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Importing HPGL Files

Use a Graphics Program (Acad|CorelDraw) to Create a Tool PathDrawing.

First draw the part or object to be made. Then use the OFFSET or CONTOUR command to create polygon lines, a distance from the part, determined by the diameter of the cutting tool to be used. For example, if a .25" cutting tip is used, an offset of .125" would be required. Make a special layer just for each tool tip that is going to be used to make the part. Turn off all the layers except the one used for the tool to be used. Then make a plot file of the drawing, make sure the file created will have the normal .PLT extension, for HPGL files. Make different plot files for each tool tip to be used.


How to Import HPGL files

How to Import HPGL Files

With SuperCam loaded, clear the screen with either a close or clearbuffcommand. Then select the INP_HPGL command in the FILE pull down menu, foundat top left of screen. The IMPORT HPGL screen is displayed. At this point the usercan select the file with the mouse or type in a new filename. HPGL files areexpected to have the .PLT extension.

Using the Keyboard Enter key, instead of the Mouse clicking on OK, the following importing options will be presented, before the file is imported.

The first prompt is "Imports HPGL file, Scaling ratio <1.000>:". Byinputing different numbers the the tool path drawing will be dimensionally effected.

The second prompt is "Rotate plot 90 degrees <Yes>: <N|Y>". Theorientation of the tool path drawing can be rotated by this selection.

The third prompt is "Enter filename.<PLT>: ". Only a filename can beentered, the program tacks on the .PLT extension. The file must be in the same directoryas the program.

The file is read and translated into real number coordinates, displayed to the screen andplaced in memory. The command saveas, in the FILE pull down menu, will create a new file or overwrite an old file with the .CAM extension. Once the file has been imported, it's contents can be edited. The order in which the XYZ mechanism does the tool paths canbe changed, along with the direction of movement.

SuperCam has a variable HPinc that can to be changed to scale the dimensionalstool path movements. The command for changing this variable is setHPinc. Differentapplications use different formats of HPGL, subsequently the increments per inchwill vary from one program to the next. We have found with Windows CorelDraw, thevalue of 985 works well, with MAC CorelDraw use the value 3277 and with AutoCad the value of 1016 works well. To calibrate the import command, create a 10 inch line in the application program, import a file with that line, then use the list command to verify that all the line lengths are as they should be. If the coordinates do not match, use the setHPinc command to adjust the variable to get the proper coordinates. Transfer accuracy better than +/-.001" can be achieved.

Configure AutoCad for an HPGL plotter, model HP7245. Make sure the scale is set for 1:1.



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