Two-pinned Lewis
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A Two-pinned Lewis is a stone-lifting device consisting of two 13 mm diameter steel pins, linked by a short chain. The pins are inserted into opposing holes that are drilled into the top of the stone at about 15 degrees from vertical, and at least 75 mm deep.
It operates by gripping the stone (like two fingers lifting a tenpin bowling ball) as the weight of the stone is taken up by a crane or winch. The advantage of using this type of Lewis is that it is simple to prepare - two angled drill holes are all that is necessary.
Like other types of Lewis, it is susceptible to pulling out as the stone is lifted. It should always be tested before hoisting, and used in conjunction with safety slings.
