Sunnen's new HTE honing system, the company's most cost-effective small-diameter hone, produces ideal bore geometry and surface finish, while eliminating problems from bad tool-to-part alignment and excessive feedrates that cause tool breaks and scrap parts. The new tube hone's one-piece base maintains excellent tool/part alignment, and a special feature of the feed system provides maximum protection against tool overloading. Tool specific force limits and run settings are stored in the Windows-based touch-screen control. A unique feed system senses tight sections in the part and corrects them automatically. The HTE handles parts up to 60" (1524 mm) long and has an ID range of 0.160-0.750" (4-19 mm), making it ideal for improving the finish and performance of safety valves in oil field parts, tubing for nuclear energy fuel rods, raw materials for pharmaceutical stents and gun barrels as small as .17 caliber, among others. "The one-piece base not only improves the machine's performance, it makes it more affordable," said Dennis Westhoff, business development manager for Sunnen. "The spindle power is also reduced on the low end, making the machine extremely sensitive to tool overloads in long, narrow bores." The HTE's servo-controlled, variable speed spindle (5-2100 RPM) and stroke motors (1-98 ft/min, 1-30 m/min) produce superior stock removal rates in Inconel, 410 stainless steel, zirconium and titanium alloys. The HTE can utilize a variety of Sunnen tooling types including MMT, LFT-DX and GH tools. Three fixturing options are available: a manual chuck, a pneumatic chuck, or a V-type chain vise for parts with OD's up to 6" (150 mm). A travelling steady rest is standard. An optional guide pot automatically guides the honing tool straight into the bore without operator assistance. Standard, non-CE guarding includes easily removable covers for each end of the honed part, while optional CE guarding includes a light curtain and wire mesh enclosure. The Swiss-designed machine is built in the U.S.