What are mechanical wall ties?
Mechanical ties are stainless steel threaded studs that are fitted with an expanding mechanism at each end. The expansion mechanisms are usually in the form of a neoprene sleeve held between nuts and washers. The ties are available in a number of sizes to suit the most common cavity widths.
How do mechanical expanding ties work?
A clearance hole is drilled into the hosting masonry and the tie is inserted. When torque is applied to a part threaded torque-nut it turns the bar forcing the nuts and washers at the far end of the stud closer together and squashing the neoprene tube. As the tube is squashed it expands radially to tightly grip the wall of the hole in the inner-leaf masonry. At a factory set torque level, the part-threaded torque nut works its way down the bar to radially expand the neoprene sleeve at the near end of the stud to engage and grip the outer wall. The ties have a small neoprene drip-ring placed in the central portion of the bar to guard against the passage of water.