Load More Tools On Your CNC Lathe's Turret
Most shops accept the tooling limitations of their CNC lathes as a fact of life-something that cannot be changed and something to get around. However, one shop took a fresh look at the problem and came up with a way to increase the number of rotary tools that a turret can accommodate.
How many times have you wished you could add just one or two more rotary tools on the turret of your CNC lathe? Probably the same number of times that you had to set up one or more additional machines for secondary operations because you could not machine the part complete in one setup on the lathe. Most shops accept the tooling limitations of their CNC lathes as a fact of life—something that cannot be changed and something to get around. However, one shop took a fresh look at the problem and came up with a way to increase the number of rotary tools that a turret can accommodate.
The development was born of necessity. Foxwood Machine, Inc., a job shop in Rowley, Massachusetts, was presented with an opportunity to produce a number of relatively simple parts in large quantities for an important customer. Problem was, most of the shop's CNC lathes had limited tooling capacity and were slow to index. Management was concerned that the parts would require secondary machining, which would increase their cost and prevent the shop from quoting competitive prices. The shop did not want to turn down what it knew would become significant business. It took a look at the limited tooling capacity and slowness of some of its CNC lathes and came up with the Turretgang, a toolholder that effectively doubles and triples the number of hole-making tools that the turret can accommodate at one time.
The Turretgang toolholder mounts in the OD toolholding locations on the turret. It permits up to three tools to be mounted in each turret location instead of only one, greatly increasing the number of tools that can be used on a given job. Without the toolholder, only one rotary tool can be installed in each turret tool position, and when the tool has completed its operation the turret must retract, index to the next turret tool position, and advance to the part—a process that can take several seconds on some lathes. With Turretgang, however, the user can perform as many as three hole-making operations—for example, center drilling, drilling and counterboring—from the same turret location, freeing up the other turret locations for still more hole-making operations.
The toolholder is aptly named, because it brings some of the advantages of gang tooling to CNC lathes with conventional turrets. Instead of indexing to present the next tool in the cutting sequence, the turret simply slides along the X axis, presenting the next tool in the toolholder to the work with the speed of a gang-tooled lathe. The significant reduction in tool-indexing times means corresponding reductions in part cycle times. According to the manufacturer, the user can expect cycle time savings of 0.5 to 2.5 seconds or more for each additional tool used per holder, depending on the age, size and movement distance of the CNC lathe involved.
Setup times can be reduced by leaving the toolholder in place on the turret and simply changing individual tools. Additionally, toolholders equipped with tools for a specific job can be stored and quickly installed for repeat orders.
All too often, a shop must run a job on the wrong machine because other, more appropriate machines are booked solid. The Turretgang toolholder improves a shop's production flexibility because it levels the capabilities of the shop's CNC lathes. Older lathes that might have been a poor choice for a particular job become much more productive because of the greater number of tools and faster tool indexing the toolholder provides.
The Turretgang handles most rotary tools: center drills, drills, reamers, taps and . . ."every round tool that you have," the manufacturer promises. The system is said to be ideal for machining parts 2 inches in diameter and smaller; however, larger parts can also be accommodated by installing only two tools in the toolholder instead of three. The toolholder is sold in two styles: one for channel-style turrets and another for block-style turrets. Standard toolholders are available for most popular CNC lathes. However, some lathe designs provide only enough clearance between the turret and sheet metal for a two-tool toolholder instead of the three-tool version.
Hard turning can be a cost effective alternative for shops looking to streamline part processing.
CNC Swiss-Type machines have more capability built in than ever before. Many of these capabilites can be accessed using attachments that increase the throughput of the machine tool, improve the quality of the work coming off the machine and reduce or eliminate the need for secondary operations even for very complex workpieces.
Hard turning isn’t hard to do. However, it does require an understanding of the process dynamics and a systematic approach to the tooling involved. This article looks at how proper preparation will deliver consistent, predictable hard-turning results.