These springs, made from old car tires, are what makes this screener unique. Steel coil springs are seen most often on other screeners. Trouble with coil springs is finding an effective way to mount them. The tire springs are easy to mount and are also free! One tire took care of all rubber needs for the screener.



I tried using springs made from radial sections of the tire (same as the hinges in Step 3) but that shape was a bit too flexible. The springs shown were cut from the center circumference of the tire. Each spring is about 16 inches long before being formed into the required U shape.



The jig shown in the photo is pretty well essential to hold the spring in position for drilling.



I clamped the pressure treated 2x4 leg, along with the tire spring, in the jig and drilled the holes completely through the whole works with an extra long 3/8 inch twist drill bit.



After I removed the spring from the jig I ran a 1/2 inch drill bit through the 3/8 inch holes to make it easier to insert the 3/8 inch bolts.



Once mounted on the hinges and springs the screen frame and chassis have no metal to metal contact. The V belt makes another "rubber" connection to the engine. This all helps make a smooth running and quiet screening machine.



The jig labelling (photo above) shows where a hole is drilled for a "spring tension bolt". The idea was to install a bolt with washers and a nut to adjust the bulge of the spring if the screener frame, and belt tension, loaded the spring down too much. After many tons of screening the spring has maintained its shape so the spring tension bolt has not been tried.