PrusaSlicer 2.2.0-alpha4

PrusaSlicer PrusaSlicer 2.2.0-alpha4

Summary

This is a third public PrusaSlicer 2.2.0 alpha release, following the alpha2 ↗ release (alpha3 was internal only). We consider this alpha to be feature complete to be followed by a beta release soon.

This release introduces hollowing and hole drilling in the SLA mode, improves the Color Print usability on MMU printers, introduces free camera rotation, moving / rotating of objects using cursor keys, predictable sequential print order with in 3D scene labels, Vase Mode improvements, fist Raspberry PI 4 builds, AstroBox integration and Dutch translation. This release fixes many bugs as well.

Please see change logs of previous alphas (alpha1 ↗ and alpha2 ↗) for a full list of new features and bug fixes in the 2.2.0 series.

To let you enjoy the alpha without worries, the alpha builds save their profiles into PrusaSlicer-alpha directory, so you may use the alpha side by side with the current release without ruining your production configuration.

SLA Hollowing

Hollowing a model and drilling holes to drain resin is a very important feature that helps save material and also lowers surface area of the model slice, hence it decreases the force needed to detach the print from the display when moving to the next layer. Until now, users had to do the model hollowing in a 3rd party software and import the result in PrusaSlicer. Since this release, the hollowing has been integrated into PrusaSlicer directly. (#2054, #3219)

The model hollowing is configured with the following parameters:

• Hollowing thickness - thickness of the resulting shell
• Hollowing accuracy - a trade off between accuracy and performance. If a low hollowing accuracy is set, accuracy of the resulting model thickness may suffer, therefore a higher hollowing accuracy is recommended for a small hollowing thickness (for thin shells) to ensure minimum wall thickness.
• Hollowing closing distance - Hollowing supresses cavities narrower than the closing distance threshold, and it also fills in sharp concave corners of inner wall, from which it would otherwise be difficult to remove the uncured highly viscous resin.

Hollowing can be configured either in Print Settings, or in the new 'Hollowing' gizmo, which allows to set the parameters on per-object basis: froghollowgizmo

The clipping plane tool, which is used to peek inside an object at the SLA support points editing gizmo is newly available at the SLA hollowing gizmo as well, and it is especially useful to review the hollowed geometry and to place the drainage holes.

As for the drainage holes, they can be placed by direct clicking on the object when the SLA hollowing gizmo is active. The holes can later be re-positioned by dragging them on the mesh. Each hole is always perpendicular to the surface and its diameter and depth can be configured (each hole can be different).

The hollowing and hole-drilling is performed after the Preview hollowed and drilled model button is pressed. Note that both hollowing and hole-drilling are computationally expensive tasks and the drilling will take some time, especially with complex models. In case the user does not press the button himself, the hollowing and drilling will be performed during the slicing process.

Please understand that if the input mesh is broken, the hole drilling algorithm may refuse to proceed to prevent program crashes or incorrect results.

Once the calculation of the hollowing and hole drilling finishes (whether triggered through the gizmo or though slicing), the hollowed and drilled mesh shows up in the 3D scene. The hollowed and drilled model is therefore also available in the SLA support point editing gizmo, allowing user to place support points inside the cavity and into the holes: frogsupportsgizmo

In case some parameter is changed that forces invalidation of the mesh (such as moving a hole, scaling the object, etc.), the model visualization reverts to the original object without the holes drilled and without the hollowing applied.

Important: There is currently no check that manipulation with the holes does not interfere with support points already placed on the mesh. For example, placing a support point and later drilling hole at its location results in a support point floating in mid-air. Similarly, drilling a hole, placing a point inside it and later (re)moving the hole results in a support point embedded in the object. Checks for these scenarios will be added in the next release.

The hollowing and hole drilling features rely on OpenVDB ↗ and CGAL ↗ libraries. Many thanks to the authors of the two libraries.

Colorprint improvements

PrusaSlicer2.2.0-alpha1 ↗ added support for colorprint in multimaterial mode, as well as a possibility to add pauses or custom G-codes. To make the feature easier and more intuitive to use, clear distinction has now been made between color-changes (user changes the filament manually) and extruder-changes (the filament is exchanged automatically, possibly using a wipe-tower). PrusaSlicer now supports the following three scenarios: