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Ancient sailing ships did not require sheers to erect their masts, as they could be lifted into place by ropes and allowed to pivot around their feet. As ships became larger, their larger and heavier masts were no longer able to be handled in this way. A crane was needed, tall enough to lift the
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In the late 19th century, the increasing size and capacity of general harbour cranes began to overlap with the lofty but lightweight masting sheer and so their specialisation was no longer required.
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towers, with wooden jib structures atop them. Few have survived intact, but some of the towers remain, having now lost their jibs.
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entire mast vertically and then lower it into the ship. By the 18th century, such sheers were a necessity in any large shipyard.
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59:" is an old name for a fixed crane formed by one or two wooden beams, fixed at the base and supported by ropes.
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is a specialised shipyard crane, intended for placing tall masts onto large sailing ships. "
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As sheers are not required to move, they were often constructed as
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143:This article related to shipbuilding is a
66:18th century French masting sheer, with
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147:. You can help Knowledge (XXG) by
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123:. London: Longmans. p. 295.
120:Useful Information for Engineers
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21:Frederik V's Masting Sheers
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68:treadwheel crane
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35:. Built 1746
188:Categories
101:References
94:Sheer hulk
29:Copenhagen
117:(1856).
88:See also
79:masonry
33:Denmark
57:Sheers
49:shears
45:sheers
25:Holmen
145:stub
51:or
23:at
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