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Printing with light-touch supports (Form 3/Form 3B))

Supports are essential in SLA 3D printing, but they require removal and often leave marks behind. Our new Low Force Stereolithography (LFS) technology works in combination with a smaller laser spot size to allow the Form 3/Form 3B to print parts with a new support structure that is easier to remove. These redesigned supports provide all the additional stability of regular supports without the long post-processing time.

The term "light-touch supports" refers to the various and ongoing changes made to the support structure on all Form 3/3B printers. Each resin has a unique support geometry that is specifically tailored for that resin's application, such as light-touch supports for Castable Wax Resin.

Note:

Starting with PreForm 3.5, all parts printed on the Form 3/Form 3B have light-touch supports.

A shot of the Form 2 support structure shows how the the scaffolding consists of many cross-links close to the surface of the part.

A shot of the Form 3 support structure shows how the scaffolding consists of mostly verticals without cross-links close to the surface of the part.

Left: Support structure for Grey Resin on the Form 2.

Right: Support structure for Grey Resin on the Form 3.

Redesigning the support structure

PreForm generates supports that are cross-linked together for increased strength and adhesion. On the Form 2, this cross-linking fills the entire space between the raft and the printed part, resulting in a uniformly rigid support structure. Because the support structure is equally strong everywhere, it can break unpredictably during removal.

The peel forces of the Form 3/Form 3B are significantly lower than those of the Form 2. As a result, the support structure does not need to be as robust at every point. The redesign takes full advantage of these lower forces to decrease both the touchpoint size and amount of cross-linking so that supports are easier to remove by hand. Any pressure you apply to the print as you tear the part away from the supports is now only distributed along the support touchpoints.

The following improvements have been made to the Form 3/Form 3B support structure:

More flexible scaffolding
A stiffer, more rigid raft
Smaller, more narrow support touchpoints
Stronger cross-linking within the scaffolding to hold the entire support structure together against outside pressure
Support sections near the printed part do not have cross-linking, allowing them to flex when pressure is applied
The combination of stiffness within the scaffolding and flexibility close to the support touchpoints creates a clean break along the part’s surface

A close-up magnification shot of the touchpoint size on the Form 2, which is nearly the same size as the scaffolding.

A close-up magnification shot of the touchpoint size on the Form 3, which is significantly more narrowe than the scaffolding.

Left: Larger touchpoint size in Grey Resin on the Form 2.

Right: Smaller touchpoint size in Grey Resin on the Form 3.

Removing supports comparison

When tearing supports away by hand, the redesigned support structure on the Form 3/Form 3B leaves significantly less material behind.

Profilometer scan of part removal shows varying shades of red and orange to highlight the large size of support marks left behind by the Form 2 support structure.

Profilometer scan of part removal shows shades of yellow and green to highlight the small size of support marks left behind by the Form 3 support structure

Left: Profilometer scan of material remains after part removal on the Form 2.

Right: Profilometer scan of material remains after part removal on the Form 3/Form 3B.

Additional resources