Having great equipment is crucial to our ability to deliver against the demanding standards of today’s manufacturers and the parts they need. A crucial component of our toolset is the indexable drill, which is simply a drill designed to accept inserts that clamp into a tool body. In this article, we’ll talk about when to use an indexable drill and take a deeper look at its reliability.

An indexable drill is recommended if you are drilling a hole bigger than 19 mm. It allows the operator to drill faster and more efficiently, and that’s the name of the game.

Plus, an indexable drill has a variety of uses. It can be used as a core drill, like a boring bar—the original hole can be completed using this drill, and then you can step it over as if it was a boring bar—or used to finish chamfers and radii.

Most indexable drills we use at Rathburn have two inserts, an inboard insert and an outboard insert. To use the inserts correctly in the drill, use a tough grade for the inboard insert because it does not see a lot of speed. For the outboard insert, use a hard grade that can handle the higher speeds. One way to avoid confusing the two inserts is to use a square outboard insert and a trigon inboard insert. The shapes indicate type of grades and are less likely for operators to confuse.

Through the tool coolant is not needed when using the drill at 35 mm depth or less. For deeper holes, it is best for coolant to run through the drill. If a flat bottom hole needs to be drilled, we recommend using indexable drill inserts specifically designed for that task. Above all else, we suggest never pecking with an indexable drill. Pecking will quickly destroy your drill. Instead, keep the insert in the cut or you will run the risk of thermal shocking the tool and cracking it.

An indexable drill is a very reliable tool, if you take good care of it. At Rathburn, we’ve drilled SAE 8620, 35 mm deep with 600 pieces for the outboard insert and 1,200 pieces for the inboard insert before requiring an insert change.  Follow the manufacturers’ recommendations for speeds and feeds to maximize your tool life.

About Rathburn Tool & Manufacturing

Established in 1983, Rathburn Tool & Manufacturing delivers precision-machined, manufacturable solutions made possible by a combination of technology and experienced teams for companies that need their products and equipment to work well every time.

Our shop floor is filled with a collection of traditional, automatic, and robotic machining tools that enable us to deliver the highest quality parts to our customers. Our skilled engineers and operators make the magic happen every day. To find out more about the tools we use, please reach out to us at info@rathburnmachining.com.