What Are Spade and Indexable Drills?

Drilling refers to a cutting process where a drill bit is used to cut a circular hole in material, and it is a common practice for establishing assemblies and accessing areas underneath a surface. Depending on the application in question, the operating environment, the material being drilled into, and other various factors, there are numerous types of drills and drill bits that one may take advantage of. Spade drills and indexable drill inserts are both common options for many different operations, and the two are often compared to one another in terms of their design and capabilities. To help you determine which type of bit or tool is best fit for your individual needs, we will provide a brief overview of each and how they work. 

Spade drills feature a bit in which a flat-end cutting blade with two cutting lips is used. With this design, spade drill inserts can cut deep into surfaces or make holes with larger diameters. With the ability to quickly swap out inserts as needed, spade drills ensure a quick set-up process for rapid use. By changing the drill bit, a user can create various sized holes with ease, all without having to change what tool they are using. If one is involved in horizontal machining center applications, the straight or helical flue spade drill is a good option for maximizing overall chip evacuation.

On the other hand, indexable drills are known for being more complex than spade drills in terms of their design, featuring two inserts. The inner indexable drill insert is used to cut the inner portion of the intended hole, while the outer insert establishes the final hole diameter while cutting out the portion. With higher penetration rates, high performance indexable drills ensure a reduction in machine cycle times. This is coupled with their ability to reduce chip friction, ensuring chip control during the drilling process. While indexable drills are primarily relied on for standard drilling applications, they may also serve for boring, facing, and turning as required. Similar to spade drills, indexable drills feature various inserts, those of which are the straight flute and trigon variation. 

All drill bits may vary in their tool material and coatings, and choosing the right option for your individual needs is very important. Generally, the most common tool materials are high speed steel, cobalt, and solid carbide. While high speed steel is a general option that is known for its low price point, materials such as solid carbide excel in high-performance applications with their ample wear resistance, rigidity, and accuracy. Coatings are similar, and the common options are titanium nitride, titanium carbonitride, titanium aluminum nitride, and FIREX. For high temperatures and abrasive environments, the titanium aluminum nitride coating is best, while a coating such as FIREX ensures ample hardness and heat resistance. 

Whether you are in the market for a spade drill or an indexable drill insert, we at ASAP Industrials are ready to fulfill all your part needs with ample time and cost savings. Take the time to explore our massive set of offerings as you see fit, and our RFQ service will allow you to rapidly request quotes for your comparisons with ease. Fully dedicated to quality, we go above and beyond standard industry expectations to bring customers the best items and services in the industry. As a result of our consistent efforts, we proudly conduct operations with AS9120B, ISO 9001:2015, and FAA AC 00-56B accreditation. Get in contact with one of our representatives at your earliest convenience, and see how ASAP Industrials can serve as your strategic sourcing partner for all your various operational requirements.

1. jacob miller
2. Posted on April 13, 2022
machinery