20 CNC machining skills

2023-12-13 09:51:05

article 20 CNC Machining techniques :

1. white steel knife speed can not be too fast.

2. Copper workers use white steel knives less for coarse driving, and fly knives or alloy knives more often.

3. When the workpiece is too high, it should be thickened with knives of different lengths in layers.

4. After coarsening with a broadsword, use a knife to remove the remaining material and ensure that the remaining amount is consistent before smoothing the knife.

5. The flat surface should be processed with flat-bottomed knives, and less ball knives should be used to reduce the processing time.

6. When the copper worker clears the angle, first check the size of R on the angle, and then determine the size of the ball knife.

7. The four corners of the calibration table plane should be flat.

8. Where the slope is an integer, use the slope knife processing, such as pipe position.

9. Before doing each process, think clearly about the margin left after processing in the previous process, so as to avoid empty knives or excessive processing.

10. Try to take a simple knife path, such as shape, digging grooves, one side, less around the same height.

11. When walking WCUT, if you can walk FINISH, don't walk ROUGH.

12. When the shape of the light knife, first rough light, then fine light, when the workpiece is too high, first light the edge, then light the bottom.

13. Reasonably set tolerances to balance machining accuracy and computer calculation time. When the thickness is opened, the tolerance is set to 1/5 of the allowance, and when the knife is polished, the tolerance is set to 0.01.

14. Do a little more work to reduce the empty knife time. Do a little more thinking, reduce the chance of error. Do a little more auxiliary line auxiliary surface, improve the processing condition.

15. Establish a sense of responsibility, carefully check each parameter, avoid rework.

16. Be diligent in learning, good at thinking and making continuous progress. Milling is not flat, use more ball knives, use less end knives, don't be afraid to pick up knives; The knife clears the angle and the broadsword refines. Don't be afraid of mending the surface. Proper mending the surface can improve the processing speed and beautify the processed fruit.

17. The hardness of the blank material is high: the reverse milling is better. The hardness of the blank material is low: the forward milling is better. The machine tool has good precision, good rigidity and finishing: it is more suitable for forward milling. On the contrary, it is more suitable for finishing the corners of the reverse milling parts. It is strongly recommended to use forward milling. Rough machining: reverse milling is better, finishing: forward milling is better. Tool material has good toughness and low hardness: it is more suitable for rough machining (large cutting amount processing). Tool material has poor toughness and high hardness: it is more suitable for finishing (small cutting amount processing).

18. Copper male processing method and matters needing attention: before writing the tool path, after drawing the three-dimensional drawing, move the center of the figure to the origin of coordinates and the highest point to Z = 0 before processing, and the copper male spark position can process the negative reserved amount.

Before processing, check whether the clamping direction of the workpiece is the same as the graphic direction in the computer, whether the ranking in the mold is correct, whether the clamping fixture hinders processing, and whether the directions of the front and rear molds match. Also check whether the tools you use are complete, and check the benchmarks in the table. Matters needing attention in processing copper male: the determination of spark position, the reserved amount of general young male (I .e. fine male) is 0.05~0.15, and that of coarse male is 0.2~0.5. the specific spark position can be determined by the master who makes the mold. Is there any dead corner that the copper male cannot process, and whether it is necessary to dismantle another loose male. The knife path of copper workers is generally arranged in rows: broadsword (flat knife) open thick-knife (flat knife) clear angle light knife ball knife light curved surface. Generally speaking, teachers use a flat knife instead of a ball knife, use a knife after a large knife to make a rough knife, then light the shape to several, then use a large ball knife to light the curved surface, and then use a small ball knife to light the curved surface. It is not convenient to use a small knife to process dead corners that a large knife cannot pass for small angular positions, so as not to broadcast too many empty knives. Copper male, especially young male, is relatively high precision requirements, tolerance is generally 0.005~0.02, step distance 0.05~0.3. When the copper is publicly thick, it is necessary to leave the over-cutting position of the ball cutting position, that is, to open the copper male shape by one knife radius. The copper male also needs to process the middle and calibrate the table reference. The copper worker must be calibrated during spark discharge. Generally, the copper worker machined 3 one surface (upper, lower, left and right) must have a 3 reference surface. Copper is a relatively easy-to-process material. The cutting speed and rotating speed can be faster. When roughing, the machining allowance is 0.2~0.5, depending on the size of the workpiece. The machining allowance is large. When roughing, the cutting speed can be faster and the efficiency can be improved. Note: The parameters in brackets are the parameters when the high-speed steel knife roughens the steel material. The above cutting speed means that when the steel material is roughed, the light outside F = 300~500, and the steel material light knife F is 50~200.

