Hook Selection File

The customer has a possibility to set-up the system to select burning hooks in holes from the ones defined in the nesting system. This set-up is done by a "hook selection file", which is an ordinary ASCII file with the following contents:

Hole type   Thickness   Start hook   End hook

The selection is done by searching for the correct hole type, for example, 'D'. If this is found, an exact match of the hole size, for example, '50' is searched. If the hole size is not matched, the closest smaller hole size, for example, '30' is used. The thickness of the current plate is then compared to the thickness for the hole type in the hook selection file. If the plate thickness is not matched then the definition with the closest smaller thickness is selected.

Example of a Hook Selection File:

If the current plate thickness is 15 mm, the hook 101 is selected. If the current plate thickness is 10 mm, no hook will be selected and the warning:

"No hook found for this hole <type> <size>"

"Check hook selection file (SBH_HOOK_SELECTION)"

A special hook type "-2" is used to for holes that shall not be burnt, but instead marked with a special marking (see below).

Figure 3:4. Figure Showing Special Marking for Small Holes.

Alternatively such holes will be marked with a cross (see below) if the environment variable SBH_MARK_HOLE_CROSS is set to a real value. If the assigned value is greater than zero both arms of the cross will be drawn with the indicated length. Otherwise the arms will be extended to the hole contour.

Figure 3:5. Figure Showing Special Marking for Small Holes when SBH_MARK_HOLE_CROSS is defined.

The Hook Selection File is read already in the automatic part generation and the marking is created by this program. The produced sketch will also contain designation of the hole together with a text string defined in ppanparts.