The examples for the Digital Elevation Model (DEM) of Iceland have been generated using the QGIS (https://qgis.org/) plugin DEM to STL (https://plugins.qgis.org/plugins/DEMto3D/).

You can find a detailed guide here: https://opentopography.org/learn/3D_printing 

The model size is 528.52mmx381.04mm for a scale of 1:1'000'000. 
_nobase means the base has been set to 0 instead of 2mm. 
The default recommended spacing of 0.2mm is used.

The the settings_1x.png (https://ftp.lmi.is/stm/marco/DEM_3D_STL/Settings_x1.png) shows the settings used to create the model with 1x vertical exageration. 

To download the 3D model go to:
https://ftp.lmi.is/stm/marco/DEM_3D_STL/IslandsDEMv1.0_10x10m_isn93_zmasl_model_x1.stl

To download the 10m resolution DEM of Iceland go to:
https://ftp.lmi.is/gisdata/raster/IslandsDEMv1.0_10x10m_isn93_zmasl.tif

For more information of the QGIS plugin:
https://demto3d.com/ or https://plugins.qgis.org/plugins/DEMto3D/

License: 
CC4.0 - https://www.lmi.is/is/um-lmi/starfsemi/skilmalar-og-gjaldskra/gjaldskra

For questions:
lmi(hjá)lmi.is