How to grind the CNC thread knife 60 degrees

The thread knife is divided into internal thread and external thread, but the sharpening principle is the same, the tip angle of the metric thread knife is 60 degrees, and the inch is 55 degrees. The concave sharp angle of the template is aligned with the straight line at 90 degrees and is uniform. When sharpening.

While sharpening, use the tool to lean on the model. until the seam is closed and perpendicular to the template. Then the lower part can be properly sharpened with multiple edges.

The workpiece is turned without collision. The general principle is that the top is wide and the bottom is narrow. Long at the top and short at the bottom.

Introduction: The traditional threading method is mainly to use thread turning tools to turn threads or use taps, plate teeth to manually tap and buckle. With the development of CNC machining technology, especially the emergence of three-axis linkage CNC machining system, a more advanced thread processing method - CNC milling of threads can be realized.

Compared with the traditional thread machining method, thread milling has great advantages in machining accuracy and processing efficiency, and is not limited by thread structure and thread rotation direction during processing, such as a thread milling cutter can process a variety of internal and external threads with different rotation directions. For threads that are not allowed to have transition buckles or retract groove structures, it is difficult to process them by traditional turning methods or taps and dies, but it is very easy to achieve them by CNC milling. In addition, the durability of the thread milling cutter is more than ten times or even dozens of times that of the tap, and in the process of CNC milling thread, the adjustment of the thread diameter size is extremely convenient, which is difficult to do with the tap and plate teeth.

Due to the many advantages of thread milling, the milling process has been widely used in large-scale thread production in developed countries.

Don't have too many front angles, and if you have a large pitch, your back corners should be a little bigger. The cutting speed should be a little higher. Don't go too low.

1.Ordinary steel is brittle if it is hard, and the iron filings are crumbled. If it is soft, it is tough, and the iron filings are in the form of strips, such as precious metals.

The stainless steel material is special, it is relatively hard, and at the same time very tough, so it is very difficult to process, the knife is too sharp to cut and not move, the knife is too blunt to stick to the knife, burn the knife.

2.This requires the use of stainless steel special tools to cut chips, this kind of knife has high hardness, sharpened will not break the tip. In addition, your cutting fluid is also very important, the chip fluid is oily and water-based, as well as neutral, with neutral, the effect will be much better when adding some kerosene to the chips, and the nozzle should be careful not to face all the holes, leaving half of the workpiece.

But be sure to pay attention to fire prevention and leakage prevention. The inner hole knife is not easy to grind, you didn't say how big the hole diameter is, the smaller the less it is difficult to sharpen, it is recommended that you change the special tool for the frame. If you don't have high precision requirements, you can try a 20mm hole.

3.If you currently have to sharpen your own knives, it is recommended that the blade material be low cobalt, ultra-fine particles, ISO standard K cemented carbide. Cast iron cutting knife, the front angle can be ground flat, the rear angle grinding is about 3 degrees, the left and right declination angles are 2 3 degrees, try to be symmetrical, the left and right sharp corners are rounded, if it is a large cutting knife, the fillet is increased accordingly.

1.The knife must be sharpened to a high finish, and if the inclination angle of the blade is sharp, it can be sharpened with a stone stone.

2.Take the outer circle to 90 degrees as an example: the top should be flat and the finish should be high, the chip groove should be wide in the front and narrow in the back, shallow in the front and deep in the back to achieve smooth cutting, and the sharpened props should not have chipping blades, just like the kitchen knife can not have small pits and small openings.

3.Secondly, when sharpening the tool, you should pay attention to whether the slope of the cutting edge is sharp, and at the same time pay attention to what kind of product the tool should deal with.

The rough cutting edge should not be too sharp, otherwise it will not be durable. When slotting on the knife plane, pay attention to whether the iron filings are well discharged; Pay attention to safety when sharpening knives, many people will accidentally grind their hands when they start grinding (note that if the knife touches the grinding wheel too hard, it is easy to grind and slip, and the hand is sharpened to the grinding wheel. ）

You have to be patient, especially when the grinding is about to be done, you should grind gently, and take the thread template at the right angle.

The lathe thread cutter is sharpened according to the following requirements:

The sharpening thread cutter is sharpened with an angle gauge, and the gauge has 60 degrees and 55 degrees of triangular threads, as well as an inch trapezoidal thread of 29 degrees and a metric trapezoidal 30 degrees and a metric worm of 40 degrees.

