Cape Town to Cairo - 2D from the model

It doesn’t look like we will get proper linked 2D from the model anytime soon.
By that I mean not only 2D from the model, but the 2D being live, so changes in 2D also change the model.

I do think it a little shameful that in 2023 rhino is still very poor at this - a video provided by a poster at the beginning of the long thread in the V8 section “whats the plan” shows solidworks 2010 acing this problem - 2010!

On the other hand, there is something to be said, at least in projects involving only a few people, and of a scale of machines smaller than a ~ motorbike, or buildings no larger than a ~ single house, of taking a little more time and being a little more hands on.

Those of us who choose to work in rhino because of its many strengths in other areas, but who need to document the model in 2D have to manage somehow, and I’d be interested to hear how people are currently doing this.

We need to get the model to 2D in the most painless way possible.
What’s surprising is that doesn’t seem to be a problem for some much cheaper software.
For example, I still have a copy of viaCAD2D from 2010, which can import various 3D formats, including .3dm (V4) and instantly present the model in vector hidden line 2D, including the standard views and perspective.
Why can’t rhino do this itself internally…?

Interestingly, MOI3D , which is firmly within the Rhino family, being able to cut and paste back and forth, has an option, when exporting a model to a 2D format - including dxf - of saving out a vector 2D of which ever view of the model is chosen, with optional hidden lines on a separate layer.
This would obviously be possible in rhino, but is currently lacking.

Maybe its not seen as any different to the make2D command; however MOI also has this, but they also include the above.

Anyway, for now, and for the mechanical models I’m currently working with, I’ve found the key to making this work is the fact we can have multiple rhino instances open at once.

I have the master model, which is the full 3D model, and then usually if I’m sending out to laser cut / folding or 3D print a 2nd model which is cloned from the master, but organised by material.
This is because I order the files being exported for downstream by material and thickness - eg 3mm steel, 6mm steel, 6mm alloy etc

Then I have a third rhino instance which is 2D only, and contains all the sheet drawings and 2D extracted from the model. (I don’t find layouts to be at all helpful.)

This model has a series of empty “paper” sheets, A4, A3, A2 and A1 that have the title block , and all that kind of info in a grouped unit, and “floating” in a store to the side.

At the origin, I have a target rectangle of a size that can accept the whole 3D model, (or part of the model I’ll need to process), and this is labelled as 'Make 2D" in large letters.

So I start the process by alt+dragging a sheet from the store and placing it below and somewhere near the 2D target. I update the text on the title block to describe what it will contain, date, contact etc and then i alt + tab back to the working master, and select the first subsection of whatever part I am about to start with.
Then I copy a single part from the model and paste it into the 2D workspace.
From there I call the make 2D command, and drag the results onto or adjacent to the sheet.
I delete the model, so there is never any actual 3D parts in the 2D sheet model, (and no 2D in the master model) and then arrange the 2D appropriately.
I create a caption for it, which is formatted so as to contain the relevant information in the file name eg


DXF FILE: 6mmSteel_#01_070722
STP 3D FILE: n/a

The caption text is in a bright colour so I know I haven’t exported the file yet.
I then dimension the part, or usually just with the bounding box if its going to be laser cut. I check all the curves are closed, no stray overlaps etc and then group the part so it contains all floating curves like holes etc - the downstream software doesn’t care, and it means I don’t accidentally leave anything out.

I drag a clone of the same sheet adjacent to it, and continue the process until all the parts are documented in 2D on appropriate “paper” sheets , which stretch out across the screen in a number of rows as appropriate.

Then, I export each individual part unit to dxf, using the caption as the filename, and change the colour of the caption so I know its been dealt to.

After thats done, I note the number of the files in the directory I saved them to are the same as the number I have got on the sheets, and then, after composing a cover sheet, print to PDF, and zip the lot and send it off.

Using the same method, I also pull off the model any parts that are not going to be treated externally, and dimension these up in a similar way for fabrication / welding or other processing in house.

All in all this documentation process might take two to four days, and I’d typically have maybe 30 ~ 40 sheets when done.

I find it helps having the 2D completely separate in another file from the model, since it separates the two processes out, and a hiccup in one doesn’t spill over to the other, and of course the process will sometimes uncover something less than ideal in the model, which of course I fix as part of the process.

Several times in the last year I’ve been complimented by downstream personnel on the clearness and completeness of my documentation - in part I think because I am always thinking as I work if I had to build it with no background in the process, is there enough information?

I have a good friend who’s at the top of his field, and where specalised CAD software is typically used throughout the whole process; he prefers still to work with pencils and drawing instruments, and embraces the way his process will typically take two to three times as long as it otherwise would. He says that its good mentally to be not rushed, and to become very familiar with his decisions and process, so that downstream when the whole thing has to be put together under often huge pressure, he is pretty much all over it mentally and feels more connected to the final result.

I’d certainly like to see the 2D takeoff streamlined, but meantime especially for smaller projects its not necessarily totally terrible.
As it is, I could certainly do my work without Rhino, but just like I could actually walk from Cape Town to Cairo, I wouldn’t really want to do it…