THE ARCHITECTURE OF 3D PRINTING - 04 ENTOURAGE

[Stefania Dinea 101]

I am Stefania Dinea, an architect who mixes 3D printing, VR, parametric design and blogging daily and I will share some of my 3D printing tips & tricks with you. This series is my overview about the process and my work-around. Please feel free to comment and add. 

 

PREVIOUS POST:

THE ARCHITECTURE OF 3D PRINTING - 01 TOPOGRAPHY

THE ARCHITECTURE OF 3D PRINTING - 02 MASSING

THE ARCHITECTURE OF 3D PRINTING - 03 TOLERANCES AND SNUG FIT

 

04 ENTOURAGE

Basic entourage consists of the following: Human figures in scale, trees and vegetation, and vehicles.

 

So what would be the best approach to this? Especially when you are dealing with a sloped terrain – you also have to remember that super glue is your best friend but it does not always give out the best result in terms of optimal efficient solutions.  One of my tips is to place holes in the site (floor in revit) and make little support extensions/pins for your entourage of choice. So how thick should a pin be? Remember the 2 mm min thickness I was talking about? Well that would be it – 2mm in scale in 1:400 + offset of 0.3 mm. So in scale that should look like this:

Support system diameter:

Support placement diameter:

This is how the site looks like after perforation:

 

To do now entourage – one option would be to model in view, another would be to use a family to model specific entourage. One thing you cannot use are the families already included in Revit (unfortunately) specially when it comes to entourage.

 

To look for inspiration, there are multiple options, in terms of sketching, and as I said before, you are only limited y imagination. So to get started you might want to use the following keywords in your google search: people silhouettes and architecture tree sketches and you will find example such as:

 

 

So pick what suits your own project, your style and maybe you even have your own design. 

 

Now to continue with Revit, cut a section through one of the placements spots and insert and image of one of your desired human silhouettes once you have decided on one type and click on model in place.

The simplest way to go around things is to just trace and extrude.  and it might look bulky due to the scale you are working it – but remember that in the final print it will be quite small and fragile.

 

A perspective preview of the result:

I would print this item flat, however the issue is as follows:

If you check the top view, my base model might be problematic and my single extrusion is impossible. The solution is to alter the base.

 

If your model seems to thick and chinky, you might consider printing it on the side, and cut it in half.

Just look how small it is at scale 100% in Cura - it's a game of spot the model (it's the very small yellow dot in the middle )

(it's that very small yellow dot)

However, in scale 1:400 (250 in cura) it will look a lot bigger, not by much though.

After the first print with recommended Cura setting for extra fine I discovered that my 0.3 tollerence in Revit was too little.

 

 

So with these general dimensions in Cura, my print pin was just the exact fit of the diameter whole – therefore inadequate. To avoid going back to Revit and making alterations, I went for a modification in Cura.

As follows, by making sure that Uniform scaling is unchecked – in the end, the only thing of importance that needed rescaling was the diameter of the base and not the height.

 

Running a test print and seeing that this tolerance worked I remodeled the initial scalable human silhouette – and took if for another test print.

The same principle applies to modelling tress, you can make them as a flat 2D extrusion or a 3D volume.  In the image below are two examples:

For efficiency reasons I do recommend you model them as a family type, so you can reuse them in multiple projects. And I do recommend you make a parametric family so you can change the level of detail according to scale. But more on that in another blog.

For now I will print a little army of trees so my landscape will look something like this:

As you will notice in my final prints photos, I am not a patient person, and in this industry is hard to be, as everything is last minute and deliveries have a yesterday deadline on them. No matter how fast the machines are working if it's not instant it is never fast enough. However, please remember the time when everything had to be made by hand and delivery took forever on various materials needed to produce a model – I don't know about you, but I sure don't miss it – not to mention the cost. Nowadays time is generally consumed by 3D modelling – that is why I am a huge fan of BIM – if you have a proper BIM model, adding an extra as a 3D print should take no time at all to adjust, as you will see in the following chapters.

