http://www.boingboing.net/2008/04/28/artist-repairs-spide.html
All of the patches were made by inserting segments one at a time directly into the web. Sometimes the thread was starched, which made it stiffer and easier to work with. The short threads were held in place by the stickiness of the spider web itself; longer threads were reinforced by dipping the tips into white glue. I fixed the holes in the web until it was fully repaired, or until it could no longer bear the weight of the thread. In the process, I often caused further damage when the tweezers got tangled in the web or when my hands brushed up against it by accident.