Uh oh. Enamel/porcelain popping off during heating/seasoning

[Spurgeon Hendrick]

Hello guys and gals,
After I took this pot out of the e-tank, washed and dried it ... I started heating it in the oven. When the pot got to 450, I heard a couple of pops. Worried that I had cracked it, I took it out of the oven. The pops I heard were from the enamel (or is it porcelain?) popping off. See pictures below.

BTW - I had decided to leave the band of enamel around the top of the inside. I figured it would look kinda cool. I'm guessing that band remained because it was not in a line-of-sight to the sacrificial metal?

So, my question are:
1. Did I do something wrong as far as how you heat/season coating iron?
2. Should an enameled piece be seasoned at lower temps?
3. Did the electrolysis weaken the enamel?
4. Should I say, heck with the enamel, and put it back in the e-tank to remove the rest?

ID help question:
Now that the bottom is clean(er), I see it has a diamond around the raised H. Is anybody familiar with that logo? Anybody know who made this?

[Cheryl Watson]

Electrolysis does not necessarily 'remove' enamel... UNLESS it is seriously compromised.  That is what you were seeing in the electro... bits of enamel/porcelain floating that had been compromised to the point that oxidation was underneath it.  What porcelain has not come off already, is going to stay put IMO.

The popping off in the oven, once again, would indicate compromised porcelain that water was able to get under.   

The only way to really removed enamel/porcelain is with a pick and hammer,,,, a laborious, time consuming task.

No idea who made it...

 :)

[Tom Neitzel]

Cheryl beat me to the comments.  I agree, electrolysis shouldn't hurt good enamel (procelain).  This old stuff is really fused glass.

Now I did ruin some modern enamel, a John Wright Steamer circa late 70s, by soaking it in vinegar.  It softened up patches, made pits and took away the shine.  Clearly not the same kind of enamel that was used in the old days. :(

Never again.

[Russell Ware]

So, my question are:
1. Did I do something wrong as far as how you heat/season coating iron?
2. Should an enameled piece be seasoned at lower temps?
3. Did the electrolysis weaken the enamel?
4. Should I say, heck with the enamel, and put it back in the e-tank to remove the rest?

1. The answer is yes!

2. FYI, even new enamel coatings are generally labeled to be used at temperatures under 450F. Older enamel, especially that which is not complete, should be left alone. Unless you can get ALL the seasoning oil off, you will typically end up with a blotchy or uneven color added to the enamel from the oil. If you really feel motivated to season, don't go above 350F using any type of treatment. Better yet, just put some mineral oil on it and call it a day.

3. Time and atmosphere weakened the iron and the enamel. Electro did what it should do, it cleaned it right up.

4. There is no guarantee that further electro time will remove the rest of the enamel. The problem arose when the enamel started to crack. The iron starts to rust and the rust eventually gets under the enamel. But in areas you have no cracks, the enamel should still be firmly attached to the iron.

[Spurgeon Hendrick]

If you really feel motivated to season, don't go above 350F using any type of treatment. Better yet, just put some mineral oil on it and call it a day.
.

So, now I have another question ... Can I season the outside and leave the inside without any oil ... and then coat the inside with a little mineral oil after the pot cools down from seasoning the outside? In other words, is it okay to leave the inside "naked" while the pot is in the oven at 350 to season the outside?

[Russell Ware]

Yes you can season only the outside. Before putting mineral oil on the inside, check for any flash rust that may have formed, work it off and then apply mineral oil. Is it for display this way?

[Spurgeon Hendrick]

I reckon. It's the Lodge maslin pan (scalloped bottom) that I found. It must have 50 years of hardened jam on the inside. Still trying to get it clean. Might not be enough enamel left to even worry about. For awhile there I had my hopes up, but they are slowly fading.

[Cheryl Watson]

If it is display only piece... I would apply mineral oil to the entire piece.

Vegetable Oil based seasoning will eventually turn rancid after several years.
(without 'use').

When using Mineral Oil, do NOT heat above 225°, as mineral oil has a very low smoke point, and the fumes/vapors are noxious/harmful, if breathed in.
( I have two persons living here with Asthma, and we all have allergies!) and the fumes are considered to folks without Respiratory ailments....

All of my display only pieces receive the Mineral Oil only treatment immediately after final wash down and drying.

I have large aluminum roaster pans (from a Restaurant Auction) that act as the vessel for the CI and mineral oil.  You do NOT want Mineral Oil dripping into your oven. 

:)