Also, how small can you print entourage?

 

 

NEXT ON THIS SERIES:

05 HIGH RESOLUTION BUILDING FACADES

 

human.stl

site for landscape.stl

tree1.stl

tree-2.stl

Edited May 26, 2018 by Stefania Dinea

[SandervG 1,521]

16 hours ago, Stefania Dinea said:

Also, how small can you print entourage?

 

Good question. I know we have some other architects around here. How small do you print the entourage you usually use in your projects?

Do you 3D print people / trees, or do you craft them in another way? What about vehicles?

 

And if so, do you print them white as well, or would you print the trees in green for example. Looking forward hearing what you do in your business! 

[Alex L 29]

Great post Stefania. Time to possibly make you jealous again. Archicad objects seem to be pretty 3d printer friendly.

Here is a 1:200 person, I wouldn't generally add people into a model any smaller than 1:200 as they tend to be for massing only. Trees are fair enough but people look a bit insignificant IMO.

 

Trees will also come out of archicad into Cura with no problem, although I haven't printed one out yet as I'm short of time.

 

Really looking forward to your post on facade detail.

[Stefania Dinea 101]

44 minutes ago, Alex L said:

Great post Stefania. Time to possibly make you jealous again.

 

@Alex L

.... NO COMMENT !

..ok just one:

I can't believe it !!! 

 

I am starting to really doubt Revit! However, it is a problematic software for 3D printing, so I guess my tips will be useful for some, and your valuable input very useful to the other side of the camp. Is that little human 3D printed on a UM? please share settings if yes. 

[Alex L 29]

Yeah, I'm starting to feel pretty glad that we are ArchiCAD based the more I experiment!

 

1 hour ago, Stefania Dinea said:

Is that little human 3D printed on a UM? please share settings if yes. 

Yes, he's an ArchiCAD object exported to Cura as a 1:200 .STL file. Printed as a fine model with PVA support, I think he would snap off without, not to mention the difficulties with the arms.

 

Here is the STL file if you want to have a play with it.

test human.stl

 

You can see the level of detail which is ignored by the printer. He could do with being stood on a plate or tower for proper integration into a model.

Edited May 3, 2018 by Alex L

[Stefania Dinea 101]

@Alex L awesome!!!

[SandervG 1,521]

That is small @Alex L ! Did you print that with a .25 print core or with a regular .4 print core / nozzle? 

Perhaps it could be useful to share some tips how you can print that small. Besides the tips from @Stefania Dinea what can you do to print good small prints?

 

If you want to print something that small it is usually recommended to print more than 1. Why? Because every layer you have extruded needs time to cool down. 

The filament is still hot and therefore somewhat saggy, and the nozzle is also hot. If you would print only 1, the next layer would continue to melt the previous one, and your model will end up beyond recognition probably. If you only need 1, you could consider to print a small pillar / tower next to it so your nozzle has to move from object A to object B. Make sure there is enough space in between the two models. 

 

It is also recommended to print with a .25mm nozzle or print core. With a .25mm print core, it is not recommended to also print very fine layer heights because the amount of filament you want to extrude would become so small this would be difficult to control through the bowden tube, and under extrusion could be expected. 0.1 layer height with a .25 mm print core would be a good starting point. So what do you gain? The nozzle size is mostly relevant for X and Y resolution. So when you would be printing a figurine, with a .25 print core you could probably detect facial features or details in clothes or details in vehicles parked. 

 

With a 0.4mm nozzle or print core, you can go down to 0.06mm layers. Which gives a smooth surface quality in Z, but is less suited for intricate details in X and Y. 

 

It is also recommended to print with low temperatures. Which exactly really depends on what filament you use, what speed you print at and what 3D printer you have. But generally, cooler than you are probably used to. 

 

These are the first tips that come to mind. Does anyone else have any more, perhaps from personal experience? Any settings you can share with your 3D printer / filament?

