Piston Recorder (NU-237)

These high quality Piston Recorders are precisely manufactured. The glass cylinders are made of specially drawn and annealed glass tubing, which has been ground true. The aluminum alloy pistons are individually matched to the cylinders. The Recorders are extremely flexible and adjustable. The glass cylinder is mounted in a metal base and has a riffled tubing connector at the bottom. The cylinder is held in a split bushing operated by a large knurled knob and can be vertically adjusted. The aluminum alloy piston has a rocker arm that can be connected to any of 9 holes in the writing lever arm. The holes are spaced on a 4 mm pitch from the fulcrum. The writing lever arm has an adjustable counterpoise weight. The entire cylinder and piston assembly can be moved in and out of the hollow stem for horizontal adjustment and locked securely in place when adjusted. In this manner, the amplitude of the writing lever can be adjusted. The writing lever terminates in a connector for a writing point. A pressure transducer can be used in place of the pen. The stem is 9.5 mm (3/8 in) in diameter.