I posted something on this a while back, but I keep seeing people post concerns about damaging natural gut crosses during weaving and tensioning. Lots of stringers use some kind of lube, with wax being a favorite for old schoolers. If you take a shoeshine sponge (not one with color - just something to impart a shine) and rub your mains after installing them (top and bottom), the silicone in the product will lube your gut crosses and reduce or eliminate damage from friction as you pull the natural gut to tension and straighten them out. This takes all of 5 seconds and puts a tiny amount of silicone on the strings. I have not found this to harm either the mains or crosses since I started doing this. When you take out a set of synthetic gut strings and they are slick with a clear liquid, that is silicone lube. When these are the mains, you don't need to add any more lube.