 

[Alex L 29]

This was printed (as were the tweezers) using the 0.4 print core. We have not yet tried using our 0.25 core.

 

This was printed with PVA support and using the 0.06 extra fine extrusion height.

I would imagine that this has helped twofold:

The pva allows for a greater structural support for the model reducing the risk of it distorting or breaking off the build plate whilst printing (as well as allowing the arms to be printed with relative ease)

The time take with each layer to print the PVA allows the previously laid plans time to cool without the need to print a purge tower or similar.

 

It is by no-means perfect, the resolution is pretty low at close inspection but if you are using this for context on a 1:200 model I don't you'd notice the fuzzy edges!

 

I might have to give him a go using our 0.25 core to see what difference that makes...

[SandervG 1,521]

That is still pretty good with a .4 print core. It's also a trade-off. If you are happy with this result for that size and time it takes to print, I'm not going to tell you to start using the .25 print core. If you ever need some better resolution, give it a try ? It will take a little bit longer and you'll have a more detailed print. It is a time - quality ratio. But if you have a .25 print core around, I would be curious to see what you will make of it and which of the two eventually would have your preference. 

 

Did you use the PVA as a raft? So it just lays on there? I could imagine that PVA is not that great with many retractions and on such a small scale it would need to retract a lot because it only needs to print small distances. 

[Alex L 29]

I did one with a PVA raft and one with the man stood up with the support structure wrapping around it. The support structure was much much bigger then the figure itself with a 6mm perimeter all around with no brim. |The PVA support ended up very messy but it did the job. I think if I printed this without the PVA I would certainly need a brim at the very least to stop it from falling over. Might give it a try without the PVA as it says it will only take 2 mins to print.

[SandervG 1,521]

Make sure to let us know how it came out ?

[SandervG 1,521]

In case you didn't see it yet, @Stefania Dinea  wrote another excellent guide ?

[SandervG 1,521]

On 5/8/2018 at 2:58 PM, Alex L said:

I might have to give him a go using our 0.25 core to see what difference that makes...

 

Did you ever give it a try?

[Alex L 29]

Not yet, I have been too afraid to open up the wrapper! Going to print out a core holder to put the .4 core in first!

 

[Edit, downloaded a core holder stl from thingiverse, watch this space!]

Edited June 4, 2018 by Alex L

[nallath 1,124]

It could also be an idea to just print groups of people as a single object. That way you have a bit more wiggle room.

Printing multiple small objects at once also improves the quality, as cooling is usually the biggest issue. With multiple tiny objects you provide the layers with enough time to cool before a new layer is cooled.

[Alex L 29]

Well here it is, 0.25core and printed without support but with a brim which provides a handy stand

 

You can see a difference in quality between the 0.25 and the 0.4 core used to do the original little human who looks a lot more like a mummy in comparison (he has also got a bit dusty sat on top of my monitor). Bear in mind that these are at 1:200 though so are really tiny at about 8mm high.

  

Edited June 20, 2018 by Alex L

[gr5 2,225]

Hi there @Alex L, I have printed even smaller people but you have to change a few things:

 

1) Print several at a time.  At least 5.  This way each one can cool while it's printing another.  Cooling is a problem when printing this small.  I like around 10.  Usually one falls over so I don't like to print too many as sometimes one can mess up a few others.

2) Lower the temp if using .25mm nozzle.  Try 190C or even 180C.  Don't go below 175C because if the temperature dips below 170C the feeder will not rotate (it's a feature - there is a way around this - see "cold extrude" - if you want to go lower).

3) Crank the fan at 100% although this is default anyway.

4) I like brim but your brim is bigger than needed.  Some of the people I printed had tiny feet and I adjust the brim so that it made a nice stand so they don't fall over when moving them around in my landscape.

 

I've printed 2cm tall people using 0.1mm nozzles and I'm very happy with them.