"TRISTAR" Automatic Grooving Tool besides Catering to various Applications for Internal Grooving is specially deigned for Machining Grooves in Tube Sheet Holes to aid in Locking Rolled Tubes into Position during Tube Expansion. 
"TRISTAR" Automatic Grooving Tool incorporates the Proven and Accepted Principle of an eccentric Tool Holder turning on its own Axis.
As the Tool moves into the work piece / Tube Sheet, the pilot nose contacts the face of the work piece / Tube Sheet, the cutter is now in the position to cut. Continued movement of the Tool starts the feed stroke which actuates the cutter and feeds it readily into the work.
The location of cut is controlled by a Quick Lock Adjustable Collar, the depth of cuts is also controlled by a Quick Lock-stop Nut, which permits simple, fast and accurate adjustments.