Squeegee pressure, sharpness, and contact position with the plate all have an impact on print quality. According to actual needs, reasonable adjustment of these factors can solve many problems in printing.
1. Pressure
The factors that affect the pressure of the doctor blade are the size of the cylinder pressure, the difference between the hard and soft blades, the angle at which the doctor blade and the printing plate cross, etc. Excessive pressure will reduce the transfer rate of the ink and cause greater wear on the printing plate and blade; too small pressure is prone to dirty plates or scraper lines.
2. Sharpness of the knife
The sharpness of the knife depends on whether it is a new knife, the blade angle when sharpening, the type of sandpaper (stone) used, etc. The appropriate sharpness of the knife should be effective to scrape off the ink without generating wire. Too sharp scrapers are often prone to traces of wire, while at the same time wearing plates.
3. The distance the squeegee touches the printing plate
The reduction of the distance between the blade and the printing plate is helpful to improve the ink transfer rate, but it is easy to produce dirty plates; on the contrary, it can effectively solve the dirty plate and avoid some small line marks, but it will reduce the ink transfer rate.
4. Flatness of the knife
The flatness and warpage of the knife mainly depend on the installation method. Of course, it may also be related to the adhesion of foreign objects in the slot of the knife holder or on the blade and the lining.
When the flatness of the knife is poor, some bead-like marks will appear on the edge of the printing surface, or some intermittent line marks will appear from time to time. Some people think that the above phenomenon will only occur if the ink is rough and the ink flow is not good. In fact, this situation can also occur when the knife is uneven.
5. The movement of the doctor blade
The movement of the doctor blade to the left and right has an important effect on reducing the doctor blade line, improving the doctor blade utilization rate, and reducing the abrasion of the plate. If the squeegee moves abnormally, you should try to improve it.
When line marks appear in printing, one is causing plate damage, and the other is that the scraper is not sharp. However, another reason is that foreign objects are stuck behind the blade. The solution is to move the squeegee back and forth up and down in order to get rid of the sticky objects. If you can't get rid of it, you can only stop and wipe the squeegee.
Another problem is related to the squeegee, and many people misunderstand that it is caused by ink. This refers to the occasional appearance of dozens of irregular line marks of varying lengths, which look like they are piled up by ink. It is different from the scraper line. It is not continuous, but sometimes there is no. This is actually the scraper. The pressure is too low or the scraper is not sharp enough.
Several indicators of the above scraper have both differences and similarities. When solving specific problems, one of them can be used, and sometimes it needs to be comprehensively applied to completely solve the problem. For example, when there are some intermittent ink lines, it can be solved by increasing the pressure, or by sharpening the knife; when there is a serious dirty version, it needs to be combined in several ways; first, use a sharp blade, two To increase the pressure, the third is to increase the distance between the blade and the contact surface.
When the squeegee is seriously worn and cannot be ground with sandpaper or oilstone, it can be honed with a special sharpener so that it can be reused several times, greatly reducing the cost of the squeegee.
Tv Mount,Wall Mount Screens,Adjustable Mobile Stand,Tiled Screens Wall Mount
Dongguan Aoxing Audio Visual Equipment CO.,Ltd , https://www.aoxingaudio.com