Techniques for surface preparation during additive fabrication and related systems and methods
According to some aspects, an additive fabrication device is provided configured to form layers of material on a build platform, each layer of material being formed so as to contact a container in addition to the build platform and/or a previously formed layer of material. The additive fabrication device may comprise a container and a wiper, wherein the wiper comprises a wiper arm and a wiper blade coupled to said wiper arm using a pivoting coupling.
1. An additive fabrication device configured to form layers of material on a build platform, each layer of material being formed so as to contact a container in addition to the build platform and/or a previously formed layer of material, the additive fabrication device comprising:
a container; and
a wiper, the wiper comprising:
a wiper arm; and
a wiper blade coupled to said wiper arm via a pivoting coupling, the pivoting coupling allowing the wiper blade to move independently of the wiper arm through rotation of the wiper blade around the pivoting coupling, the wiper blade comprising:
first and second surfaces opposing one another and oriented perpendicular to a base surface of the container;
a void space between the first and second surfaces; and
at least one opening in the first surface and/or second surface through which liquid may flow from the container into the void space.
2. The additive fabrication device of claim 1 , wherein the first surface of the wiper blade is configured to contact the base surface of the container, and the second surface of the wiper blade is configured to maintain a fixed distance above the base surface of the container when the wiper moves across the base surface.
3. The additive fabrication device of claim 2 , wherein the wiper blade further comprises at least one stabilizing feature configured to contact the base surface of the container and located at an opposing side of the wiper blade from the first surface.
4. The additive fabrication device of claim 1 , wherein the pivoting coupling comprises a pin joint including a pin, and wherein the pivoting coupling allows the wiper blade to move independently of the wiper arm through rotation of the wiper blade around the pin.
5. A wiper configured to be used within an additive fabrication device, the wiper comprising:
a support structure configured to be attached to one or more components of the additive fabrication device;
a wiper arm coupled to the support structure, the wiper arm having a long axis aligned in a first direction; and
a wiper blade coupled to said wiper arm via a pivoting coupling, the pivoting coupling allowing the wiper blade to move independently of the wiper arm through rotation of the wiper blade around the pivoting coupling, wherein the wiper blade has a long axis aligned in the first direction and comprises:
a first surface and a second surface aligned perpendicularly to the first direction, the second surface being longer than the first surface; and
a void space located between said first and second surfaces and configured to hold liquid.
6. The wiper of claim 5 , wherein a volume of the void space is between 5 cm 3 and 25 cm 3 .
7. The wiper of claim 5 , wherein the first surface of the wiper blade comprises at least one vent through which liquid held by the void space of the wiper blade may pass.
8. The wiper of claim 5 , wherein said rotation of the wiper blade around the pivoting coupling is a rotation about an axis aligned perpendicular to the first direction.
9. The wiper of claim 5 , wherein the pivoting coupling comprises a pin joint including a pin, and wherein the pivoting coupling allows the wiper blade to move independently of the wiper arm through rotation of the wiper blade around the pin.