At 08:53 -0400 17/10/08, Serge Harel wrote: >The better the felt the more sensitive the are thatÊwhy Ray andÊme >has good result withÊourÊold fashion way to make hammer. >The hydraulic could not make tension hammer like l do on the picture. Serge, pressure is pressure, and the only difference I can tell between pressure applied by screws and pressure applied by hydraulic or pneumatic rams is that with these the pressure can be accurately measured and differentially applied. As Dolge says, speaking of machines younger than yours: "...with the present machines, the operator has no control over the pressure exercised; he does not know but has to guess whether the felt is pressed down sufficiently or not. The rigidness of the covering machine does not permit of any variation in pressure to be used, so necessary on account of the uneven texture of the felt..." There you have it from the horse's mouth. JD
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