making a hole in a Slab

[Anonymous]

I am novice in working with archicad, and I have a problem. I have to draw a spiral stairs from one Story to another. I have drown a Slab and I want to make a round whole through it for a stairs. Please, someone help me with this problem. Thank you.

[Achille Pavlidis]

welkome to Architalk... to make the hole its really easy...
1)draw a circle of the hole you want to make
2) select the slab
3) press the space bar
4) go on the circle, the cursor will turn into the magic wand
5) click... done

[Karl Ottenstein]

Welcome, too, Tonci. Good answer, Achille. I'm clarifying your instructions a little for Tonci:

Achille wrote:
welkome to Architalk... to make the hole its really easy...
1)draw a circle [or free-form shape] of the hole you want to make [using 2D tools at the proper location on the slab - and perhaps in a hidden line layer if you don't want to delete the linework after making the hole]
2) select the slab [and activate the slab tool if it is not active]
3) press the space bar. the cursor will turn into the magic wand
4) go on the circle [move the mouse to either an edge of the linework or inside the linework. If on the edge, the magic wand will turn black and the 'halo'/'sparkles' will change shape. If inside the space, you will not see a change in the icon]
5) click... done

Note, Tonci, that unless you created a perfect circle, the hole created will likely be polygonized. You can control how tightly the magic wand traces by going to Tools > Magic Wand Settings If you are not happy with the hole, just do an "Undo", change the magic wand settings to something more appropriate, and try again.

Have fun,
Karl

[Djordje]

Good explanation, Achille. This worked since always. In ArchiCAD 9 we have a direct way:

Make sure that the slab tool is in the Polygon mode.

Right click on the slab, Select and activate tool.

Draw the outline using PetPalette for getting the arc segments.

Done

Works for all the polygonal elements - slabs, roofs, meshes, fills, zones

[Ignacio Azpiazu]

Probably not for your situation (unless you have several spiral stairs), but thought I'd mention because it will be useful some day:

- You can select the hole in the slab by clicking on the hole edge, and then delete the hole or (trumpets) *multiply* the hole! This comes handy for making patterns such as say round glass block pavers in a concrete slab. Or when you have a spiral stair in each of the shops or apartments in a row, say. You can also select several holes and then multiply the group.

- If your holes are sprayed irregularly, you can always Drag and option+command to move around clicking and dropping duplicates of the hole/s you selected.

I mention this all the time after I once heard a friend working some 20 ft from me sounding honk-honk-honk-honk for about two minutes (he was making a sort of treillage by space-clicking on a multiplied grid of polygons -with multiply as a matrix he could have done that in a single operation).

[Anonymous]

Thank you all for your effort. The explanations were very helpful.