Posted on: Aug 3, 2018, | By Kenzi, WayKen Project Manager
With the development of the machining technologies, the CNC processing also develops a lot recently, many professional specialists said that in the coming decades, CNC will be the mainstream of machining modes, furthermore, among the CNC machining, tools are the most important parts, now let’s talk about the CNC tools.
CNC Tools Introduction
Tools are used for the cutting and machining of machinery manufacturing. In general, the cutting tools include the cutter and grinder, most of the cutters are used in machining, but there are also manipulative tools. As the machinery manufacturing tools are widely used on the cutting of metal materials, thus the cutter for this are called as metal machining tools, and those cutters for wood are called as wood tools.
The materials of CNC tool must be harder than the aluminum CNC parts which are to be cut, and the chosen tool must be able to withstand the heat created in the metal-cutting process. Also, the tool must have a specific geometry, with clearance angles designed so that the cutting edge can contact the working aluminum parts without the rest of the tool dragging on the aluminum surface. The angle of the cutting face is also important, the same with the flute width, number of flutes or teeth, and margin size. In order to have a long working life, all of the above must be optimized as well as the speeds and feeds at which the tool is run.
CNC Machining Tools Category
There are 5 categories based on the surface finishing of the aluminum parts
-Tools for various outer surface: including turning tool, planer tool, milling tool, scraping out cutter, rasper.
-Tools for the holes: including driller, reamer, boring tool, milling cutter and inner surface scraping out cutter.
-Tools for threads: including screw tapper, threading die, self-opening die head and self-collapsing tap, thread cutter, and thread milling cutter.
-Tools for gears: including hobbing cutter, slotting cutter, gear shaving cutter, bevel gear cutting tool.
-Cutting off tools: including inserted saw blade, band saw, bow saw, cutting off tool, metal saw.
The structure of the tool consists of clamping part and working tool part. The whole structure of a complete tool normally contains the tool main body for this clamping parts and working tool parts. The clamping part has hole type and handle type. The hole type assemble on the main shaft or core shaft by the inner hole, then turn the moment by relying on the straight end-face key, such as the cylindrical milling cutter and shell face milling cutter.
The handle type normally has rectangular handle, cylindrical handle and taper handle. The milling cutter and planer tool are usually belongs to the rectangular handle type; the taper handle withstands the axial trust by the taper, and transmits the torque through confliction. The cylindrical handle type suits the small tools such as twist drill, end drill; while such tools are cutting, they will transmit the torque force by the clamping confliction. Most of the handle type are made by steel alloy, while the working tool parts are made by high speed steel then weld these two types together to get a complete tool.
High Speed Cutting Tool Structure
The basic performance of the high speed tool
- High hardness
The hardness of the tool must be higher than the aluminum cnc parts, this is the basic character.
- Enough strength and toughness
The cutting tool needs to withstand a high cutting force and impact, the anti-bending strength and anti-impact reflects the strength and toughness performance of the tool.
- High abrasive performance and heat resistance
The abrasive performance of the tool is the ability of anti-abrasion. The higher the material hardness is, the better the anti-abrasion the tool is. And when the heat is getting higher, the ability of heat resistance will be better means the tool is better.
- Good thermal conductivity
The higher heat conductivity ratio means the tool is easy to transmit the heat while machining, thus to reduce the abrasion of the tool.
- Better manufacturability and economical efficiency
In order to be easy to machine, the tools need to be good manufacturability, including the forge and stamp, weld, cutting, heat treatment and grindability. The economic efficiency is one of the most important characters of evaluating and popularizing of a new tool.
This is to prevent the cohesiveness between tool and aluminum cnc parts under high temperature.
- Chemical stability
This refers to the character of a tool that is not easy to perform any chemical reaction with surrounding substance.
The choice of CNC tools depends on the operation of programmer and machines. This should base on the processing ability, material performance, processing procedure, cutting volume and so on to choose the right tool. In general, they are easy to assemble or disassemble and are of durability and high precision. In order to fulfill machining requirements, it is often to choose the short handle so that to improve the toughness of the cutting tool and make the tool dimension and parts dimension in the same surface tolerance.
The coating layers of the tool are also very important. The aluminum indexable blade nowadays uses the chemical vapor deposition to cover the titanium carbide, titanium nitride and aluminum oxidation layers. The developing of the physical vapor deposition is not only used on the aluminum tools, it can also apply on the high speed steel tools, such as the drilling tool, turning tool, tapper and cutting tool. With this layer, the life of the tool can improve 1-3 times.
As there are more and more difficult materials now, the precision requirement of the CNC machines become higher and higher. In order to fulfill such requirement, the development of the tool would be to improve the new material, coating layer technologies, the structures and tool precision to make the tool becomes better and better. Only in this case, we can machine more and more high precision metals mechanical parts for automotive usage and machines.