Three Tricks for Dealing with Black Marks

The problem of black marks on plastic is often caused by improper power settings. We have tested three adjustment techniques that will help you solve the problem of black marks and improve the quality of your laser engraving.It is suitable for ABS, PP, and other common materials, is easy to use, and has been proven to be effective.

Why does plastic turn black when it's marked?

Plastics are sensitive to temperature, and if the laser power is too high or the parameters are not set properly, the surface can carbonize and turn black.ABS and PP, which are commonly used in 3D printing, have a low melting point, so if the extruder is a bit too hot, it will leave a burn mark.Don't worry, the following adjustment methods can help you get things back on track.

The first technique is to reduce the laser's power.

We started off with a small-scale test.

Don ’ t just use the default parameters! For example, the default laser power is 60 %, but this is probably too high for plastic.They suggest starting at 30 % and gradually raising the rate, while observing the results.If the lines are clear and not too dark, there is no need to raise it.

Different materials require different treatment.

ABS is more likely to turn black than PP, so you can try reducing the power by 5-10 %.If black plastic is used, the power has to be raised slightly (but not more than 40 %) because the darker color absorbs more light.

Second, adjust the frequency and speed.

Don't fill up the frequency band, give the material some 'breathing space.

A high frequency can cause heat to build up.For example, a machine with a maximum frequency of 20 kHz will be more suitable if it is tuned to 10-15 kHz.At the same time, the speed of the laser head is increased, so that the laser beam does not linger on any one point for too long.

Speed and power must be in balance.

If the pattern becomes lighter, don't rush to increase the power. First try lowering the frequency by 2-3 kHz. This will maintain the clarity and prevent the pattern from becoming too dark.

Skill Three: Use Auxiliary Parameters.

Turn on the "power boost" function.

Many machines have this hidden setting, which allows the power to be gradually increased from low to high. This is particularly suitable for complex patterns.Starting at 20 % power and finishing at no more than 35 %, the probability of blackening is directly cut in half.

Don't forget the angle of the blow.

The nozzle of the air-assist is tilted 45 degrees towards the marking area, and the air pressure is set to medium.The gas blows away the carbon and cools the material.If the machine doesn't have this function, a small fan can be used to help.

Adjusting the parameters in these three directions can solve most of the problems of darkened hair.If there's still no improvement, remember to check the cleanliness of the lens--dirt on the lens can cause uneven energy distribution, and the blame falls on your own head.