Machines/Accessories/Controls

Let technology be your guide when selecting a CNC.

A look at the various types of CNC lathes available to shops contemplating stepping up from a manual machine. The pros and cons of the following lathes are discussed: combination, cutoff, slant-bed, twin-spindle and turn/mill. The author also touches on available options.

Part I: The author discusses how to maintain and repair machine tool spindles and what causes spindles to run out of round. Common sources of out-of-round spindles include loose bearings and improperly ground spacers. In-machine spindle repair is also discussed. Part II: There are three common ways to repair tapered toolholders: regrinding, replacing damaged material and chrome-plating. The author discusses each, along with its price, and gives advice about choosing an option.

DNC can mean either Direct Numeric Control or Distributed Numeric Control. Either way, a DNC links a shop's computers and machine tools and saves times. A DNC eliminates manual transcription of NC data, the downtime caused by shop personnel having to make programming entries and transporting part programs between engineering and their machines.

Author explains the different ways to upgrade a used machine tool. He also discusses what users should expect from the company that performs the retrofit, rebuild or remanufacturing job and how long the job should take.

Shop owners who operate multitask machines talk about the time and cost benefits of producing parts in a single chucking. They also discuss some of the problems they had when adopting the technology. Accompanying Articles focus on a multitask users group and machine that hard-turns and grinds.

A rotary table allows a 3-axis vertical machining center to machine in the
4th and 5th axes. The author explains the different types of rotary tables
that are available and discusses the advantages and disadvantages of each.

Guide bushings are used in difficult holemaking applications to ensure that the drill produces round straight holes. This article discusses the types of bushings commonly used and the materials they are made from. Guidelines for sizing bushings for a given operation are also supplied.

According to this article, the short-bar barfeeders that are on the market today are not plagued by the drawbacks that have become associated with barfeeding. The units load 5-foot bar stock into a lathe rather than the longer stock loaded by earlier units. This article describes how shops can use short-bar barfeeders to keep a lathe busy with a steady flow of work and still change from one bar diameter and part program to another easily and quickly.

This article looks at different machine tool components and their impact on the machine's ability to operate at high speeds and feeds. Components covered include motors, drives, bearings, spindle coolant mechanisms, toolholders and CNC.