Article From: 11/15/2002 Production MachiningA new line of electropneumatic drill units cuts holemaking costs while maintaining standards for performance, quality and tool life established by standard Selfeeder drilling machines, according to the company. Identified as the "G.bal" series in the expanding lineup of Selfeeder drill units, the series was named for its universal appeal and adaptability to virtually any application, replacing hand drills, radial drills, pneumatics and to other automated drilling operations, the company says. The G.bal Selfeeders are offered in more than 30 models with power rated at 0.33, 0.50, 0.75, 1.0 and 1.5 hp. Standard stroke lengths are 3.15" and 3.94"; long 5.91" and 7.87" stroke lengths are available. Maximum speeds range from 12,000 rpm for the 0.33 hp drill unit to 7,300 rpm for the high-torque 1.5 hp G.bal unit. The 1.5 hp G.bal unit produces 720 Ibs thrust. TIR (Total Indicated Readout) accuracy is 0.0006". Repeatability is ±0.0008". Numerous design features went into the new G.bal units. The two-piece spline system was replaced with a one-piece drive shaft. The elimination of a spline-shaft system reduces the length of the drill, creates a smoother rotation performance and reduces the noise level of the operating drill unit. With flexibility to mount the motor in front or back, or at 90 degrees to either side of the unit, the G.B. can be installed in the tightest and most demanding space requirements. The G.B. was designed with an integral foot mount-type body for precise, simplistic alignment. Among the other standard features is a twin guide-bar system for stability and accurate drilling conditions, high-output standard motors, multispindle head adaptability and more. An optional feature is a through-the-tool coolant capability. The addition of an operational signal kit will detect home position and maximum drill depth position and provide plc interface signals required for sequencing other operations and equipment.