Cutting Parameters

A set of appropriate cutting parameters is one of the most important technology for getting good machining results. You can set a large group of parameters, e.g. laser power, cut speed, focus position, assist gas, etc, which can control almost every single detail of a cutting process.

Layers

A set of cutting parameters, associated with a layer, will be applied automatically to the parts which are assigned to the layer.

Layers

There are 17 layers in CypCut, the layer Layer 1 to Layer 14 are 14 normal layers which can be machined and have no effect on the processing sequence; the layer Layer 15 and Layer 16 are two special layers which can be machined and will be processed at the beginning and at the end of a job; and the layer Layer 0 is the background layer which would not be machined but for annotation.

In general, different materials with different thicknesses should be machined with different set of cutting parameters. In practice, we recommend creating a one-to-one mapping between the most commonly used materials and the first 10 layers, e.g. 1mm stainless steel to layer Layer 1 , 3mm stainless steel to layer Layer 2 , and temporarily assigning other materials to the 4 layers left when necessary. When setting technology, all you need to do is just assigning the parts of a material to the mapping layer.

To assign a part to a layer, select the part and then click on the button of the layer’s color.

Assign A Part to A Specific Layer

Sometimes, if you want to machine just a part of your design, select those parts that you want to ignore and then click on the button Not Processing to tell the software to ignore them while processing. The parts which are assigned to be not processing are shown in white, but are different with the objects in the background layer. Select the command Select Layer>Layer0 in Home>Select, only the objects in the background layer will be selected.

Assign A Part to Be Not Processing

Click on the button Processing will restore the parts which are assigned to be not processing temporarily.

There are some layer helper functions to help you manage parts with ease while constructing. Select the command Select Layer in Home>Select to select all the parts in a specific layer, already mentioned above. Select the command Lock Layer in the pulldown-menu Home>Layer or in View to lock down the parts in a layer, helping you select and handle the parts in other layers more easily if they are all crowded tightly together. Select the command Show Layer or Only Show in the pulldown-menu Home>Layer or in View to show the parts in a specific group of layers, or show nothing but the parts in the selected layer. This is the other way to control the part of a design for machining because only the parts shown there will be processed.

Layer Helper Functions

Layer Parameters

To set cutting parameters of a layer, there must be at least a drawing element in the drawing window, a part in the part library, or a drawing element in the nest results.

Click on the button Layer Button Layer, you will see tabs for different layers and parameters grouped in the tab Cut, Pierce and Lead for each layer in the pop-up dialog.

Layer Parameters

There are four layers in this example, i.e. layer #1, layer #2, layer #10 and layer #16 which is the special layer processed in the end. They have a same set of layer parameters, including general options, parameters for cutting, piercing and leads.

First, you can give a layer some annotations which help you get to know how to apply this set of cutting parameters, such as the material, the thickness, the nozzle type as well as other matters that need attention.

Then, you can find a group of general options which are placed on the top.

Option Description
Reduce lift The laser head will not lift up when traveling if the start position of the next cutting is nearby and within a pre-defined distance.
Pre-pierce Finish piercing of all or some of the parts before cutting.
Defilm Burn off the protective film on the sheet along the cutting path before cutting.
Recool Blow the assist gas along the cutting path after cutting to get a better cooling effect.
Multi-cut Cut multiple times.
Gas on The assist gas will not be turned off in the whole process.
Not cut The parts of this layer will not be cut.
Not follow The sensor will be turned off and the laser head will not follow the sheet while cutting.
Mode There are three cutting modes. With the Fixed height mode selected, the laser head will be kept at an user set height while cutting. With the Out-plate mode selected, the laser head will be kept at a pre-defined height and start following down to the sheet when it moves into the range of the sheet while cutting.

You can set cutting parameters in the Cut tab.

Parameter Description
Cut speed The nominal cutting speed. The actual cutting speed is often lower than the nominal speed due to the presence of acceleration and deceleration at the beginning, the end and the corners of the cutting path.
Lift height The space between the nozzle and the sheet while traveling.
Nozzle height The space between the nozzle and the sheet while cutting.
Gas type The assist gas for cutting.
Gas pressure Pressure of the assist gas, valid only for gases controlled via electrical regulator, e.g. O2.
Peak power The nominal laser power set in percentage. The actual laser power is often lower than the nominal power when the power curve function is enabled.
Duty cycle Duty of the PWM control signal set in percentage.
Pulse freq Frequency of the PWM control signal.
Focus pos Position of the focus according to the tip of the nozzle.
Laser on delay Time after turning on the laser and before the laser head start feeding when cutting, helping get a better cutting edge at the start positions.
Laser off delay Time after the laser head stop feeding and before turning off the laser when cutting, helping get a better cutting edge at the end positions.

You can check the option Slow start and Slow stop to get a better cutting edge at the start and the end positions when cutting very thick sheets. Set the length of slow feeding in the option Length, set the feeding speed in the option Speed.

Sometimes, especially when cutting thin sheets with high cutting speed, the material will catch a lot more power at the start, the end and the sharp corners because of the low feeding speed at these positions and result in over burnt edges. In these cases, you should set variable laser power or set variable laser frequency if the material is more frequency sensitive according to feeding speed.

Double click on the laser curve or click on the button Edit to open the laser curve editor.

Laser Curve

The power curve is shown in orange and the frequency curve is shown in blue. Here we walk through the power curve construction, you can construct the frequency curve in the same way. Click on Add, Delete or Clear to add, delete or clear key points on the curve. Choose different curve pattern from the option Pattern. And you can save the laser curve to or load it from an external file.

You can set piercing parameters in the Pierce tab.

Pierce Parameters

There are four piercing modes, no piercing, single stage, two stages and three stages piercing. Each piercing stage has a same set of parameters.

Parameter Description
Step time The feeding time from the piercing height of the current stage to the height of the next stage.
Pierce height The initial space between the nozzle and the sheet in the current piercing stage.
Pierce gas The assist gas for piercing.
Gas pressure Pressure of the assist gas, valid only for gases controlled via electrical regulator, e.g. O2.
Peak power The nominal laser power set in percentage.
Duty cycle Duty of the PWM control signal set in percentage.
Pulse freq Frequency of the PWM control signal.
Focus pos Position of the focus according to the tip of the nozzle.
Pierce time Time after turning on the laser and before the laser head start feeding down when piercing.
Extra Blow Time after turning off the laser and before starting the next stage. Check this option if you want to put an extra cooling on the material.

You can set leading parameters in the Lead tab.

Lead Parameters

Sometimes, e.g. when cutting thick stainless steel, the piercing process will create a massive cloud of plasma which will catch a lot of laser power and result in very bad cutting results. In these cases, you should enable the special technology for leading in to lift the laser head up after piercing, blow off the plasma cloud and feed the laser head back down, and then start cutting.

Lead Parameters Illustrate
Parameter Description
Use Leadline Technique Enable the special technology for leading in.
Cut speed The nominal leading in speed, should be lower than the normal cutting speed because a part of laser power is caught by the plasma cloud.
Duty cycle Duty of the PWM control signal set in percentage.
Pulse freq Frequency of the PWM control signal.
Lead Down Lift the laser head up after piercing.
Lead height The initial space between the nozzle and the sheet, should be high enough to blow off the plasma cloud.
Stable distance The distance between the start position of the contour and the position where the laser head should completely feeding down to the sheet.

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