Views:40 Author:Site Editor Publish Time: 2019-08-05 Origin:Site
Metal parts are relatively simple. After all, if the metal CNC manufacturing, this kind of work is much more skilled. Generally speaking, it will not be a hand-made tide for a few years. The difference lies in the different metals. This is relatively good to say something.
CNC processing plastics are prone to cracking due to internal stress. In addition to controlling the speed of the knife, it is also necessary to pay attention to the cooling. It is not necessary to cool down.
CNC processing plastics have a certain temperature.
It is low, easy to crack, deformed, and burrs will hurt the angular position. More obvious is acrylic, the corners are prone to collapse.
When it is high, the contact position will melt and wrap around the knife to form a bond. The processing surface will form a white "film" shape. Can't wash it, can't wipe it off.
The surface is easily scratched. After all, the hardness is low. Plates and bars need to pay attention when buying raw materials, and the surface protective film is selected to be completely scratch-free. Candidate faces are also important during processing. On which side the machining is to be confirmed. Where and where you can't hold it.
The processing table and the clamping mechanism must also be cleaned. Otherwise, just dry the plastic after processing the stainless steel. The result is a one-by-one. There is also something like a vise that can best be something. Many of the vise clamping positions are tooth-shaped structures, and the metal parts are gone. PE, PVC, ABS, and POM are all unstoppable.
CNC preparation for plastic processing. First, the material is good. Depending on the material, it is immersed in hot water to release the internal stress of the material.
A major problem with manual processing of plastics is the similarities and differences in processing relative to other materials, such as CNC manufacturing of metals. What are the main cutting, planing, welding, drilling, surface treatment, etc?
Mainly a word "try".
Why do you say that? Because of the plastic thing, the performance is very different. It can be said that these years, I have not seen such difficult materials. The results of different batch feed treatments are different.
You think it is PVC. Actually, it may be PE. You want PE. It may be ABS. It can be the plastic on the machine. It is difficult to tell which one is from the appearance.
For example, there is a PVC bar. PVC is soft and hard, transparent and opaque, different products, different formulations, plus plasticizer and filler, there is no difference, the density is very different, ordinary hard The transparent PVC is about 1.34 g/cm3, and the opaque hard PVC is also 1.7. The transparent soft PVC is as small as 1.22, and the difference is 0.5, which is 40% difference in weight.
To say other materials, such as metal CNC manufacturing, the same size, color, weight, feel, and even smell, you can have a number. Really not, like 304 and 316 stainless steel rods, go to bed, have an experienced knife to see the debris know what the hand is. Plastic does not look at the outer protective film logo, can not be judged casually.
There is a method of partial door recognition. Not recommended, but experience can still be used as a basis for judgment. That is "甩"! A bar with a certain length, when the samurai sword is like a hollow, observe the amplitude of the shake and then use what is done in the drawing, basically you can roughly judge the type of material. That's right, the legendary "shaking the spirit" 233 is good, just say what to do with the manual. First of all, because plastics are generally not too hard, sometimes you can refer to the woodworking process. I just said that sometimes! Don't be all the time, if you can't afford it, you can't afford it.
For example, planing, this general plastic processing is not used, because the material itself is flat or too much, the plastic is too flat relative to the wood, generally not used.
For rough cutting, it is recommended to open a row of fine holes and then cut along the path with a saw. This has the advantage that it is not easy to stick to a knife or saw. The downside is that the interface is jagged and must be post-processed. At this time, it can be cut, it can be flattened with a hanging mill, then the trimming machine is refined and chamfered. Finally sandpaper is polished. This is the way to treat the sheet with a thicker cut surface. Thinner, such as 1 to 3 mm, can be considered to be cut with a wire saw, or a brittle, direct utility knife like acrylic. If you are in the arc, remember that the result of one knife and one knife is very easy to crack. I am not sure that the perfect solution will be solved in the end. In addition, for some low melting points, you can trim with an electric iron. But, still, let's experiment with waste! Remember! No one knows what the hell is in your hand! Pay attention to labor insurance!
In addition, there is a problem with gold plating here. Many plastics have a low melting point and can be bent. A metal stick is placed in a position where it needs to be bent, and then the sheet can be bent. Pay attention to the temperature here, don't burn it.
Finally talk about drilling this thing. I don't know what connector you usually use. Bolts are definitely indispensable. So the question is, metal bolts or plastic bolts?
There are not many precautions for metal bolts, mainly two things when tapping
1. Clean the workbench, especially with a tapping machine! A little oil can make your work dry all over the place. Plastic cooking oil is directly infiltrated. The basics such as detergents are not clean, steel balls, all kinds of decontamination sponges known as fried chickens, and even bathing towels I have tried, the only way is to sneak into the depths, and quickly use the knife. However, the surface is destroyed after the surface is scraped. Do you say that this job is not hard to please?
2. When the standard connector is used, tap the wire hole, which is slightly smaller than the metal piece. For example, the hole of M6, if you remember correctly, the metal is 4.9~5.1.pom. I usually use 4.7 or 4.8. The disassembly and disassembly of the two holes will be abolished. Also, be careful when designing, at least 5 threads of depth. The reason is still soft. The first two turns of the thread at the beginning are not available for manual tapping or machine tapping. The tooth itself is soft, and the first tooth at the beginning of the installation is slightly broken, and then the chain reaction.
There is a way to solve this problem, the wire sleeve, the wire sleeve. It is the kind of thing that looks like a spring, and there are silk inside and outside. First open the bottom hole, do not tap the wire, the wire sleeve is hard screwed in. How to use the bolts later, no delay. However, there is a pit here. The upper sleeve means reaming, and the M6 becomes M8. Reaming means that the hole must be moved inward, and it will interfere with other things inside, which depends on the design. And the distance from the hole to the side should also be tested. Otherwise, it is easy to fry holes in the actual process.