TopThread™ Threading Selection Guide Step 1 • Select Threading Method and Hand of Tooling Required Information: • External/internal operation. L R L R L R • Spindle rotation/hand of thread. • Feed direction. hand of thread hand of toolholder hand of insert Feed direction toward the chuck • RECOMMENDED L RL L R R L L RR L R external left-hand thread external right-hand thread internal left-hand thread internal right-hand thread Feed direction away from the chuck L L L R R L L R RR L R external right-hand thread external left-hand thread internal right-hand thread internal left-hand thread Step 2 • Select Holder from Catalogue Page The insert size must match the gage insert size of your toolholder selection: Select the appropriate holder for the insert size and hand: Required Information: • External/internal operation. • Minimum bore diameter (for internal operations). • Hand of tool. • Insert size (gage insert). catalogue gage number insert NSR-163D N.3R NOTE: Optimise your threading operation by using the proper infeed method and the recommended infeed values. NSR-164D N.4R See the Technical section on pages F79–F101 of this catalogue. NOTE: TopThread toolholders and boring bars are listed with a gage insert to For internal threading, minimum bore varies depending on thread type. indicate the size and hand required. They are compatible with See page F92 for details. both grooving and threading inserts of the same size. F6 widia.com