Abstract: In a method of cutting roofing shingles, multiple webs of roofing material are moved to a cutter. The webs are positioned in stacked relationship prior to the cutter. The webs have distinct portions such as tabs. The locations of the distinct portions of the moving webs are sensed by sensors. End cuts are simultaneously cut through the multiple stacked webs with the cutter to produce separate roofing shingles from the webs. The movements of the webs are controlled, based on the sensed locations of the distinct portions, so that the end cuts of the roofing shingles are positioned at predetermined locations relative to the distinct portions.

Abstract: A method and apparatus are provided to place a series of timing marks on a granule covered roofing sheet. A rotary pattern cutter cuts a pattern of tabs and cutouts in the continuous granule covered sheet. The rotary position of the pattern cutter and the position of the timing marks are sensed, and the position of the continuous granule covered sheet with respect to the rotary position of the pattern cutter is synchronized in response to the sensed position of the timing marks and the sensed rotary position of the pattern cutter.

Abstract: A method and apparatus are provided to place a series of timing marks on a granule covered roofing sheet. A rotary pattern cutter cuts a pattern of tabs and cutouts in the continuous granule covered sheet. The rotary position of the pattern cutter and the position of the timing marks are sensed, and the position of the continuous granule covered sheet with respect to the rotary position of the pattern cutter is synchronized in response to the sensed position of the timing marks and the sensed rotary position of the pattern cutter.

Abstract: In a method of cutting roofing shingles, multiple webs of roofing material are moved to a cutter. The webs are positioned in stacked relationship prior to the cutter. The webs have distinct portions such as tabs. The locations of the distinct portions of the moving webs are sensed by sensors. End cuts are simultaneously cut through the multiple stacked webs with the cutter to produce separate roofing shingles from the webs. The movements of the webs are controlled, based on the sensed locations of the distinct portions, so that the end cuts of the roofing shingles are positioned at predetermined locations relative to the distinct portions.

Abstract: In a method of cutting roofing shingles, multiple webs of roofing material are moved to a cutter. The webs are positioned in stacked relationship prior to the cutter. The webs have distinct portions such as tabs. The locations of the distinct portions of the moving webs are sensed by sensors. End cuts are simultaneously cut through the multiple stacked webs with the cutter to produce separate roofing shingles from the webs. The movements of the webs are controlled, based on the sensed locations of the distinct portions, so that the end cuts of the roofing shingles are positioned at predetermined locations relative to the distinct portions.