Cast Iron Help Please

I have had this for many years, got it used. I believe I treat it correctly, no soap, use oil. For a while now it has developed this rough area going around the edge. I have attached 2 pics. One of them has a blue arrow pointing to the area I am talking about. Does anyone know what is causing this ? How do I get rid of it ? What ever it is it does flake off on its own but I can not easily get it off and is hard as nails. Just before taking this pic I washed it with hot water and rubbed it with salt. Thank you for any help.

 

Looks like excess oil that enameled on the outside. Nothing really to worry about but it’s a sign that you’re over-oiling the pan before running it through heat cycles. You should only be using a small amount of oil with a high smoke point to coat the pan. It’ll continue to build up but it’s not easy to take off unless you get aggressive with it- nothing to worry about though.

 

That's oil that has turned into a polymer under extreme heat.

You can get rid of it with wet/dry sandpaper, barkeepers friend or even coarse sea salt flakes and some elbow grease.

It won't be detrimental to your seasoning layer either. Just go ultra thin on the oil next time you go to season/burn it

 

Here’s the main cast iron thread if you want to dive down the rabbit hole:

https://www.tacomaworld.com/threads...on-or-dutch-ovens-go-here-post-them-up.97176/

 

@GHOST SHIP thank you, I will use less oil from now on, im going to go take a look at that thread, thank you.
@Clinch Mountain Preacher Thank you, I think I am going to try the wet sand paper method, maybe put it on my random orbital,,,easier then elbow grease Thank you.

 

If you're not sure if you have too much oil when seasoning it, you have too much oil.

 

I just finished resurfacing one of my carbon steel pans. In the past I tried doing slow on the oven.this time I said, f it and went full retard on a gas burner outside. I also sanded it to 800grit. This is supposed to be a good roughness for polymers to adhere to. I followed it up with some deeper scratches that I'm hoping with further help.

For each coating, I poured a put a teaspoon and quickly wiped it with a paper towel.

Not sure if the scratches will help or hinder or if I'll even notice.

 

Well everyone thank you for all the help. I ended up using this Disc kit in my drill to clean the pan. Taking my time it took about 30 minutes to accomplish. Thank you all for the time and help.

 

Looks great! Post a followup after it's seasoned.

 

@soggyBottom Thank you for asking, here is a pic after first seasoning. I think it would be good to do another seasoning before using it. Thank you all for helping.