Laser Cut Millifluidics Chip

These instructions will allow to create a millimeter-scale fluidic chip that can withstand relatively high flow rates (and pressures) without leaking.

• Use the provided files to laser cut your two acrylic pieces and one rubber piece, as seen in the table
  • If available use pressurized air to clear any debris from the laser cut rubber, specifically inside the channel

• To create pressure distributing sheet metal strips you will need to cut 2 pieces of sheet metal
  • The strips should be approximately 1 cm by 7.5 cm
• Align the cut sheet metal with the laser cut acrylic pieces and use a marker to draw a dot where each acrylic hole lines up as pictured
  • These are where the screws will go
• Use hand punch to punch through the marked holes
  • If the metal strip is obstructing the step part of the geometry, punch out a half circle to create window for the step

Make sure you have all pieces pictured before assembly.

• Layer the sheets in the following order going from the bottom and working up: acrylic sheet with exit/entrance holes (part E), rubber sheet (part C), acrylic sheet base (part D), and the metal sheets on either side of the channel (part A and part B)
  • Ensure that all of the holes line up through all four layers
• Place the screws in each hole, they should be placed going in the opposite direction of the assembly, then place the nuts on the screws (screw head should be on part E, the nuts should be on parts A and B)
• Tighten the nuts slowly and carefully to minimize deformation
  • Do not fully tighten one screw then move on to the next, tighten each screw little by little and work diagonally from your previous nut, similar to the way a tire is tightened
• Pictured is a cross section of the assembled chip. From top to bottom the layering goes part E, part C, part D, and parts A and B

• For preliminary testing to ensure the nuts are tight enough, attach the tubing to the syringe and fill the manual syringe with dyed water
• Connect the manual syringe to the chip’s inlet and fill the chip with water
• If you do not see any leaks at this step you are ready for more testing

• Use epoxy to adhere the needle head to the entrance and exit of the device
• Connect the tubing at the entrance and exit of the device
• Attach the tubing to your syringe pump and turn it on
• Now you can observe your flows through the device!