Modular build platforms for additive manufacturing

A system for manufacturing dental appliances, the system comprising:

• a modular build substrate comprising:
• a carrier, and
• a plurality of build platforms releasably coupled to the carrier;
• a printer assembly configured to receive the modular build substrate, wherein the printer assembly comprises:
• a source of a curable material, and
• an energy source configured to output energy toward the curable material to form a plurality of dental appliances on the plurality of build platforms of the modular build substrate according to a lithography-based additive manufacturing process, wherein each build platform of the modular build substrate receives at least one dental appliance;
• and
• at least one post-processing device configured to perform at least one post-processing operation on the plurality of dental appliances while the dental appliances remain on the respective build platforms and while the respective build platforms are separated from the carrier, wherein the at least one post-processing device comprises a centrifuge configured for centrifugation of the dental appliances on the respective build platforms, and wherein the plurality of build platforms have a stiffness configured to resist bending during the centrifugation.