So I believe I’ve solved the issue and it has to do with the model geometry as it’s converted into the STL file type from my modeling app (Rhino OSX) though I will print a different model using the same process to make sure.
In my experiments using MeshLab to check the model, I had been loading in OBJ files saved out from Rhino which didn’t give me any error messages when opened in MeshLab so I assumed that they were error free and ready to print. This time I saved out an STL from Rhino and then imported it into MeshLabs and it asked if I wanted to ‘unify duplicated vertexes’ I chose OK and then checked with the MeshLabs filters that there were no extra vertices or faces (both showed 0). I then re-saved the STL, imported it into the PreForm software and printed it again at the same 50 micron setting. The print this time came out flawless and actually much better than I had expected, especially for a ‘medium’ resolution setting. The small bits of deformation at the edge of the ring on the left are from the support structures, but I find that these sand off very easily. As for a scale reference, the orange grid on the matt is in 1" increments.
Nigel, thanks for referring the other posting showing the same issues, I’ll post a comment there regarding my findings.
So in summary (and I will double check this using the bracelet model that was having the same issues and will report back here)…
Export an STL from your modeling app, import it into MeshLab, OK the repair dialog when opening if it comes up, re-save the STL file and open in the PreForm software to print. MeshLab has a range of filters for cleaning and repairing meshes that you might play around with if you’re still experiencing these issues.
Maxim mentions in this post http://support.formlabs.com/entries/23992961-First-print-first-impressions that these defects (he’s referring to a strange layer shifting effect) are related to artifacts in the geometry and that they’re working on dealing with these geometry defects in upcoming PreForm builds. I also noticed in my initial prints that the support structures didn’t print clean either. Some supports looked weak and others had shifted mid way as though they were cut and moved at an angle. The models also had raised areas on the surface perfectly in line with some of the supports as though the support continued all the way through the model. After cleaning up the geometry in MeshLab however all of this disappeared and both the model and the supports printed perfectly.
Considering all the things that could go wrong in producing a print, I have to say that I’m INCREDIBLY impressed with the Form1 as a first product. Not only is the build quality insane, but to bring a precision product together with easy to use print software and a resin formulated to the machine is nothing short of impressive. Given the teams talent and dedication, I can only imagine that the experience will get better with time.
I initially wanted a printer I could use to refine my jewelry designs with before sending out a final file to be printed at a casting company, but instead I got a machine that will allow me to print the final forms to create the molds from at a resolution that looks like it will be indistinguishable from the Perfactory machines my casting company is using, especially after a little light sanding. A high-res print of a cuff bracelet at a casting company can cost anywhere from $500 - $1000 as they tend to charge by the hour for print time. At that rate, the printer practically pays for itself out of the box.
Hirudin, in celebration of the latest clean print, I’m going to have my wife make a cake while I do the next test. I’ll let you know how it comes out