Heading for improvement: Drilling Performance

END USER: Precision 1 Machine Inc., (702) 301-6419.
CHALLENGE: Drill holes in 304 stainless steel used for header plates.
SOLUTION: An HSS drill.
SOLUTION PROVIDER: OSG Tap & Die Inc., (800) 837-2223, www.osgtool.com

Bolt-on exhaust headers improve engine performance by making it easier for the engine to push exhaust gases out of the cylinders. Most headers for naturally aspirated engines are made of mild steel. Turbocharged engines create more heat and therefore the headers are often made of stainless steel. Stainless is the next step up from mild steel in both heat resistance and durability.

Recently, header plate manufacturer Precision 1 Machine, Las Vegas, had to drill 10mm-dia. through-holes in ½ “-thick 304 stainless steel. The part was approximately 16 ” long × 2¾ ” wide and required 12 holes. Nick Robertson, president and owner of the one-man job shop, had been applying standard cobalt drills but was experiencing poor tool life and encountered an abnormal sound during the operation.

“I’d get maybe one or two holes and then the drill would break,” Robertson said. “I tried about 20 different ways to drill the hole and probably went through at least 10 to 15 various drills, but they kept breaking.”

As for the abnormal sound, “if the feeds and speeds weren’t exactly correct, the cutting edges would be destroyed within the first hole. As soon as that happened, the drill would start screeching,” Robertson added.

As a temporary solution to get some parts out, Robertson contracted a local waterjet shop to produce the holes at $40 per part. Robertson was not only losing money by using an outside vendor, he also had to extend his lead time.

Courtesy of OSG