How to Extend Your Flex Shaft With a Shaft-to-Shaft Connector

Sometimes, the reach of your flex shaft just isn’t enough. That’s where a shaft-to-shaft connector comes in handy. With this simple tool, you can securely join two shafts together and extend your working length without compromising torque transfer.

How It Works

The process is straightforward:

1. Insert one shaft into each side of the connector.
2. Tighten the set screws firmly.
3. Use a lock nut to secure them—this is especially important since vibrations could otherwise cause the screws to loosen during use.

Once properly tightened, the connector ensures torque is effectively transferred from one shaft to the other, giving you the extra reach you need.

Do You Really Need the Longest Flex Shaft?

Most clients insist on getting the longest shaft possible. However, in practice, most blockages occur within 20 meters (65ft), and clean-outs are usually located around 25 meters (80ft) apart. That means ultra-long flex shafts aren’t always necessary for everyday work. Of course, you know your clients’ needs best, but it’s worth keeping this in mind when choosing a shaft.

Another important factor is torque. The longer the shaft, the less torque reaches the tool end, since some energy is lost through friction between the flex shaft and its sleeve—even when it’s well-lubricated.

Why Two Shorter Shafts Might Be Better

Instead of carrying one long, heavy shaft, consider purchasing two shorter shafts and a connector:

• You’ll have less to carry around on-site.
• When extra length is required, you can simply connect another shaft.
• You gain flexibility by combining a thinner shaft with a thicker shaft—getting both the maneuverability of the thinner one and the torque capacity of the thicker one.

Beyond Extensions

Interestingly, some users have found creative applications for shaft-to-shaft connectors. For example, one customer connected a flex shaft to a car polisher using this method, turning it into a power source.

Important Tip: Match Shaft Sizes Correctly

When joining shafts, always remember:

• The thicker shaft should connect to the drill or power tool end.
• The thinner shaft should connect to the working/tool end.

Why? Because a thicker shaft can handle more torque. If a thinner shaft tries to push a thicker one, it can lead to inefficiency or even failure.

Need Help?

If you’re unsure about shaft sizes or setup, don’t hesitate to reach out. We’re always happy to give you advice and make sure you get the most out of your tools.

If you’d like to see a more visual explanation, please check out this video.