19. The problem of opening the front mold: First, rotate the copper male drawing 180o in the front view or side view to become the front mold drawing, and of course, add the pillow position and PL plane; Where the original body needs to be left in the front mold, do not use the mirror body method to change the copper work drawing into the front mold drawing, which is sometimes wrong (when the X direction and Y direction of the copper work drawing are asymmetrical). There is 2 difficulty in the processing of the front mold: the material is relatively hard; The front mold cannot be easily welded and cannot be wrong. The principle of using a knife when opening the front mold is similar to that of a bronze worker. The big knife is used for opening the rough knife → the big knife is used for opening the rough knife → the big knife is used for opening the rough knife → the big knife is used for opening the rough knife. The big knife handle () is usually used for opening the rough knife. When opening the rough knife, the round nose knife is also used as much as possible. Because this knife is large and powerful, usually, there is a problem that when the knife is polished, the type surface will encounter the machine key Lou number, and the cavity will have to leave 0.2~0.5 machining allowance (sparks will be left). This is to correct 0.2~0.5 on the surface of the mold cavity in the positive direction, and set the machining allowance to 0 when writing the tool path. When the front die is opened thick or smooth, it is usually necessary to limit the range of cutting. Remember that the range you set is the range of the tool center, not the range of the tool boundary, not the range of the tool processed by the tool, but a larger tool radius. The common tool path method for front mold opening is curved surface grooving and parallel light knife. When the front mold is processed, the mold surface and the pillow surface are generally processed to the standard number, while the contact surface can be left with 0.1 allowance for mold matching.

20. Problems often encountered in the post-processing die: the post-processing die has 2 kinds of primary or inlay sections. The post-processing die is made of steel like the front die, and the material is relatively hard. The tool handle should be used as much as possible. The common tool path is curved surface grooving shape and parallel milling of light tools. The principle of tool selection is that the large tool is thick → the small tool is thick → the large tool is thick → the large tool is smooth. The rear mold drawing is usually made by reducing the material level of the copper male drawing plus PL surface, pillow position and things left by the original body. If the material level is relatively uniform, the negative material level can be directly left in the processing information, but PL (parting surface), pillow position and contact surface cannot shrink the material level. At this time, you can first correct a material level or draw the section.

One of the problems often encountered in the original body department is that the ball knife cannot clear the angle. At this time, a flat knife can be used to clear the angle on the steep inclined plane of the curved surface. For example, the rear mold is divided into a hidden frame and a core. When adding the hidden family, attention should be paid to walking the empty knife several times. Otherwise, the frame will have slope, the upper side will be accurate and the lower side will be small. It is difficult to match, the light frame knife should also be new and better, and a bigger knife should be used. If the core is too high, it can be turned over to process the frame position first, then assembled into the frame, and then process the shape. Sometimes there is a branch opening. Attention should be paid not to protect the branch opening step when overcutting the light shape with a ball knife. In order to facilitate the matching mode, the frame size can be smaller than the core shape size -0.02 m/s. The tolerance and step distance of the core light knife can be slightly larger, and the tolerance is 0.01~0.03. The feed is 0.2~0.5.