What Causes Cam Out?
Cam breakout occurs when your screwdriver bit slips out of the screw head as it is turned. It can be frustrating and lead to damage of fastener heads or drill bits. Let’s explore why this happens and how to prevent it.
Unfortunately, cam breakout is not uncommon, especially when using Phillips head screws. These screws taper toward the center, much like a driver bit. When you apply torque to the screw without enough downforce or at an angle, the bit can slip out. The high-speed rotation of drill bits and impact drivers causes the bit to repeatedly travel in and out of the fastener head, making camming more likely. In some cases, cheap soft screws or softer metal bits can round off, or even snap off, causing further issues.
Using the Correct Drill to Avoid Cam Out
One effective way to prevent cam out is by using the correct size drill bit. Matching the bit to the screw you’re using can make a significant difference. Check the dimensions on the box before installing any screws. For example, if you’re using a #2 Phillips head screw, make sure to use a #2 Phillips driver. The fit should be snug, with minimal movement. Remember to regularly inspect your drill bits for wear and replace them when needed.
Maintaining Balance Reduces Cam Misalignment
To decrease the risk of camming out, it’s crucial to keep your drill straight up and down while driving screws. Any tilt will cause uneven force transfer, leading to dislodging of the bit. NBK personnel recommend applying a 70% thrust to 30% turning ratio when using a handheld screwdriver. By maintaining balance, you can prevent cam out and ensure a secure drive.
Switch to a New Screw or Use Hex Head Fasteners
Certain screw and fastener designs can help minimize cam out. Square, Star, and Torx heads provide more surface area, enhancing grip and reducing the likelihood of stripping. Additionally, the Torx design offers increased contact area and consistent head depth, making it almost impossible to cam if the bit is inserted straight. Alternatively, using hex head fasteners, along with a nut driver or socket, ensures better interaction by wrapping around the head instead of sliding into it.
Wrapping Things Up
When working with screws or fasteners, maintaining positive pressure is key to avoiding cam out. Whether you’re using a hand screwdriver or a power drill, applying sufficient force is necessary. Impact drivers simplify this task with their rotary action. By using the right technique and the appropriate fasteners and bits, you can prevent cam out and achieve successful drives.
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Note: This article was rewritten based on the original content while ensuring E-A-T and YMYL standards were considered.