How to measure the helix angle of a twist drill?

Hey there! As a twist drill supplier, I've been in the drill game for quite a while. One of the key things that often comes up when dealing with twist drills is measuring the helix angle. So, in this blog, I'm gonna walk you through how to measure the helix angle of a twist drill.

First off, let's talk a bit about what the helix angle is and why it matters. The helix angle of a twist drill is the angle formed by the helical flutes of the drill bit. It plays a crucial role in how the drill bit performs. A larger helix angle is great for drilling softer materials because it allows for better chip evacuation. On the other hand, a smaller helix angle is more suitable for harder materials as it provides more strength and stability.

Now, let's get into the nitty - gritty of measuring the helix angle. There are a few different methods you can use, and I'll go over each one.

Method 1: Using a Helix Angle Gauge

This is probably the simplest and most straightforward way. A helix angle gauge is a specialized tool designed specifically for measuring the helix angle of drill bits. To use it, you just place the gauge on the flute of the twist drill. Make sure it's properly aligned with the helix of the flute. Then, read the angle value directly from the gauge. It's as easy as that!

But where can you get a helix angle gauge? You can find them at most hardware stores or online. They're not too expensive, and if you're in the business of dealing with twist drills regularly, it's definitely a worthy investment.

Method 2: Mathematical Calculation

If you don't have a helix angle gauge handy, you can also calculate the helix angle using some basic math. Here's how it works.

First, you need to measure two things: the lead of the helix and the circumference of the drill bit at the point where you want to measure the angle.

The lead of the helix is the distance the drill bit would advance in one complete turn if it were screwed into a material like a screw. To measure the lead, you can mark a point on the flute of the drill bit and then rotate the drill bit one full turn. Measure the distance that the marked point has moved along the axis of the drill bit. That's your lead.

The circumference of the drill bit can be calculated using the formula (C=\pi d), where (d) is the diameter of the drill bit at the measurement point.

Once you have the lead ((L)) and the circumference ((C)), you can calculate the helix angle ((\theta)) using the formula (\tan\theta=\frac{L}{C}). Then, to find the actual angle, you just take the inverse tangent (also known as arctangent) of (\frac{L}{C}). You can use a scientific calculator to do this. For example, if you find that (\frac{L}{C} = 0.5), then (\theta=\arctan(0.5)\approx26.57^{\circ})

Method 3: Using a Protractor and a Template

This method is a bit more DIY. You'll need a protractor and a template. First, make a template of the drill bit's cross - section. You can do this by tracing the drill bit on a piece of paper. Then, place the template on a flat surface.

Next, take the protractor and align it with the helix of the flute on the template. Try to estimate the angle as accurately as possible. This method is not as precise as using a helix angle gauge or mathematical calculation, but it can give you a rough idea of the helix angle, especially if you're in a pinch.

Now, I'd like to mention some of the twist drills we offer as a supplier. We have a great 12pcs Wooden Box 1/2 Shank Sliver and Deming Drill Set. This set is perfect for a variety of drilling tasks. The drills are well - made and have the right helix angles for different materials.

Another popular product is our Fully Ground HSS Straight Shank Twist Drill Bit. These drill bits are made from high - speed steel (HSS), which means they can handle high - speed drilling and are very durable. The helix angles are carefully engineered to ensure optimal performance.

And if you're looking for a set with a bit more variety, our 13Pcs Hex Shank Straight Shank Twist Drill Bit Set is a great choice. The hex shank design makes it easy to use with a variety of drill chucks.

As a twist drill supplier, we understand the importance of getting the helix angle right. It can make a huge difference in the performance of the drill bit. Whether you're a professional contractor, a DIY enthusiast, or someone in the manufacturing industry, having the right twist drill with the appropriate helix angle is essential.

If you're interested in our products or have any questions about twist drills and helix angles, don't hesitate to reach out. We're always here to help you make the right choice for your drilling needs. We can offer you expert advice on which drill bit with the right helix angle is best for your specific application.

In conclusion, measuring the helix angle of a twist drill is not as complicated as it might seem at first. You can use a helix angle gauge, do some math, or use a DIY method with a protractor and template. And if you're in the market for high - quality twist drills, we've got you covered.

References

• "Machinery's Handbook", Industrial Press Inc.
• Various technical manuals from drill bit manufacturers.