Last week I had a request for a piece of widow fabrication equipment called a Rig. It's used to square up doors and windows during the final stages of manufacture. A Rig typically has a leaning side for windows and a vertical side for doors, and uses sliding poles which lock into the window and door extrusions. Being an open structure allows staff to work on the windows and doors from either side.
This customer had an issue with their current setup. Their version of a Rig was attached to the building, and they are based in a geographic area which suffers from earthquakes. I live in Christchurch and can proudly say that I know more about earthquakes than most as our city feels around a thousand quakes a year including some devastating whoppas back in 2010 and 2011. The issue the client has is that their earthquakes move their building and put their Rig out of square. You can imagine the implications of using a non-square Rig to square up window and door frames. Not good.
The answer is to make a new Rig (or modify the existing) to be freestanding, with an option to mount the Rig on rubber feet. By not being tied to the building the effect of quakes should be reduced.
Our Rigs are constructed so that levellers can be fitted underneath the mounting points to ensure the Rig is square when installed, and also so that it can be re-squared if the floor level changes, as is very common in my home town.
All that said, a Rig is a brilliant item for most window fabricators as it reduces the time to glaze and finish doors and windows, and reduced potential issues at site installation resulting from non-square items.