Cost-Effective 3D Printing of Silicone Structures Using an Advanced Intra-Layer Curing Approach

We present an advanced, low-cost 3D printing system capable of fabricating intricate silicone structures using commercially available off-the-shelf materials. Our system used a custom-designed, motorised syringe pump with a driving lead screw and excellent control of material extrusion to accommodate the high viscosity of silicone printing ink, which is composed of polydimethylsiloxane (PDMS), diluent, and a photo-initiator (LAP). We modified an open-source desktop 3D printer to mount the syringe pump and programmed it to deposit controlled intricate patterns in a layer-by-layer fashion. To ensure the structural integrity of the printed objects, we introduced an intra-layer curing approach that fused the deposited layers using a custom-built UV curing system. Our experiments demonstrated the successful fabrication of silicone structures at different infill percentages, with excellent resolution and mechanical properties. Our low-cost solution (costing less than USD 1000 and requiring no specialised facilities or equipment) shows great promise for practical applications in areas such as micro-fluidics, prosthesis, and biomedical engineering based on our initial findings of 300 mu m width channels (with excellent scope for smaller channels where desirable) and tunable structural properties. Our work represents a significant advance in low-cost desktop 3D printing capabilities, and we anticipate that it could have a broad impact on the field by providing these capabilities to scholars without the means to purchase expensive fabrication systems.