Isolation Milling

Our micro cutting bits offer a superior option to flat end mills for milling certain traces and pads. Their tapered design allows for more metal, making them stronger and less susceptible to breakage compared to end mills.

Even the narrowest micro cutters can mill at high speeds and in a single pass, making them ideal for milling circuit boards with small features. They are the recommended choice for Isolation milling.

For Isolation Milling flat end mills also have some drawbacks. One of the main downsides is that the very small tools, are quite delicate and prone to snapping.  To prevent breakage, these tools require slower feeds and speeds, as well as multiple passes.  Consequently, using small flat end mills can result in lengthy milling jobs.

The life of the router is dependent on a number of factors including feed rate, speed, material characteristics, and what the user considers acceptable milling quality. 

To ensure consistent plunge depth for all bit diameters, we suggest using depth setting rings when fitting your bits. You can easily set the plunge depth stop on your drill press to a single value.

All of our router bits are available with or without rings, and you can customise the depth ring position to meet your needs.

Choosing The Right Angle

45° Vs 60°

Calculating the milling Depth

45° and 60° micro cutters


We offer 45 degree and 60 degree cutters from stock, Running on 3.15mm 1/8" shanks.

Our micro cutters can operate at upto 80,000 RPM. You should run as fast as possible whilst not exceeding the maximum rated speed. Cut rate and dwell time should be adjusted to provide best isolation quality and minimal burr.

Refer to the Technical Data Sheet for specific recommendations.

Yes, we offer a ring setting service. We can fit rings to your drills at the time of purchase. We will keep a record of your drill ring distances, so that upon re-order, we can set the rings to the same position. Review our drill ring setting page.

For isolation milling Flat end mills need to be small to enable close track to track gaps. These small sizes, are fragile and can be easy to snap. To avoid breakage, they require slower feeds and speeds, multiple passes, and can result in long milling jobs.

The Old Station Yard, Station Road
Wilburton. CB6 3PZ
Great Britain

+44 (0) 1223 901890

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