I was wondering why it seems that there are some skimmers that work well right away and some skimmers take a week or two to break in. It seems like it's not just particular brands or models either. Anyway just looking for your thoughts.
Might have to do with manufacturing processes. Some plastics take a while to "cure" or wear off mold release agents. Do what most on here do. Run it with a vinegar solution for a day or so and it'll be broken in.
Plastics are often covered with a VERY light film of some sort or another of oil, from their manufacturing processes......these oils "wear" off in the first few days of use....this period is the break in.....it can be eliminated by thoroughly cleaning the new skimmer with a strong vinegar solution....or just give it a few days....
The mold release agents are normally silicone, zinc stearate, lecithin, or urethane based.
You need to clean anything plastic that you use thoroughly. The release agents are used to help the part eject from the mold that it was produced in or it will sometimes aid in the actual plow of the plastic throughout the mold. Some plastics have released in the resin itself such as Lexan.