A new way to strengthen 3D prints has been released to PrusaSlicer and OrcaSlicer.
The method is called “Bricklayers”, and it’s a way to slightly alternate heights during extrusion. The idea is that if you simply extrude normally, the cylindrically shaped extrusions will have a gap between them as the curves intersect.
The Bricklayer approach is to alternate the heights so that the gaps are minimized, much like you would do when laying bricks. The image at the top shows how this works. This makes the print quite a bit stronger with only a slicing change.
Bricklayers was developed by Roman Tenger of Tenger Tech. His company previously developed the “Fuzzyficator”, another slicer add-on that can produce fuzzy skin more surfaces.
https://www.fabbaloo.com/news/fuzzyficator-update-seamless-integration-with-major-3d-slicing-software
The news is that Bricklayers now has a script that, when executed, installs the feature directly into OrcaSlicer and PrusaSlicer, making it convenient to use. Tenger explains how to set it up in this video:
If you watched the entire video, you’ll note there are some complications here. While Tenger has released the software on GitHub using an open source license, it turns out there may be patent holders involved in this method.
Tenger identified a long-expired US patent from Stratasys (from 1995) that describes pretty much the same thing. This expired after twenty years, so Bricklayers is in the clear.
However, there is also a more recent US patent from ADDMAN Group called “3D printing bead configuration”. This patent was approved in 2020 and is expected to expire in 2040. There is also a corresponding European patent for this.
The US patent’s abstract is as follows:
“The present invention provides a method for altering the bead profile for using 3D printing to improve the shear strength of a so-manufactured product by altering the bead height of adjacent beads or in adjacent layers such that either the height or the centers of the beads between adjacent layers are altered. This is achieved by either height reduction or by flow rates to alter the height or positioning of the beads by altering the bead profiles, the shear strength between adjacent layers in the X-Y plane is improved. The present invention is equally applicable to increasing shear strength in the Y-Z plane or the X-Z plane as desired.”
Yes, this appears to be precisely what Bricklayers is doing.
How can Tenger release the software if it violates the patent? It turns out the European patent has not yet been granted! It’s currently marked as “pending”. Tenger, based in Europe, takes this to mean that it is not currently patented in Europe, leaving him free to release the software.
There’s also the question of whether a patent can be granted for a method that was previously patented and expired. If that approach were allowed, a patent owner could re-patent their expired patents and keep them indefinitely. Perhaps this is why the European patent is pending.
Can you use the patented approach commercially? It turns out that you might be able to. In my discussions with ADDMAN, I learned that they don’t really have the software chops to implement the methods they’ve patented. They instead partnered with Danish company Create it REAL, a company that builds custom 3D print slicers, to perform the implementation. We first heard about their implementation a couple of years ago when they began to show the power of this method in their REALvision Pro product.
In this situation, there are things we know and things we don’t know:
- We know the method does work and provides much greater part strength.
- We know Tenger Tech has released an open-source version, Bricklayers, that can be used by the public.
- We know that a commercial implementation exists in REALvision Pro.
- We do not know how the patent complications will turn out.
It may be that Bricklayers could disappear from public repositories if legal action is initiated by the patent holder, ADDMAN Group.
Until that happens, I am pretty sure a great many 3D printer operators will take advantage of this capability.
Via GitHub, ADDMAN Group, and Create it REAL
