Boring

One of the challenges when boring workpiece materials susceptible to workhardening is recognizing whether the prebored hole is already workhardened.

Just in time (JIT) manufacturing, by nature, increases setups and shrinks batch sizes. This puts shops in a bind, because more setups and smaller batches are typically less profitable; but saying "no" to work can be even more painful. The burden to search out creative ways to reduce cycle and setup time in order to realize a profit falls to the shops that commonly perform JIT work and on the shops that can’t afford to turn it down when the opportunity arises.

Drilling, reaming and boring are the basic holemaking operations of machining. In simple terms, drilling creates a hole in a workpiece where there was no existing hole. Reaming and boring accurately enlarge holes that already exist.

END USER: General Products Corp., (260) 668-1475, www.general-products.com. SOLUTION PROVIDERS: Haggard & Stocking Associates Inc., (800) 622-4824, www.haggard-stocking.com; Rigibore Inc., (262) 363-3922, www.rigiboreinc.com. CHALLENGE: Overcome the concerns of applying fixed-pocket, brazed-PCD boring tools. SOLUTION: Special “one-shot” adjustable boring tools that accept replaceable PCD inserts.

A long boring tool can cause vibration, so deep holes can be deep trouble. But several strategies can minimize vibration.

Horizontal boring mills are behemoth in size and flexibility.

END USER: Machine Tech CNC, (780) 461-0890. CHALLENGE: Accurately bore 14 diameters deep and deeper. SOLUTION: Carbide-reinforced boring bars with built-in vibration damping. SOLUTION PROVER: Sandvik Coromant Co., (800) SANDVIK, www.sandvik.coromant.com/us

Adjustable finish boring heads allow for a range of diameters to be machined with one tool. Finish boring can take some time but achieves tight hole tolerance and fine surface finish requirements. And if a fine finish and tight tolerance are not required, rough boring might suffice.

Boring is a common hole finishing operation, but boring large-diameter holes is a bit of a niche market. “Depending on the industry, you may only find a handful of shops in some areas capable of doing this type of work,” said Ron West, global product manager for Kennametal Inc., Latrobe, Pa. “They have the larger equipment necessary to do this type of work on a regular basis.”

END USER: Antron Engineering and Machine Co. Inc., (877) 225-2362, www.antroneng.com. SOLUTION PROVIDER: Eltool Corp., (877) 435-8665, www.eltool.com. CHALLENGE: Mill a long, interrupted slot in a small-diameter bore. SOLUTION: A coolant-driven angle head.