Whilst tools are simply referred to as a number in G-code, understanding your tooling is a critical factor of safe and effective use of CNC's. It is important to understand how different tools work, so you can select the right one to use, and when making your toolpaths it helps to input all of the details of the tool into you tool library help you determine the best feeds and speeds, as well as the settings for your passes. Here are a few resources to help you learn about tools
The best way to learn about tools, feeds and speeds in general is by experiencing it yourself whilst operating a cnc, starting with presets or recommended tools, feeds and speeds then get a feel for it. In the meantime though, Onsrud (a tool maker) made a great PDF about it which will appeal to you if you like very technical and thorough documents. Click through check out some of these headings:
This article from make magazine has slightly more approachable language, and it really focuses more on the basics.. This WHOLE THING is worth a read.
Whilst you wait for all of the above information to settle into your mind, at the very least, attempt to keep in mind these Basics Rules for feeds and speeds when your making tool paths:
Having a detailed tool library is useful as a way to store and access all the data about the tools we have, here are some of the tool features of a tool and what we use them for, note the locations of these inputs in the fusion 360 tool library manager screengrab:
Example:
Using more of the length of the flute of a tool will generally improve the finish of a surface when you are doing the final finishing passes after you have finished roughing out most of the materials. It is best to avoid rubbing the area above the flute (the shaft) against the edge of the material if possible
Example:
The number of flutes can be used in combination with the chip-load and the spindle speed to determine feeds and speeds. We use tools with lower numbers of flutes when clearing our large amounts of materials to leave more space for the chip to clear out of the way.
Example:
Body length is the measurement of the amount of the tool sticking out from the collet of the spindle, so it is essential to determining what total depth we can cut to. Keeping an accurate Body length up to date in your tool library also allows you to check for risky collisions when doing complex 3D shapes.
Example:
By adding feeds, speeds, and feed per tooth (or chip load) to your tools, they will automatically populate your tool path strategies when you select the tool. It's important to revise these but having good default settings does a lot of the work for you. Here are some of the important Feeds and Speeds you can set up, note the locations of these inputs in the fusion 360 tool library manager:
This should be determined by testing, or looked up in a tool makers catalog. And along with spindle speed, will inform the feed rate you use. This is also known as 'Chip Load'
This is the speed that the spindle rotates at. Some materials like different RPMs so this will always need revision.
This is the speed at which the tool will move through the material in horizontal or finishing passes.
Example:
These are feedrate associated with moving downward or vertically down through the material, movements which router bits are less suited for. We generally move at a reduced speed when doing this.
Example:
