How best to make glue/resin I wanted to model the inside of this lightbulb screw, specifically the red glue (or resin) and uneven edges/mottled look it has... any ideas on how to do that? I've modeled a rough shape for the area where it dips from the rim but not sure whats the best way to get an 'organic' look...

Any help?
I approached this by creating a custom texture. First I Marked three seams in the base mesh CTRL + E > Mark Seam. 



Then unwrapped it. By selecting all of the vertices and pressing U > Unwrap. I scaled the UV Map larger because I was only interested in the area I applied the custom resin texture to.



Then exported the UV layout and in an image editor created a custom texture. Of course turned off the UV Layout before saving the finished texture.