Choosing the correct type of drill for plastic is essential to ensure that your holes are uniformly shaped, clean, and undamaged. Knowing the right way to drill holes in plastic will save you a lot of time and resources.
If you are in the process of figuring out what type of drill bit you need for drilling plastic, then to give you a quick idea, any of the following will work:
Dowel bits or Spur-Point Drill bits
Twist HSS (High Speed Steel) drill bits
Step Drill
For more information we suggest reading on, as there are some significant differences with these drill bits and particular points when you should and shouldn’t be using them.
Drill bit for plastic deep dive
Each drill bit is designed for different purposes. For example, drill bits for concrete are not the same as those for plastics.
The difference in drill bits is affected by a variety of factors. One of the significant differences between bits is their physical shape, materials, or geometry.
Dowel bits or Spur-point Drill bits
Drilling holes in plastic is best done with spur-point drill bits. Also known as dowel bits, they have a center point and two elevated spurs that help keep the bit straight. The point and angle in front of these bits guarantee smooth cutting and reduce the stress in front.
They are an excellent drill bit for plastic because they leave a clean-sided hole. They do not leave rough edges that can cause cracks. Spur point bits, which come in sizes ranging from 3 to 10mm, can be used for drilling both plastics and wood.
Twist HSS (High Speed Steel) Drill bits
A standard Twist HSS (High-Speed Steel) drill bit (often referred to as Jobber Drills) can be used for drilling acrylic or plastic. In addition, high-speed steel bits are commonly utilized as a general-purpose bit suitable for wood, soft metals, and plastics.
Twist drill bits are made of carbon steel strengthened with chromium and vanadium. When drilling plastic, it's best to use a twist drill that has been used at least once. This will eliminate any burrs and keep the drill from biting into the plastic.
Step Drill
A step drill is a cone-shaped drill with increasing diameters, often known as a stepped drill bit. They are usually made from steel, cobalt, or carbide-tipped. They are used for drilling holes in bronze, cast iron, and steel.
They can also be used for softer materials such as aluminum, wood, and plastic. For example, step bits are excellent for drilling holes in plastic or acrylic because they can create smooth-walled and straight hole sidewalls. The resulting hole is clean and free of burrs.
How to make a hole in plastic without cracking it
Drilling plastic might appear simple, but if you are not careful, you may end up with splinters and cracks. Unlike concrete and wood there are some clear differences when drilling plastic, such as the need to drill 1-2 mm larger than the screws, to allow for both contraction and thermal expansion.
When drilling plastic, it is critical to use a slower drill speed. This will keep the high speeds from causing tremendous friction, and therefore melting through the plastic. A slower pace will also enable the chips to exit the hole immediately—the greater the size of the hole, the slower the speed of the drill.
You can do the following steps when drilling plastics or acrylics to prevent this from cracking :
- Clamp the plastic tightly to a stable surface and use a spare piece of plywood underneath to support the portion of the plastic you are drilling.
- To keep the other parts of the plastic from cracking, place painter's tape to the area where you intend to drill.
- While drilling, apply a lubricant to remove unwanted debris and reduce heat, especially when drilling deeper holes. Lubricants such as WD40, canola oil, or even vegetable oil.
- During the drilling process, apply little but firm pressure to the drill.
- Pause or slow down to re-lubricate the drill to prevent it from overheating.
- Remove the painter's tape, and you'll have another precisely drilled hole.
Are you still looking for the right option when it comes to drill bits for plastic? If so, we suggest heading to one of our category pages on:
Step drill bits
Twist drill bits and Hss drill bits
If however, you feel you are still unsure, then don’t hesitate to reach out as one of our team will be on hand to offer their expert advice.
