Burnishing cast iron

[Forty Rod]

Trolling the web and came across an old cookbook site.  (Thought I saved it to my Favorites but can't get it to come up now, so I can't even tell you where it was.) It had a section on cookware preparation and said before you season any new cookware you need to burnish it inside and out to help "seal the iron."

What's that?

I thought burnishing was simply polishing it.

[Delmonico]

Thats what it is and I think the old stuff that came that way seals the pores and don't season as well.  I have old pieces that are polished/burnished and I don't like the way they season as well as the new natural finish stuff.

In metal working burnish is a little less than a true polish.

[Forty Rod]

Thenkyew

[El Peludo]

It'd probably be one he-- of a job, if my interpretation of "burnishing" is correct - burnishing is polishing, but rather than removing a small amount of metal, and making smaller and smaller scratches in the surface, it is done by using a harder metal to rub the surface smooth, kind of like making a smooth finish on concrete - you dont remove any material, just rearrange the surface of it to get it slicker.  Any of you "engineers" out there want to weigh in on this?  There are surely tools for the process; I have several small tools that are made for burnishing contacts in electrical devices, and they are just a thin flexible piece of steel with a matte finish on the surface.  I think that a small clean steel disc without any sort of coating on it, used in a Dremel Tool would do the job on cast iron cookware pretty well.  Probably, an old steel spoon, rubbed vigorously for a while - quite a while - all over the surface, would work, too.  

[Delmonico]

Yeah, I think that is a more correct term and description, either way, burnishing or polishing to me seems to fill the poors and it don't season quite as well, but also modern "Cast Iron" isn't just the old time 4-5% carbon pig iron of old, it has some other alloys in it at least in some cases.  Lodge uses I believe 25% scrap from a machine shop.

What ever it is, they cast better and thinner that the true 150 year old stuff.

[oscar]

n my business we burnish stainless steel. I agree with Del. I have a very old flat griddle at is wonderful and a 30+ plus years old 12" dutch. The newer dutch is much different than the griddle. i don't know why you would want to burnish a dutchoven. When you burnish metal you are rearranging the surface. Microscopically there is a sharp spike like surface on the  metal. The burnishing bends over the points and in effect smoothes the surface. i think the curing/seasoning  process in dutch oven cooking fills in all the areas between the metal spikes, this i'm sure is part of the no stick benifit of the seasoned surface we  all love and revear.

Oscar,