2.The tip of the tool should have a circular arc, the size is determined according to the pitch, pay attention to the thread rise angle on one side when grinding the cutting edge on both sides, so as not to rub the machining surface during cutting, and the inclination angle of the grinding edge is determined according to the requirements of the machined parts.

3.The size of the blade inclination angle will also determine the flow direction of iron cutting, the general inclination angle of the blade is negative two or three degrees, so that the rigidity of the wire picking knife is good, and the turning is not easy to break the knife, and there is a reverse grinding method, first grind the angle on both sides, and then grind the knife surface, and then repair both sides, the tip of the knife is upward, and directly grinds out an arc.

Sharpening thread cutter with angle model gauge to grind, model gauge on 60 degrees, 55 degrees of the degree of the car triangle thread, there are also inch trapezoidal thread 29 degrees and metric trapezoidal 30 degrees and the angle of the car metric worm 40 degrees, pick what type of wire grinding what angle, grinding the knife and the angle of the model on the back of the coincidence, so that the grinding angle will be more accurate, the tip of the knife should have an arc, the size is determined according to the pitch, pay attention to the thread rise angle when grinding both sides of the cutting edge, so as not to rub to the machining surface during cutting, grinding edge inclination This is determined according to the requirements of the processed parts, the size of the blade inclination angle will also determine the direction of iron cutting, the general blade inclination angle is negative two or three degrees, so that the rigidity of the wire picking knife is good, the turning is not easy to collapse the knife, there is a reverse grinding method, first grind the angle on both sides, and then grind the knife surface, and then repair both sides, the tip of the knife is upward, directly grinding out an arc, (the knife surface has an arc is not slotted, do not pay attention to see it at all) the iron filings out of the car are rolled into a lump, and the chip removal is not easy to hurt people. Much safer than strip chips.

Grind out a tip that is 60° and not too sharp! The small triangle of grinding the sub-cutting surface to 60° obliquely should not be too big or too small, depending on the size of the rib! Thank you.

On the left side there is an increased rear angle (rear angle plus threaded rising angle).

On the right there is the minus trail angle (minus the thread rise angle.

CNC lathes generally use CNC knives, but some knives do need to be sharpened by themselves, which requires someone to teach you by hand, I want to type with you to say it is unclear, go to find a master of your factory to teach you, you will understand!

Pay attention to slotting and grind with heart.

What kind of knife do you have to sharpen.

1. There is a feed box (under the spindle box) at the bottom left of the lathe, and there is a conversion handle on the feed box, which is beaten to the "lead screw" position (the outer circle and inner hole of the car are used"Light bars"）；

2. The pitch of the coarse tooth of M16 is 2mm (if the pitch is not indicated on the drawing, it is a coarse tooth), and the pitch of the fine tooth is used more (the drawing will be marked like this: M16, I don't know what the pitch on your drawing is?).

3. There is a nameplate above the feed box, first find the pitch you need (such as 2mm), and then check what position it corresponds to several handles, and pull these handles to the required position to turn the thread;

4. The feed box and the spindle are linked, as long as the position of the handle of the feed box remains unchanged, no matter how fast the spindle speed, the pitch or feed will not change.

If you want to let the iron filings be discharged along the direction of the small pallet, 1. Strip cutting is possible, and ribbon cutting is something that everyone does not want to see.

2. In addition, the chip chute is also in that direction, which is also impossible.

3. The iron filings touch the opposite face wall and then come out along the direction of the small supporting plate, which has an impact on the machined surface, if it is rough machining, the method is to sharpen the knife in the way of spiral long chips of the outer knife, and the chip groove should be oblique to the direction of the small supporting plate.

The above 3 situations are not ideal, only C-type chip breaking or direct chip breaking is the most ideal, that is, the chip groove is slightly deeper, not too wide. The cutting depth should not be too large, the feed should be slightly faster, and the rotation speed should not be too high.

Of course, there are some materials that are unlikely to break chips, such as aluminum alloy bars and pure iron.

For a very soft material like plastic, it's best to cut it with a ribbon of chips and let it gush out, directly into the distance.

It depends on what shape of knife you use, as well as the speed, and the feed and sharpening of the knife can be well matched.