Tabletop planning

BPR Architects have discovered that 3D printing building models can be of real benefit to their design team, encouraging them to explore their work in greater depth

Architects are not short of ways in which they can develop design concepts, and to involve their staff and other members of the design team in the process, sharing ideas and putting forward proposals, testing hypotheses and exploring solutions. These can range from informal tabletop discussions sketching out ideas, to formal Powerpoint presentations, to using the latest digital technology to build 3D models using augmented reality, image capture, artificial intelligence and advanced rendering techniques to produce high quality images, videos and walkthroughs.

Faced with such a wealth of technological capability, you might assume that the construction of physical small-scale project models has had its day, and that clients are more impressed by being able to explore virtual constructions of their aspirations. You would, however, be wrong.

I recently spoke to Paul Beaty-Pownall, the MD of BPR Architects about his acquisition, a couple of years ago, of a 3D printer, which was initially purchased as a device for presenting some of his projects to clients. Paul found, however, that the benefits of the technology were more evident to his staff. He had always had a gut feeling that 3D printing would prove to be a good way of exploring design ideas - and he was right.

The experience of standing over a table with a model laid out on it which allows a design team to see how a project looks and how it relates to surrounding buildings, whether they are part of the existing project or the urban area in which they are to be placed, allows everybody, Paul says, the time to absorb the different features of a project and to think about them in depth. He contrasted that with the way in which they would be shown as part of a Powerpoint presentation. There, he says, whoever was in control of the mouse would also have control of the meeting and drawings.

A tabletop 3D model allows each design team member to linger over the features they think most significant, enabling them to go back and refresh their visual and tactile memories at any stage of the design process. Paul and I agree on that point. Being able to handle model elements is as important as being able to see them. The hand reinforces what the eye sees. Model users can also experiment more easily with different element placings and sizes, moving them around or substituting them at will.

Although all model elements can be created directly from AEC CAD software, there are no constraints about adding buildings made from cardboard or plywood. These are just as easily added from 3D printed mass models - and no more expensive to produce.

The printer that Paul bought is an Ultimaker 3 FFF (Fused Filament Fabrication) available through GoPrint3D. It works by feeding a coloured filament through a heated printing nozzle, building up a 215 x 215 x 200mm max volume 3D component from the 3D model, taking between 8 to 15 hours per model. It uses an open filament system: 3D Print nylon, ABS, PLA, PVA and third-party filaments. It's not a fast printer, but can be used in dead time or run overnight.

The time taken is really immaterial in terms of the average time it takes to create a model for a client. Project owners would probably be disconcerted to discover that the design of an iconic building which they are investing heavily in was knocked up in the space of a couple of design sessions. The cost of 3D printing is also of small importance - the price of a replacement filament cartridge readily absorbed in the design expenses and not, Paul says, passed on to the client.

Printing the models from Vectorworks, Paul’s software of choice, is straightforward. There are a number of things that have to be considered though, and which Paul said became evident as they learned to use the printer. The accuracy of the printed components is quite good for design exploration purposes, but not for creating high quality display models for the client or public presentations. Let's put that in a bit more perspective. The client will benefit from the same facility that the design team have and can see how a project would look in general, and make suggestions for the placement of buildings - but populating the model with small-scale trees, street furniture and scaled people is probably a bit beyond it. Because of the difficulty of printing very thin components, some of the model layers have to be switched off. An example of this is a shop façade with large glass areas which would be unsuccessfully attempted by the printer. With the windows layer switched off, the printer would merely print the mullions and frames instead.

The same problem occurs with the internal plans of buildings where, because of the scale, some of the walls and partitions are too thin to be printed, and have to be modified within the printable version of the model.

If you want to 3D print a five storey building, the most effective way to do it would be to print it as separate storeys and to rebuild the model as separate parts. Additional problems occur when walls, say, extend below ground level, or incorporate some other unconventional element within the design. Paul says that the architect must be involved in making decisions that affect the modification of a design to suit the creation of its 3D model.

Once the precise 3D printed component has been defined, Vectorworks can be used to convert the file to STL format - the standard printing mode for 3D printing technology.

Numerous other benefits have increased the enjoyment with which members of Paul's team have approached 3D printing. Although it only represents about 10% of the projects that the practice is working on, the evidence of the work being done is spread throughout the office, rather than being hidden away inside individual workstations, project files or the architects' heads. The models are placed in cabinets, on window sills, and spare corners of desks, enabling everybody to see what other architects and designers are working on, and giving them a greater appreciation of the work their colleagues are involved in. It might also encourage them to contribute some of their own ideas.

The staff at BPR Architects are excited by the technology, and the only thing that prevents them using it more is its appropriateness for different projects and the limited opportunities that allow them to take advantage of it. BIM-rich projects require digital technology throughout to manage the large amounts of data that they generate, but even they will have started out as mass modelled concepts reliant on the basic modelling skills of the architect.

BPR Architects bought their 3D printer from a local supplier, who provided initial training and support, which, because of the simplicity of 3D printing technology, amounted to little more than ironing out initial fingers and thumbs problems - like having to sort out tangled fibre feeds and other basic mechanical problems.