4 stars
Slices and integrates nicely with Prusa printers

Slic3r is an open source slicing program with the features you’d expect. The Prusa edition adds in some integration with Prusa printers to make program setup a bit easier.


UI is pretty and works well for common tasks. There are some menus and advanced features that are inscrutable until you go through the documentation. You have to manually keep track of which tab you are in. Parts only show up in 3D and 2D tabs until they have been sliced, then you can see more in preview and layers tabs. Settings are nicely laid out across 3 tabs at the top.


Everything works quickly and as expected.


Good piece of software made better with printer integration. Easy things are easy and hard things are possible(once you read the docs).

3 stars
Usable now, incredible potential

FreeCAD is a FOSS 3D parametric modeler that runs on Linux, Mac and Windows. This is a review of version 0.17.


Parametric modeling

Parametric modeling is the killer feature here. It allows you to link dimensions so they autoupdate when the parent changes. This is early software and it shows. Sketches mapped to faces will map themselves to a different plane when editing a feature above the sketch in the feature tree. You can also link dimensions by naming a dimension and then referencing it by name when creating another constraint: Sketch.constraints.name. This part is well thought out and easy to use. Datum features are new in this version and need work. I’ve spent several hours fighting to get the datum planes defined correctly even when doing simple things like creating a copy of the xy plane but higher on the z axis. That being said, once a part is modeled with datum planes and dimensions are controlled with named constraints, everything works well.


Sketcher is on par with commercial programs for the most part. I’ve had issues with auto constraints not always being applied which will cause issues when you try to base a feature on the sketch. The solver has issues that will lead you to overconstrain sketches if you follow its guidance. Fixes for this are already in the 0.18 branch.


Straight forward and relatively easy to use. It’s interface is similar to many other CAD programs with toolbars for commands and a feature tree for the part. The property view panel is a great addition that allows you to see all the properties of feature or sketch and edit them. The UI is confusing when multiple parts are open in seperate tabs because the feature tree keeps both parts in the same pane and doesn’t change focus when you switch tabs. This leads to many unintended edits on the part you can no longer see.

FreeCAD 0.17 (Own work. License: CC-BY-SA.)


Software is usable now with quirks that come with early development software. The majority of features of a true 3D parametric modeler seem to be in the program but many need work. Assemblies are not yet implemented… The ongoing development should make this software not only usable but competitive with commercial products in a few years.

5 stars
Great printer


i3 mk3 kit (Own work. License: CC-BY-SA.)

Kit arrives in box with several smaller boxes inside for the sub assemblies. Everything is well organized and labeled. The kit comes with tools for assembly, 1 kg of PLA and gummy bears. Assembly of the kit took around 12 hours and can be tedious. Be prepared to spend much more time than that if you aren’t experienced with this kind of work. Assembly instructions were generally good but, use the online version so you can see comments where people had trouble or the instructions were confusing. The tuning once the printer was assembled takes patience and is a bit unsettling. It has you do a pre-programmed print and adjust the z axis down while printing to calibrate extruder to print bed relation.

Assembled i3 mk3 (Own work. License: CC-BY-SA.)

I use Slic3r Prusa edition to create gcode for the machine. The integration is very well done with the defaults for the printer being loaded in automatically. Default settings have been turning out quality prints. PrintRun(pronterface) had no issue connecting to the machine and running prints.


Printing has been mainly simple parts in pla on the default 0.2mm fast profile with 20% to 80% infill. First layer is consistently good without a brim or raft. Some features have had small issues on the first layer where there’s sharp corners or tight radii, but they rarely cause issues with the overall print. Prints pop off the PEI sheet easily and if you have trouble the entire sheet can be removed and bent. PETG also prints without issue.


The printed printer parts, software and firmware are all getting continuous updates from Prusa Research. This makes me confident the machine will be well supported throughout its useful life.


Reliable machine that produces good prints. Well worth the money versus a cheaper machine in the time and frustration you’ll save.

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