Published 11/26/2019

Drilling and Chamfering Tool Solves Machine Shop's Vexing Problem

An oil & gas part with a lot of holes required that Utex use two different tools to ensure burr-free inner and outer diameters. With Heule’s Vex-S tool, the shop realized time savings per cycle of an entire minute by performing drilling and chamfering in a single step.

Edited by: Jedd Cole

Former Production Editor, Modern Machine Shop

One Cutting Tool, Two Jobs

According to Brian Boles, a programmer at Utex, the manufacturer previously used a highspeed steel drill followed by a separate chamfer tool for making the holes in the seal cap application. Now, the shop uses the Vex-S tool, which combines a solid carbide drill with Heule's Snap chamfering system to drill and chamfer the front and back of the part in one step. This new setup eliminates a tool change and second operation, shaving a minute off the cycle time for each part.

With the Vex-S, a solid carbide drill is combined with Heule’s Snap chamfering system to drill and chamfer the front and back of the part in one step. This eliminated a tool change and second operation for Utex. In addition to shortening production time, the tool saves on maintenance time as well. Utex personnel estimate that the solid carbide drill tip lasts longer than comparable drill bits, saying that with adequate cooling, the Vex-S works for a month without changing inserts.

That average time savings adds up quickly. Utex produces 200 to 400 parts in a 24-hour timeframe, drilling and chamfering 2,400 to 5,000 holes a day. With a time savings of a minute per part, the shop saves up to six hours worth of production time through efficiency gains. With the time saved, Utex has been able to manufacture even more seal caps, which has helped the shop adapt to high demand for the assembled finished product.

Another common waste of production time was the need to change broken inserts. The solid carbide of the Vex-S’s drill tip lasts longer, and replacement enables the shop to swap blades without using tools or presetting between drill changes. With adequate coolant, Mr. Boles estimates the Vex-S can go for over a month without having to change inserts.

Along with the increased productivity, another noticeable bonus is the resulting cost savings per part. Producing the seal cap with the Vex-S eliminates the need for the chamfering tool entirely.

Utex uses the Vex-S tools on Okuma lathes. Previously, the shop used high-speed steel drills to make the holes plus a separate chamfering tool to clean up the inner and outer diameters.

How the Tool Works

The Vex tool uses Heule’s Snap chamfering blade, which deburrs and chamfers the bore edges without reversing the spindle, dwelling or indexing the part. As the rotating Snap blade is fed into the hole, the front cutting edge deburrs the top of the hole by cutting a 45-degree chamfer. When the blade is forced into the part, the blade slides back in the blade window, and only the ground sliding surface touches the hole, protecting it from damage while the tool is fed through the part. This prevents the need for stopping or reversing the spindle. When the blade extends beyond the back of the part, a coiled spring pushes it back out into cutting position. As the blade is withdrawn, it deburrs the back edge. When the blade is again in the blade window, the tool can be rapid fed out and on to the next hole, increasing production efficiency.