I’m glad to hear Formlabs is still looking to improve packing features for SLS. I’ll share my approach to packing and give some feature requests at the end.
For random parts and prototyping I often use the auto-pack feature. It’s helpful when a job contains many different or oddly shaped parts.
For production runs I almost exclusively use manual packing. My typical workflow for this is to first define which orientations are acceptable for the main parts (many of my assemblies contain small components, like a lid/cover or bracket, and I save these until the end). If I have aesthetic features or sealing surfaces, I try and face these down or towards any wall. When these surfaces point up, even minor dimpling can compromise the function or appearance.
Next, I view from the top/bottom and move the main parts to get an idea of the best packing layout. Sometimes I lock XY orientation and use auto-pack on the first layer.
Once I know how I want to arrange the first layer, I typically use the array feature to ensure equal spacing. This is the only way to define a set manual part spacing, and one of the major shortcomings of manual packing in my opinion (see my post here for more information).
Sometimes parts fit conveniently with each other, and I always make sure to take advantages of these fits, as seen in the examples below.
Finally, once I’m happy with the packing of my main parts, I lock them, import my smaller parts, and auto-pack them. The highlighted parts in the image below were added in this last step.
I’m sure every user has a slightly different packing approach, but this process has worked well for me printing in Nylon 12. Other materials probably have other nuances to keep in mind. I know some users also like to keep a buffer around the walls or maintain a larger part spacing.
Feature Requests:
Model Spacing in Manual Packing
- I go into detail on this one in the post linked above
“Avoid Orientation” in Auto-packing.
- This one is difficult to explain, but I’ll give it a shot. I would be more likely to use auto-pack if I could define an orientation to avoid. In the image shown directly above, the highlighted part prints best when the flat surface points towards the chamber wall. There is no way to allow the part to pack in either of the acceptable orientations.
I’d be happy to jump on a 1:1 or answer any questions you have here!