What’s a fly snipper?

Print anything with Printful



A fly cutter is a tool used in milling machines to make circular cuts on flat aluminum stock. It is commonly used to make clearance notches in automobile pistons and planing a stock square piece. The tool resembles a metal lathe cutting tool and is operated slowly to ensure a smooth and exact cut. It is important to not rush the job and be patient when routing soft material. Carbide cutting tips produce the best results and eye protection and protective clothing should be worn at all times.

A fly cutter is a metal cutting tool used primarily in milling machines. The fly cutter is used to make circular cuts on flat aluminum stock. The most popular job for a flycutter is making clearance notches in automobile pistons and planing a stock square piece. In high performance applications, the pistons must be notched to make room for the intake and more importantly the exhaust valves. Without this additional clearance, the valves would contact the piston, causing catastrophic damage.

The fly cutter tool actually resembles a metal lathe cutting tool. The fly cutter is mounted in a shaft which is inserted into the chuck of the milling machine. The router can be adjusted to the appropriate depth and angle to cut the desired clearance in the top of a piston or any other flat piece of aluminum that the machinist wishes to mill. The router is operated very slowly to ensure a smooth and exact cut.

Cutting soft aluminum is an easy task for the router and fly cutter. The operator should not try to rush the job and should be patient when routing soft material. A forced cut or completed too quickly will result in an uneven, rough finish. On a piston, this will create hot spots which can ultimately lead to the destruction of the piston and possibly the entire engine.

When using the fly cutter for planing or machining a square piece, it is imperative that the tool not be driven fast. Slow and steady cutting will produce the flattest surface possible. When you reach the edge of the surface to be worked, allow the cutting bit to fully advance over the edge before starting the backcut. Most cutters remove some material on the back side of the cutting radius, regardless of how square the workpiece is in the machine.

When using the fly cutter to machine a flat surface, allowing the cutting head to slightly overlap each cut can help ensure a smooth, seamless surface on the finished piece. When using the fly cutter at the correct speed, the chips coming out of the workpiece will be of a curled nature. While some cutters use steel cutting tips, a carbide cutting tip will produce the best results in most cases. As with any cutting tool, eye protection and protective clothing should be worn at all times.




Protect your devices with Threat Protection by NordVPN


Skip to content