that don’t just improve the life of the tap but the quality of the threads, too.
“Most companies would tell you it’s accurate enough to hold the tap in a collet chuck in a machine that is brand new, but over time, the ballscrews get a little end play in them so there’s not as much accuracy,” BIG Kaiser’s Burley said. In rigid tapping, one should feed the exact pitch per revolution of the tap. Going in isn’t so much the problem as
A Growing Range of Tap Holders Meanwhile, Emuge (West Boylston, MA), a leader in thread cutting technology, which also says it was the first to offer SSY tap holders, reports that it has the widest range of tap holders and continues to expand its lineup. Last year, Emuge introduced new modular MQL Softsyn- chro tap holders for machines with synchronous spindles. The new Softsynchro MQL modular system makes it pos- sible for the same toolholder body to be used for minimal quality lubricant or HSK coolant applica- tions. Emuge MQL Softsynchro modular tools can also be custom-built from standard components, depending on the tap size, MQL configuration and application. The new MQL modular system features a pressurized MQL delivery system supplying a sealed air system that equalizes the pressure within the MQL tube and collet adaptation throughout the entire holder. With this system, pressure is the same on the inside of the tube and outside of the MQL delivery system preventing any leaks within the MQL holder.
Designed for machines with synchronous spindles, the Emuge Softs- ynchro® HD and MQL Modular System makes it possible for the same toolholder body to be used for minimal quantity lubricant (MQL) or HSK coolant applications.
reversing and getting the tap out of the hole exactly the way it went in. Complete synchronization is a must to get a clean thread and protect the integrity of the tap.
Axial mismatch between the feed of the machine and the feed of the tap can leave behind threads with burrs and wear the taps unnecessarily because of extra load on them. A collet chuck is not designed to compensate for the mis- feed the way a tapping holder is with built-in elastic compo- nents that compensate with tension and compression. “It’s an overlooked process improvement and most customers don’t know what they could be missing,” Burley said. In fact, the tap holding area has been rife with competition in recent years, with a lot of new offerings and designs. BIG Kaiser has expanded its Mega Synchro line of tapping holders with the MGT36 at the larger end and MGT3 on the smaller end of its lineup. “Most of our customers see a huge increase in tap life,”Burley said.
The modular toolholder can also be supplied with a spring-loaded tube, the preferred method in MQL applications. The modular system for the HD units provides coolant-thru capability up to 50 bar in the high-pressure SSY units. And these SSY holders have the option of adding an adjusting screw, giving the ability to preset the length of the tap.
The modular system also employs a new Heli-Coil mecha- nism designed to reduce the force that occurs when tighten- ing the collet nut. When tightening the collet nut with the tap fixed against the adjusting screw, there typically is some movement that can damage the tap or adjusting screw.
“Most companies would tell you it’s accurate enough to hold the tap in a collet chuck in a machine that is brand new, but over time, the ballscrews get a little end play in them so there’s not as much accuracy.”
The axial movement of the collet can be 0.08 to 0.3 mm, with forces of 800–5000 N. The Heli-Coil mechanism compensates for this axial movement, preventing unwanted