. Turning tools are located on a gang which slides to turning position, at that point the bar stock will make contact in close proximity to the guide bushing and the bars movement acts as the feed required for turning. The gang slides carry all single point machining tools and some live tooling. They also have secondary tooling to achieve back turning.