Preform mesh load/display problems

Hi all,

I am having a little trouble loading some of my .stl models into preform. I am using PreForm1.8.1 on a late 2011 MacBook Pro running Yosemite10.10.1. When I load some models they do not display correctly, parts of the model are invisible, in some cases only a few layers are displayed. Here is an example:

If I look through the slices then the model looks okay. For example you can see in the following slice that the bottom right corner has been loaded somewhere in the software despite not rendering correctly in the 3D view:

I can orient the model, the 3D rendering is still not right but the slices are again okay. I suspect that if I tried to print at this stage it might be okay although I have not yet tried it. However, when I go to generate supports they are only generated for the parts of the model which are displaying correctly (looking through slices does not reveal any additional supports). For example:

Note that I have checked and repaired all models using netfabb basic before importing to preform so I don’t think there are any issues with the .stl mesh.
For some models I can get around this problem by exporting the mesh from the generating software with slightly different settings, however I cannot do this with all meshes.
I have also tried loading the stl into preform on a Windows PC (which loads and displays perfectly), generating a .form file, and then copying this file back to the mac (as the Windows PC is not near the printer). Viewing on the mac again doen’t display the model correctly although at least the supports are there and the slices appear okay. I am yet to try printing this to see if it comes out okay.
It is possibly worth mentioning that some of my meshes are quite large (100MB+) although I don’t think it is the memory issue as I have not had preform crash at all.

Has anyone else had similar issues or can suggest a fix?


Dont worry about this, Its only a Graphic display error that not affect to print.

That’s because your graphics card does not have enough memory to load the large objects and show you all polygons on display.

I have a good PC to design objects and generate the .form file. Also i have a Little one with 256Mb on graphic card and 4gb of main memory that has this problem, but prints perfectly all objects, I only use this little PC to print the object.

This issue only affects you if you use this PC to generate supports media and edit or manage object in Preform software, but just because you do not see everything on display. If it’s just only to load the object and print it, there is no problem.

Objects are not loaded into the VRAM.
VRAM is used for textures, not meshes.