Porcelain Chip Rust Risk ?????

Changed out a cast iron bathtub recently. Looked at it the other day, as it was being prepped for tile. On the corner, fortunately where it will be covered by bitchithene, and then cement and tile, there is a quarter size chip (don't believe metal showing). I put a coat of porcelain repair epoxy on it and no sooner had I did that then the workers put bitchithene on it. I think a worker droped a hammer or staple gun on it from working on the lath on the walls or maybe when it was brought in, it was banged against something. In any case, is it a rust problem waiting to happen? When rust does start in a chip on a cast iron sink, tub, etc. does it eat like cancer through the whole thing or just the surface of the area it is on? Is it worth pulling the bitchithene off, sealing it properly and then putting tile on or should I leave it alone.
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If you didnt go to metal it should be ok
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On Sun, 26 Oct 2003 06:57:21 GMT, someone wrote:
IMHO, don't worry about it.
Cast iron pipe lasts what, 100 years, and it is not enamelled.
This area is not visible and it has been sealed.
I wouldn't worry.
-v.
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