3pcs 3-12mm 4-12mm 4-20mm HSS Straight Groove Step Drill Bit Set
Package & Shipping:
- Free shipping all over the world
- 1 x 3 PC HSS step drill
- To Korea, Japan : it take about 7-10 days
- To USA, CA, Spain, France, Poland, Belgium, Portugal, United Kingdom, Germany, Italy and Netherlands: it take about 12 - 20days
- To other European countries and Ukraine,Belarus,Russian Federation: it take about 15-30 days
- To other countries: it take about 20-35 days
- Products for automotive processing, aerospace, sheet metal processing
- Installation and maintenance of electrical and other industries
- High-altitude operations with hand drills and other tools
- The unique step structure, a variety of standard size drill carve aperture, a box arrived on a ladder drill bit.
- Without the use of center punch, easy to break, a step drill specifications apply.
- Deburring, chamfering, expanding the oval hole.
- Small sway, without leading to use a center punch can carve out a nice aperture.
- Surface treatment: Titanium.
- 5 step drill bit: 4-12mm (4mm, 6mm, 8mm, 10mm, 12mm)
- 9 step drill bit: 4-20mm (4mm, 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm)
- 10 step drill bit: 3-12mm (3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm)
What is HSS Drill Bit?
High-speed steel (HSS or HS) is a subset of tool steels, commonly used as cutting tool material (High-speed steel - Wikipedia).
It is often used in power-saw blades and drill bits. It is superior to the older high-carbon steel tools used extensively through the 1940s in that it can withstand higher temperatures without losing its temper (hardness). This property allows HSS to cut faster than high carbon steel, hence the name high-speed steel. At room temperature, in their generally recommended heat treatment, HSS grades generally display high hardness (above Rockwell hardness 60) and abrasion resistance (generally linked to tungsten and vanadium content often used in HSS) compared with common carbon and tool steels.
Step Drill Bit
A step bit is designed primarily for drilling in thin metal, up to 1/4 inch, but will work with wood. The stepped design allows you to use a single bit to drill holes with different diameters. Often the diameter of each step is etched into the metal drill bit. You can also use this type of bit to deburr holes, clearing away waste material.
Drill Bit Materials and Finishes
The materials from which bits are manufactured and the finishes applied to them play a significant role in the life and performance of the bit. Common materials and finishes include:
- High-speed steel (HSS) drill bits can drill wood, fiberglass, polyvinyl chloride (PVC) and soft metals such as aluminum.
- Cobalt drill bits are extremely hard and dissipate heat quickly. They're mostly used for boring in aluminum and tough metals such as stainless steel.
- Black oxide-coated HSS drill bits have a finish designed to help resist corrosion and increase durability. They last longer than basic HSS bits and work well on a variety of materials including metal, hardwood, softwood, PVC and fiberglass.
- Titanium-coated HSS drill bits produce less friction. They're tougher than basic HSS bits and stay sharp longer. They work for drilling wood, metal, fiberglass and PVC.
- Carbide-tipped drill bits stay sharp much longer than steel, HSS or titanium bits. They're effective for drilling tile and masonry.