Materials:
- PVC pipe 32 mm;
- pipe plugs – 2 pcs.;
- long M6 bolt, 2 washers and nut;
- compression spring;
- sheet plastic;
- rubber or silicone for sealing gaskets;
- pneumatic straight fitting;
- any lubricant.
The process of manufacturing a pneumatic cylinder from PVC pipe
6.5 mm holes are drilled in the center of one of the plugs.
A rubber gasket is glued onto the second from the inside to absorb impacts of the cylinder rod in the future.
A long bolt is inserted into the plug with the hole.
Then a metal washer is put on it, a long spring, a washer again, and everything is tightened with a nut.
Next, put on alternately homemade 3 plastic and 2 rubber or silicone washers.
The diameter of the plastic ones is 26 mm, the rubber ones – 29 mm.First, the plastic washer is screwed on so that a thread is cut on it, then the rubber washer is tightened and the rest are tightened in the same order. It is important not to overtighten the plastic washers so that the rubber has room to press inward. A gap of 1 mm between them is sufficient.
Next, take a piece of pipe several centimeters longer than the spring. In this case, the spring is 14 cm and the tube is 17 cm. A plug with a rubber gasket is glued or soldered onto the tube.
A hole is drilled into the side of the plug and a pneumatic fitting is screwed into it. When tightened, it will cut a thread into the PVC itself.
Then take a plug with a rod and make a small hole in it to vent air.
After this, the rod is inserted into the tube.
Due to the fact that the plastic washers are smaller than its diameter, and the rubber washers are larger, they work together like a piston. Before closing the cylinder, a little lubricant is poured into it. Also, grease is poured through the fitting.
To be able to disassemble the cylinder to replace rubber bands, it is better not to glue the plug with holes. It is enough to drill it from the side along with the tube and tighten a small screw.
Now, when you apply compressed air from a compressor or cylinder to the pneumatic cylinder, it will push the rod out. If you remove the pressure, the spring will return it back. To do this, you will need to adjust its strength. This is done by tightening the nut on the rod.
This is where the removable plug comes in handy. The spring should press enough to force the rod back when the air supply stops, but not so much that the compressor cannot compress it.
