CNC computer gong processing method (Part 2)

CNC with EDM, copper way:

1. Under what circumstances do you need to be a copper company

If the knife can’t go down completely, it needs to be a copper Gong. In a copper Gong, there are still some that can’t go down. The shape is convex and needs to be subdivided.

The knife can go down, but the one that is easy to break also needs to be made of copper, which depends on the actual situation.

Products requiring spark pattern shall be made of copper.

If the copper alloy can’t be made, the bone position is too thin and too high, and the alloy is vulnerable to deformation. During machining, the alloy will deform and spark will deform. At this time, the insert is needed.

The East-West surface (especially the surface will be smooth and even) produced by copper Gong can overcome many problems in fine Gong and drawing.

When accurate shape is required or there is a lot of allowance, rough copper must be made.

2. The practice of tonggong

Select the surface to be made, complete the surface to be made, or extend the surface to be made, ensure that all edges of the copper are larger than the edges to be made, and do not damage the surface of other products at the same time, remove the unnecessary plane angle (the intersection with the plane angle is the deeper glue position), and make up the regular shape; find out the maximum shape of the copper, use one side boundary, and then project it to the supporting surface; Determine the size of the reference frame, cut off the supporting surface, and this copper map is basically completed; material preparation: length * width * height, length and width ≥ ymax and xmax as the reference frame, the actual length and width of copper material must be greater than the reference frame on the map. The height is equal to or greater than the theoretical dimension of the copper male + the height of the reference frame + the clamping height.

Drawing number determination:

1. When there is no ready-made machining surface, the center of the plane is to * *, the top is to zero, and the top surface is irregular (for copper), leaving a margin of 0.1, that is, when the collision number is 0 (z), the actual value is 0.1 lower than the figure.
2. When there is a ready-made processing surface, make the ready-made surface on the drawing 0 (z), the plane can be divided into the middle, otherwise with the ready-made edge collision number (unilateral) processing surface, check the actual height, width, length and drawing differences, according to the actual material to program. In general, the size on the drawing is processed first, and then the shape on the drawing is processed.
3. When you want to process more than one bit, the first bit (standard bit) needs to set the reference gongs of other bits well. The length, width and height need to be set. All the next processing datum should be based on the surface that has been processed for the last time. Thank you for your attention to CNC automation wechat: cncaut.
4. Positioning of the insert: put it in the whole, pad the lower part with a certain height, and then raise the height of the drawing. The plane is divided according to the whole, and the height is locked with screws according to the figure. If it is square, it can be divided directly. If it is rough, it can be divided by the maximum shape. Cut a fixture, and determine the relative position of the insert drawing and the fixture according to the fixture, and then put the drawing * * in the center of the fixture.

Tool path selection for roughening:

1. Surface trenching

The key is the selection of range and surface.

The area of tool path processing is: the selected surface in the selected range is the end surface, and all the places that the tool can go down from the highest point to the lowest point is the principle. The selected face should be the full face, and the boundary should only be the area to be processed. The distance of the non face should be less than half the tool diameter, because other faces have enough margin, so it is automatically protected. It is better to extend the lowest line, because there is an R Gong at the lowest point.

Selection of cutter: if the cutter can’t feed in helix or oblique line or the area that can’t be machined, the area that can’t feed in the cutter will be sealed and left for secondary roughening.

Before using the light knife, make sure to cut all the uncut areas, especially the small angles, including the two-dimensional angle, the three-dimensional angle and the sealed area, otherwise the knife will be broken. Secondary roughening: generally use three-dimensional trenching to select the range, flat bottom cutter, and use plane trenching and contour cutter path. In the case of no damage to other surfaces, the center of the tool is to the selected boundary. Generally, the boundary is not refined. The fast two-way angle depends on the situation. The angle of spiral feed is 1.5 degrees, and the height is 1. When the groove shape is strip, the oblique feed is used. Generally, the filter is turned on. Especially for the rough surface, the feed plane should not be low to avoid tool collision, and the safety height should not be low.

Back knife: generally, relative back knife is not used, but absolute back knife is used. When there is no island, relative back knife is used.

2. Plane trenching

Milling all kinds of plane, concave slot, when milling part of the open plane, you need to define the boundary, the principle can feed (more than one tool diameter), the open part is more than half a tool diameter, close the periphery.

3. Shape

When the selected plane is suitable for contour layering, lift the cutter by contour layering (plane contour). When the lifting point and the cutting point are one point, it is not necessary to lift the cutter. Generally, lift the cutter on z plane, and do not use the relative height as far as possible; the direction of correction is generally right correction (along the cutter).

4. Tool path setting of mechanical correction

The correction sign is 21, the computer correction is changed, the mechanical correction is changed, the feed is vertical, and where the knife can not pass, the R is increased, leaving no allowance.

5. Contour contour

It is suitable for closed face, open face, if it has four circles, it needs to seal the surface, if it has four circles or not, it needs to choose the range and height (certain arc feed roughening). It is used for roughening: the machining distance in any plane is less than one tool diameter, if it is greater than one tool diameter, it needs to use a larger tool or two contour.

6. Surface streamline

With the best uniformity and dry brittleness, it is suitable for light knife and can replace contour in many cases.

7. Radial knife path

It is suitable for large hole in the middle. Note: the knife is not sharp, the knife is too long, the workpiece is too deep to walk around, not up and down; the sharp corner of the workpiece on both sides of the surface should be divided into two paths, not over the past, the edge of the light knife is best extended (with arc forward and backward knife).

ken.tang @ chengcg.com