Optimising part for printing in full colour

Hi there everyone,

I am not a sketch up user (my background is in product design and I am more familiar with CAD software like solidworks). I am the studio manager at a Fablab based in Aberdeen and we have a full colour 3D printer. I have been on the look out for a good quality architectural model in colour and came across a few good sketch up based models. Only problem is these files aren’t print ready and I don’t know how to clean up these files and make them water tight and print ready. Does anyone have experience with this? Ideally I would love to make this file work…

Look forward to hearing back!


I would be more than happy to try and help you … First of all, how large is the final print you’re thinking about? Are you planning on printing this house as a “solid block” with the textures on the outside? Or do you want the inside to be printed as well (i.e., leaving a window or door open to allow removal of the inside fill)? If so, what is the minimal free wall (or wire) thickness for your printer? Is this a gypsum-style inkjet printer? Or maybe you could share the make and model of the printer as well?

Hi Jimhaml,

Firstly, thank you for your reply and for helping me out! This is indeed a gypsum style inkjet printer, specifically the Projet 460plus. The print volume is around 200x200x250mm and I would be keen to print this fairly large as it will be a display piece to try and show off the technology, so potentially 200mm in it’s largest dimension (however that translates to the model). Or in fact at a suitable scale for the building that would fit within the print volume.

minimum wall thickness for load bearing areas is 3mm however if certain features are smaller than that (i.e. outdoor staircase) then that’s probably ok. I am not interested in the internals, just a good representation of the outside with colour intact. I have tested an export from sketch up to .wrl and it imports with colour to our printer so exporting shouldn’t be an issue.

I would of course be happy to post as many pics of the result to you to show you how the model came out!


Sorry, should have added, I am only interested in the main building itself, not the superficial buildings around it or any of the roads/garden as I will be laser cutting a topological map for the house to sit on

Take a look at this CadSpan video…

they made one of the first SU to 3d printing plugins and it specialised in powder printing buildings…


Hi John,

I had a look around for a plugin, but they all seem to export as STLs which is not what I am looking for as I am looking to print in colour and the STL format doesn’t do colour. Or does this plugin

Cheers though

I’ve taken a look at the model and dissected it … the two halves are mirror images and could easily be printed separately and joined with a separate wall between them. When scaled down to 250mm in the long direction (not including the stairs), 2mm thick supported walls and 3mm thick unsupported ceiling/roof look fairly reasonable. You should be able to print the inside as well, with some modifications. Do you have a need to print this in one piece? If not, you could have a removable roof to see the inside details as well as a removable second floor for viewing. However, unless you have clear material (maybe invisible ink?), I’m not sure what you plan to do about the windows and doors.

Awesome, thanks for taking a look. I would be a little cautious about printing it with an interior too as we need to soak the model in a colourbond solution post print to bring out the colour. Also, cleaning the part up post print would be quite difficult if there were a lot of small parts (the prints are very fragile and we use compressed air to remove unused powder). I would be willing to try this at some point but ideally for now it would be great to just get an exterior model.

And you’re right it is just mirror imaged so might make sense to focus on one and then just mirror it and combine pre print (I am happy to do this as can edit .obj’s quite happily), it’s just working in sketch up that is an unknown to me.

If I was to print this with the interior, I would remove the windows and simply laser cut them from clear acrylic and glue them in place. I could actually laser cut the window frames too from laser ply too. Would be a little nervous about the unsupported overhangs though this would introduce.

Happy to work with you on this one if you’re up for doing the interior too. I had just imaged an exterior model myself.

Thanks again

This should be something you can start with … I removed all the colors and textures so you will have to apply those. The model has four parts:

(1) Right Half
(2) Left Half
(3) Dividing Wall
(4) Credits (not intended to be 3D printable)

My experience has been that you can just leave the three components as they are … the slicer will figure it out since each are independently considered a solid. BTW, the native DAE file output from SketchUp will allow you to specify colors and textures (I’ve used this for 3D color printing many times).

house.skp (118.7 KB)

Hi jimhami,

Thank you so much for this, this looks fantastic. I am happy to look into applying textures/colour maps myself and I will look into taking measurements for the windows to laser cut windows. I might try and edit the stairs back to something closer to the original as they look a little blocky there. I can laser cut the supports for the stairs and maybe print individual blocks for the stairs and bond them in place.

This looks really great though, how did you go about processing the model to make it a solid body?

I worked backward from your maximum print size and first scaled the model to size. Then I created a footprint of the right-half of the model 200mm to the right and extruded it to make a base. Then I began by tracing around the original model and transferred the floor plan to my draft model. I think 2mm walls would have been okay, but due to your concern about fragility, I used 3mm offsets in 2D for the walls and then extruded them upwards. The second-floor / first-floor ceiling was traced from the original and then added to the draft. Extruding that gave me the second-floor to which the traced outline of the walls was again transferred to the draft and extruded. The roof was added the same way as the second floor and some slight tidying up was all that was needed. The right half was then mirrored and the dividing wall added between them. I finally deleted the original model and moved my draft 200mm back to the origin. Ending up with the entire right half as a single solid was not necessary, but possible.

In practice, all you need is to create a slab as one component, an extruded floor-plan as another component, and the ceiling/roof as a third component. There is no need to merge them as long as each is a solid within its own context.

Making each of these as separate groups/components simplifies the “solid” process and also makes it much simpler to edit them later since they don’t interact with each other. When put together and printed, they will be one piece.

house2.skp (44.1 KB)