Matching Insert Shape and Holder Code: The second character in a holder code represents the insert shape, and it should match the first character of the insert code if you want to use them together. For example, if an insert has a rhombus shape with an angle of 80 degrees, its first code character will be "C". To use this insert with a holder, the holder's second code character should also be "C", matching the insert shape. This ensures that the insert fits properly in the holder and functions effectively during machining.

It was like the trees were trying to get away from something on the road. Logically, they should have been moving towards the road because it had greater sun light. Why were they moving away from the road ?

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Holder Lead Angle: The third character in a holder code represents the holder lead angle or approach angle, which is the angle between the cutting edge and the workpiece. Different lead angles are represented by different characters, as per the standard followed. For example, if the lead angle is 93 degrees, it is represented by the character "J" in the holder code.

Other clamping methods such as top wedge lock (represented by "M" in the holder code) and lever lock (represented by "P" in the holder code) are also used, and some manufacturers may have their own specific clamping methods.

The arrow next to each property indicates the direction in which it increases. Here’s how you interpret the picture:– Vibration during cutting: This is lowest for V shape, highest for R.– Ability to turn complex contours: R is the least versatile, V is the most.– Spindle power requirement: For a given set of cutting parameters, V requires the lowest spindle power, R requires the highest.– Strength of insert: V has the lowest strength, R is the strongest.– Ability to take heavy cuts: V has the least ability to take heavy cuts, while R has the highest.

I still don’t have an answer to the question, and think it might be one of these: 1. The tar on the road gets uncomfortably hot, and the trees are bending away from the heat. 2. The vehicles moving on the road caused a wind to blow, and the trees were bending away from the road from even as tiny saplings. 3. Even the trees can’t stand the vehicular pollution, and bend away from it. Except the CO2 of course, which they ingest. The other stuff they probably hate – CO, NOx, SO2, the Lead. I like to think it’s the last reason. If I’d been a tree, I definitely would bend away from the pollution.

Turning inserts are essential tools used in CNC turning machines for cutting and shaping workpieces. Along with turning inserts, turning holders play a crucial role in the machining process. In this blog, we will delve into the world of turning insert holders, focusing on their coding rules and clamping methods.

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Why all those bent trees ? I was jogging near Marina beach in Chennai one morning, and noticed that a lot of trees on the footpath were bent away from the road. Not just a few random trees, but most of them. Either the trunk itself was bent away from the road, or the foliage was concentrated on the side away from the road.

Rigid clamping, represented by "D" in the holder code, is a stronger method where a pin goes through the insert hole and fixes the insert in place by pushing it downwards. However, it may not be the most suitable method for internal machining or boring due to its bulky nature. Holders used for roughing or operations generating high cutting forces may have shims made from hard material to distribute force and extend the life of the holders. Shims are replaceable components that can be easily replaced if damaged.

Conclusion: Turning insert holders play a crucial role in the machining process, providing stability and accuracy to the cutting operation. Understanding the coding rules and clamping methods for turning insert holders is essential for selecting the right holder for specific machining operations. By matching the insert shape and holder code, and considering factors such as clamping method and holder lead angle, you can ensure efficient and effective turning operations in your CNC turning machine.

Holder Coding: Turning insert holders are coded to indicate various characteristics, such as insert fixation method, insert shape, holder lead angle, and more. The coding system may vary depending on the manufacturer and the standard followed. For example, in a standard coding system, the first character in a holder code represents the insert fixation method. "S" indicates screw clamping, "D" represents rigid clamping, "M" denotes top wedge lock, "P" signifies lever lock, and so on. The choice of insert fixation method depends on factors such as cutting forces, accessibility, and type of machining operation.

Clamping Methods: Turning insert holders use different clamping methods to securely hold the inserts in place during the machining process. Screw clamping, represented by "S" in the holder code, is a common method used for positive inserts, where the clearance angle is not zero. Although it is considered weak in comparison to other methods, screw clamping is compact and provides accessibility, making it suitable for internal or boring machining and operations with lower cutting forces.

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When we select an insert for an operation, we select it based on these characteristics: – How versatile it is in cutting different part contours– Spindle power required to cut– Vibrations during cutting, which are a result of the extent and direction of cutting forces– Strength of the insert and its ability to take heavy cutsThis picture shows how the characteristics change with the turning insert shapes.

Action point Please consider these characteristics when selecting an insert for an operation. It takes very little time, but can make a big difference to cycle time and profitability.