Need help with Hole Replication please

[Golfer111]

Need some help from the knowledgeable members.
So trying to make a plasma cut sheet of steel with a swish cheese of holes. Purpose build. Not just for fun.

I’ve made it QCAD, add 72” L x 18” W
No problem. But, My question, is adding 1” Holes, all equally spaced, with 1” offset, all symmetrically laid out to maximize the footprint. Is there a trick Manually doing it, isn’t efficient and isn’t symmetrical.
Sorry for Newb question.

Like this.

[CVH]

Hi, and welcome to the QCAD forum,

Standard rasters like this can be defined in various ways.
By vertical spacing and the spacing between vertical rows.
By horizontal spacing and the spacing between horizontal rows.
Or by the spacing on a slanted row and the spacing between slanted rows.
The spacing can be seen as the spacing between the holes or between the centers of the holes.

Ideally the 6 holes surrounding a central hole lie on a circle and are all spaced evenly.
This means that they are positioned at 30-90-150-210-270-330°.
Or rotated at 0-60-120-180-240-300°.

An easy way is:
- Draw .. Circle .. Center, Diameter (CA) > In the Option Toolbar: Set diameter of hole, Angle don't care, Reference = Middle
Indicate a position for a central hole, a Grid point could be handy for the next step
- Draw .. Shape .. Polygon (Center, Corner) (PG1) > In the Option Toolbar: As Polyline, No fill, No radius, 6 corners.
Indicate the center of the central hole.
Indicate a point Y higher than this point, Y = hole diameter + inter-spacing between holes.
- Draw .. Circle .. Center, Diameter (CA) > Use previous options
Indicate the 6 corners of the polyline for 6 new circles.
- Select and delete the polyline.

This pattern can be repeated in any direction.
First expand this in the vertical direction (MV with multiple copies) to create 3 rows of holes.
Then expand this in the horizontal direction cloning 2 vertical rows at once with MV and multiple copies.

The full pattern can then be centered in the sheet for example.
Too many holes can be selected and deleted with a box selection.

Regards,
CVH