FACT FILES

Clappers & Crown Staples
 

Accurate calculations
When designing a new set of clappers and crown staples we take great care to ensure that the clapper throws and other dimensions are correctly graded. Clapper and crown staple dimensions are calculated using complex and carefully guarded formulae. By this means all the clappers in a Nicholson installation will work well together as a set and this is particularly important where a ring includes bells of differing profile. Our installations are widely acclaimed for the way in which the bells seem to "flow" well and the correct calculation of the dimensions for the clappers and crown staples is one of the most important ingredients in achieving this.
New clappers are normally of ductile iron although we also have full blacksmiths facilities and thus are able to produce wrought clappers to special order. Clappers are fitted with bushes turned from solid Tufnol which are then resiliently mounted in the clapper eyes using neoprene rubber. Clappers are hung from independent crown staples which are fitted with stainless steel hinge pins, thus ensuring the lowest maintenance requirement allied to the longest possible life expectancy. Crown staples are always fitted with oak-bark-tanned leather insulation washers for fitting between the crown staple and the inside of the crown of the bell.