Pierce a dome at true size

WhereBlender’s top menu bar, File > Open, then File > Save As.

DoOpen p10-05-start.blend. Then choose File > Save As and give it a name of your own, so that the start file stays clean.

You should seeTwo smooth domes side by side, each 24 mm across and 5 mm high: a thin shell with a wall of 1.00 mm, hollow underneath, on a short upright foot 1.00 mm high. You use Dome first and Dome B near the end.

It worked whenThe 3D view shows the two domes and nothing else.

WhereThe sidebar at the right of the 3D view (press N with the pointer over the 3D view if it is shut), the CAD/CAM tab.

DoClick Flow in the section bar, the small word buttons. Then click the words Flow on Surface once to fold that panel: it shuts up to its title.

You should seeThe Pattern Builder panel, with Make Pattern in it (marked 1).

It worked whenYou can read Make Pattern without scrolling.

If it goes wrongYou cannot see Pattern Builder: the panel above it is open and takes the room. Click the words Flow on Surface once.

WhereThe 3D view.

DoClick once on the left-hand dome, on its near side.

You should seeAn orange outline round that dome.

It worked whenThe words at the top left of the 3D view end in “Dome”.

WhereThe 3D view, with the pointer over it.

DoPress Tab.

You should seeEdit Mode is where you work on one piece’s own faces, edges and points. The faces of the dome’s crown are already picked for you, and show orange. The lower part of the dome, near its foot, is not picked. The blue-green line round the foot is only how Blender draws a sharp edge.

It worked whenThe menu at the top left of the 3D view reads “Edit Mode”.

WhereThe Pattern Builder panel. You are still in Edit Mode.

DoPress Make Pattern.

You should seeHexagon posts on the crown, solid until Make Real cuts them. The guide lies in front of the dome: a flat round copy of the picked faces, with the same cells on it. It is no part of the piece. The blue marks and the word “Done” are handles: leave them alone for now. You may click Done when they get in your way. It may take a few seconds.

It worked whenThe panel’s line with the tick, which counts the cells, begins “55 cells”. The status bar says so too, but its message fades: the panel keeps the same figure.

WhereThe sidebar, the words Flow on Surface.

DoClick Flow on Surface to open that panel.

You should seeA little below the Make Guide button, a line that reads “Within 2.0 %, worst -3.1 %”. A dome will not lie flat, any more than orange peel will, so the guide cannot be true everywhere.

It worked whenYou can read that line on the panel.

WhereThe sidebar, the words Flow on Surface, then More Pattern Settings at the foot of the Pattern Builder panel.

DoClick Flow on Surface to fold it, then click More Pattern Settings to open it, and scroll down.

You should seeThe settings open below those words, so scroll down to the row “Land”. Land here means how a cell lands on the surface. Land Whole is lit: it is the add-on’s choice, and you keep it.

It worked whenLand Whole is the lit one.

WhereThe row Land, under More Pattern Settings.

DoPress Bend with Face, read the panel’s first line, then press Land Whole again.

You should seeThe panel’s first line goes to “61 cells” and back to “55 cells”. The pictures below show one hole cut through the middle with each choice. With Land Whole the hole’s walls run straight: 1.60 mm outside, 1.60 mm inside. With Bend with Face the walls lean in: 1.62 mm outside, 1.54 mm inside, and the cut makes 61 holes for 55.

It worked whenLand Whole is the lit one again.

WhereThe Pattern Builder panel, near its foot.

DoPress Make Real.

You should seeThe posts become holes, after a few seconds. Scroll up to Least Opening (mm): the new sentence, “Thinnest metal between openings”, stands below it, after the line about the rib. It gives the metal left between the holes, and the panel says openings for holes. It reads 0.47 mm on “the pattern’s face”, which is the outside, and 0.37 mm on “the far face”, which is the inside. The inside figure is the one that counts. Land Whole keeps every hole one size, and a rib, the bar of metal between two holes, pays for it.

It worked whenThe holes show on the dome, and the panel’s sentence begins “Thinnest metal between openings”. The status bar begins “Cut 121.2 mm3 from Dome” as well, for a few seconds.

WhereThe 3D view, with the pointer over it.

DoPress Ctrl+S. It saves the copy you named at step 1.

WhereBlender’s top menu bar, File > Open.

DoOpen p10-05-start.blend again. If Blender asks whether to save the changes, choose Don’t Save.

You should seeThe two whole domes again. Click Flow in the section bar if it is not lit, then click the words Flow on Surface once to fold that panel, as in step 2: Make Pattern shows on the panel. This time you use the right-hand dome.

It worked whenYou can read Make Pattern without scrolling.

WhereThe 3D view.

DoClick once on the right-hand dome, on its near side, then press Tab with the pointer over the 3D view.

You should seeThis time every outer face is picked, as in the picture, down the foot to the ground.

It worked whenThe words at the top left of the 3D view end in “Dome B”, and the menu reads “Edit Mode”.

WhereThe Pattern Builder panel.

DoPress Make Pattern.

You should seeThe posts cover the whole dome, over its shoulder and down the foot. Nothing has complained yet.

It worked whenThe panel’s line with the tick, which counts the cells, begins “121 cells”.

WhereThe Pattern Builder panel, near its foot.

DoThis press is refused, to show you a refusal caused by the form: the dome is not harmed. Press Make Real, then read the red words under Last message, lower on the panel.

You should seeAfter a few seconds Last message turns red. It begins “Not made real: Thinnest metal 0.01 mm through the wall”, then says “under its 0.25 minimum (the Thinnest Rib Allowed on the panel)”, offers a smaller cell, a wider rib or fewer cells, and ends “The piece is as it was.” The status bar says the same, but fades. Those offers are not the cause, as the next step shows.

It worked whenThe dome still has its posts and no holes.

WhereThe Pattern Builder panel, near its foot, then the 3D view.

DoPress Check Metal, then look level with the dome’s foot, as in the picture.

You should seeSmall red crosses where a cell comes down over the shoulder onto the foot: there the cut leaves almost no metal. The panel says “24 places under” the 0.25 minimum. To look level with the dome, click the green ball with no letter on the small coloured axes at the top right of the 3D view, and choose View > Frame Selected if the dome slips out of view. 12 of the 24 crosses stand on the foot nearest you. The 12 that seem to float high on the dome stand on the far side of the foot, seen through the metal.

It worked whenYou can point to the red crosses round the foot.