Yours aye, Dusty.The idea came from a need, in a local school, to replace missing or vandalised toilet door locks. I fitted some in 2006, unbeknown to the school authorities. When I visited recently for a swim, there they were – virtually intact.
Door bolts and hooks lend themselves to abuse. The “Lulok” was designed to be anti-vandal – impossible to close the door in a “locked” position and fairly resilient to impatient “waiters”.The “Lulok” consists basically of a steel chain link (one) welded to a short piece of round bar, attached to the closing side of the door by a bolt, plus a staple/plate or a suitable hole, depending on the door frame design.The “Lulok” we made used ¼” (6mm) chain link with a 10mm diam bar piece. The link needs to be uniform in section – or ground flat – and welded on 3 sides of the joint with the bar, so that the bolt can slide unhindered along the inside length of the link. We counter-bored the outside of the door surface to hide the nut (sealed with “nutlock” or a “nyloc” nut) under painted epoxy or the old occupation indicator plate. The bolt-head needs to bridge the link slot (we used slotted head 6mm screw bolts). A washer may be needed between the link and door surface (we omitted one), but he bolt must not be pulled tight, but remain slack enough to allow smooth sliding of the link and for the “Lulok” to drop to the vertical “unlocked” position under gravity after use.
"The Earth is the Lord's and the fulness thereof"
June 2019
Again I happened to visit the school, and the locks were still in operation! Thirteen years after installation. A good testimony. Dusty.
June 2019
