Test Cut

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  Test Cut:
  • Principle: 
The [Test Cut] menu is used to calibrate your foam cutter by performing a battery of longitudinal (lengthwise) cuts in a block of know height.


 






Let us consider the following example :

    Your foam block has a height of 100 mm,

    You decided to cut a slice evry 10mm,

    The number of cuts will be 9

    If after the cuts, the remaining height is only 90 mm

    Then the thickness of the cut is
    (Height before cuts - Height after cuts)/Number of cuts

    (100mm-90mm)/9 = 1.111 mm for each pass.

    This represent the virtual diameter of the cutting wire, including the melted foam. As you know the actual wire diameter and the cutting speed, you got all the data to define the wire kerf compensation for this type of foam and these operating conditions.
     

  • Menu:
DécoupeTest.jpg (34547 bytes)







Other Examples:

  • Cutting a circle:  

    •  

     

    A good way to test your CNC foam cutter and the software configuration is to perform a circular cut. To do this, you can use  the coordinate file  cer_25.cor . You can define the dimension (diameter) of your cut by modifying the chord value. The result is shown on the following photograph. Notice the differences between the two parts : one has been cut with the spline function activated. On the other one (labelled 'sans spline'), the facets are visible.
     
     


The same profile (coordinate file) may be used for cutting fuselages or others. Refer to Examples page.
    Example of a wire kerf test for a trapezoidal cut :
Initial data: 
    Cut 7 slices, 5mm thick, width 700mm in expanded polystyren.
     

    Test repeated with 3 trapezoidal foam blocks, root chord 100mm and tip chord respectively  75, 66 and 50mm. 

The result is interesting. The wire kerf effect is more important within the foam block. In order to get a better cut, 2 cm should be thrown away at each foam block extremities.
 

  • Example of a test to assert the variation of wire kerf
Test Condition :
  • Prepare your result sheet ( Réglage Rayonement.xls ) 
  • Cut some small foam blocks  (8cm*4cm)
  • Measure precisely the height of each block
  • For each of the three tests, the wire heater power should be constant
  • Fill in the 'Test Cut' menu to cut a rectangle
  • If you are willing to test multiple materials, you can set one type of foam left, another in the center and a third right. So you will perform test for 3 materials simultaneously.
  • Perform a cut et measure the resulting height
  • Go on testing with other speed values
  • When the whole speed range is covered, you can restart the procedure with other wire heater power adjustments.
Utimately, you should obtain series of curves like those: