Open your Layers panel. That — not the Make2D dialogue — is where your drawings are won or lost. Make2D does exactly what you ask of it, every time, with no opinions of its own. The mess you get back is a model that was never structured for extraction: thousands of curves dumped onto a handful of generic layers, with nothing in the output telling you which line is a cut wall and which is the edge of a handrail. So you retrace it in CAD, and conclude the tool is rubbish.
It isn't. But almost every decision that determines whether the output is drawable happens before you type M-A-K-E-2-D. Here's the sequence that gets you from model to finished drawing — and, at the end, the two situations where Make2D is the wrong tool and you should stop using it.
Your Model Is Already a Drawing Set, Whether You Meant It or Not
Make2D has an option to keep your source layers. Tick it and the output inherits the structure of the model. Which means the output is exactly as organised as the input was, and no more.
So the layer tree has to do two jobs at once: hold the 3D model sensibly, and sort the 2D output into things you can assign a line weight to. In practice that means organising by level and by element, with the same sublayer names used consistently under every parent. Lower level, upper level, roof — and under each, walls, slabs, glazing, structure, joinery. Boring, repetitive, identical all the way down. The repetition is the point. Later you're going to type a word into the layer filter box and have Rhino select every layer that contains it in one go, and that only works if you named things the same way every time.
Two bits of geometry hygiene matter as much as the layers:
Set your units and absolute tolerance at the start of the file, not halfway through. Changing tolerance later doesn't retrospectively fix curves that were built loose — it just changes how the next operation behaves. Whatever your template handed you, go and look at it in Document Properties before you model anything, and keep a millimetre file in millimetres.
And build closed solids where you can. Coplanar faces sitting on top of each other — a slab modelled twice because you extruded the floor and then extruded the ceiling of the room below — give you two identical lines in the output and no way to tell them apart. Make2D is honest about your geometry in a way that rendered views never are. A render will happily hide a sloppy junction behind a shadow. A hidden-line extraction will draw it.
Blocks Collapse Everything You Carefully Sorted
This one costs people an afternoon. When geometry lives inside a block, the Make2D output tends to come back on the block's layer, not on the layers the geometry had inside the block definition. A beautifully organised chair with eight sublayers becomes one lump of curves on "Furniture".
For furniture that's usually fine — you want the chair on one layer anyway. For a block you're using to repeat a structural bay or a facade module, it is not fine, because you've just lost the distinction between mullion and glass across the entire elevation.
What we've found works: keep blocks for repeated things you'll never need to differentiate in 2D, and explode — or use a block whose internal layers you've accepted as the output layers — for anything that needs separate line weights. Decide this before you've placed two hundred instances.
Parallel, Named, and Square to the World
A Make2D from a perspective viewport gives you a perspective drawing. Obvious when you say it, infuriating when you discover it after a four-minute calculation on a large model.
Set the viewport to parallel projection. Use the standard Top, Front, Right views for your plans and elevations, and then save each one as a Named View with a name that tells you what it is — Elevation North, Section AA, Plan L01. Named views are not a luxury here. They're what makes the extraction repeatable when the model changes and you have to do the whole set again next Thursday.
The trap with elevations: if the building isn't aligned to the world axes, Front and Right give you oblique views of nothing in particular. Either rotate the model to sit square to the world at the very beginning — which is almost always the right answer for an orthogonal building — or set a construction plane on the facade you want and save a named view looking perpendicular to it. Doing this at the start is five seconds. Doing it after you've modelled the site is an afternoon of repositioning everything that was snapped to the old position.
A Clipping Plane Is Infinite, and It Only Cuts What You Tell It To
The rectangle you draw when you run ClippingPlane is annotation. The actual plane it represents is infinite, so the size and position of that rectangle in the XY sense doesn't matter at all. What matters is its height, or in the case of a section, its orientation.
For a plan, make the clipping plane horizontal and set its Z coordinate to the cut height you want — say 1.2m above the finished floor of that storey, which keeps you above the sills and below the heads on most buildings. For a section, make it vertical and position it where you want the cut. Then flip it if you're looking at the wrong half; the plane cuts away everything on one side, and which side is a property you can reverse.
The bit that saves real time: select the clipping plane, open Properties, and go to its own clipping plane tab. There's a list of viewports with checkboxes. A plane only clips the viewports you tick. Which means you can have a plan cut, a long section and a cross section all live in the same file at the same time, each one clipping only its own named view, and none of them interfering with the elevations. Set that up once and you can cycle through named views and fire off the whole drawing set in one session instead of rebuilding the cut every time.
The Three Settings That Decide Whether the Output Is Drawable
Run Make2D with the right view active and the geometry you want selected. In the dialogue — and the layout of this dialogue has shifted between Rhino versions, so read yours rather than hunting for a box in the position I describe — three things matter more than everything else combined.
Tangent edges. If this is ticked, untick it. Tangent edges are the seams where two smoothly joined surfaces meet — the line down the middle of a fillet, the join in a curved wall. They are not edges a draughtsman would ever draw, and they are the single biggest source of "why is there a line across the middle of my column."
Maintain source layers. Tick it. Without it, everything comes back on a few generic output layers and you are back to sorting by eye. With it, the output sits in a structure that mirrors your model, and your three-pass line weight job becomes possible.
View you're drawing from. Current view, not world top, unless you genuinely want a world plan. If you've set up named views properly this is a non-issue, but it's the setting that produces a mysteriously rotated drawing when you get it wrong.
Hidden lines are worth generating even if you don't plan to show them — they come out on their own layer, and it costs nothing to turn that layer off. Having them available when you need to show a roof overhang or the swing of a door above is better than re-running the whole thing.
The First Five Minutes After It Finishes
The output lands at the world origin, flat on the CPlane, which on a plan extraction means directly on top of the model it came from. Move it. Now, before you click anywhere else — because once you've deselected it, pulling that curve set back out of the 3D geometry is a genuinely tedious job.
Then, in this order:
SelDup, then Delete. Make2D produces duplicate curves wherever two coplanar surfaces meet. Killing them first means everything after this is working on half the data.
SelShortCrv. Picks up the slivers — the two-millimetre fragments at intersections that will plague you in Illustrator. Give it a length threshold sensible for your scale and look at what it selects before deleting.
Join. Turns the thousands of segments into continuous polylines, which is what makes the file workable downstream — you can select a whole wall edge with one click instead of forty.
SimplifyCrv. Converts arc-like runs of segments back into actual arcs. This is the command that rescues curved geometry. A double-curved facade or a spiral stair arrives from Make2D as a storm of short segments, and SimplifyCrv puts a lot of that back together. It won't fix everything — see the last section for what to do when it doesn't.
Line Weights, in Three Passes Instead of Thirty
This is where the naming discipline pays. Select your top-level output layers, right-click, expand sublayers — all of them at once rather than clicking thirty arrows.
Now use the filter box at the top of the Layers panel. Type a word that appears in one class of layer names and Rhino shows you every layer containing it. Select them all, set the print width once, and it applies to the lot. Three passes does an entire drawing: one for cut lines, one for everything visible beyond the cut, one for hidden. As a rule of thumb, cut gets your heaviest weight, visible geometry something like half that, hidden lines thinner again and on a dashed linetype. You can set linetype in the same pass.
For export: a PDF printed from a Rhino layout carries the print widths through as real weights, and opens in Illustrator with the structure intact — this is what we'd reach for when the drawing is going into a presentation set. For CAD, export DWG and pay attention to which export scheme you pick, because the schemes differ in whether they write true curves or tessellate everything into polylines. Export a small test piece, open it in CAD, and check an arc before you send the whole set. The schemes vary between Rhino versions and between what your consultant's CAD will accept.
When Make2D Is the Wrong Tool
Two situations. Know them and you'll stop losing days.
You only want the cut. The Section command run on your geometry gives you the intersection curves directly — clean, closed, properly curved where the geometry is curved, no hidden-line calculation at all, and effectively instant. For a model where all you need is the outline of what the plane passes through, Section beats Make2D comprehensively. The hybrid is better still: run Section for your cut lines, then run a clipped Make2D for everything visible beyond the cut, and put the two on separate layers. You get mathematically clean cut curves and a proper hidden-line background. It's two steps instead of one, and it is the workflow I'd default to for any section with curved geometry in the cut plane.
The model is too big. Make2D has to compute every edge against every surface, and on a full building with imported furniture and a site mesh it will sit there for a long time, or stop sitting there in a less helpful way. Don't run it on the whole model. Hide or lock everything the view doesn't need, select only what's visible, and extract in passes — building shell in one pass, furniture in another, site in a third — onto layers you've already named. It's faster, it survives a crash better, and when you only need to reissue the furniture layout you re-run one pass instead of all of it.
The thing worth internalising is that none of this is a Make2D technique. It's a modelling habit. Layers named the same way every time, geometry built closed and square to the world, views saved rather than hunted for, clipping planes assigned to the viewports that need them. Do that from the first curve and the drawings fall out of the model. Do it afterwards and you'll retrace everything in CAD, same as always, and tell everyone Rhino can't do drawings.
It can. It just needs you to have decided what the drawing is before you built the thing.
