Introduction: 2 Way Dust Extractor Valve
Start with a 40mm plastic tee and 3 short pieces of tubing say 30 cm long.
Step 1: Step 1
Start with a 40mm plastic tee and 3 short pieces of tubing say 30 cm long.
Step 2: Step 2
Carefully measure the inside diameter of the 40mm pipe.
Step 3: Step 3
Get 2 large choc block electrical connectors and strip off the plastic with a craft knife. The one I used had a 4mm hole through it.
Step 4: Step 4
Cut a disk from 6mm plywood so that it is just a little smaller than the internal diameter of your tube. In the centre of the disk cut a rectangle the same size as the choc block connector so it fits in with the screws pointing out. I used a laser cutter here if you have one. If not you could 3d print or drill and file out.
Step 5: Step 5
Drill a 4mm hole down through the disk making sure it is exactly on centre as shown.
Step 6: Step 6
Areldite the choc block connector into the hole using a 4mm steel tent peg to centre it.
Step 7: Step 7
Bend two 4mm steel tent pegs so that they form the shape shown with the straight portions approximately 50 mm long.
Step 8: Step 8
Drill 4mm holes vertically through the two side pipes approx 25 to 30mm from the tee piece making sure the holes are exactly vertical.
Step 9: Step 9
File flats on the two bent tent pegs so that they engage with the choc block screws at 90 degrees to each other and assemble the valves one open and one closed. You may have to round the edges of the disks to ensure that they turn smoothly within the tube.
Step 10: More Pics
Step 11: More
Step 12: Step 10
Add a wooden bar across the top so that the valves open and close together and fasten with nuts onto threads cut in the tent pegs.
Step 13: Step 11
Add an end stop to the tube made from a ring of ply or acrylic and 3/4 rings to form backstops. These make sure the positions are accurately located. A spring also keeps it in position or you can embed 2 pairs of magnets, I used some from those popular ball magnet clusters that were fashionable some time ago and these give good position location.
