Need advice for an etched tub

[Donski]

Hi,
I was cleaning the grout in my tub surround and after letting it sit for a while, I found that the cleaner had dripped down onto the tub and etched the porcelain over cast iron tub. Is there anyway to polish the etched places? I thought someone may have made this mistake before.

Thanks
Don

 

[Jadnashua]

Buffing the surface out to the original luster is sort of an art. It can be done, but it somewhat depends on how deep the etching went. To get the surface smooth, you have to sand down the high spots until it is all flat, then progressively polish it with finer and finer grits until you achieve the desired polish. Do it wrong, and you can make things worse and the worst case would be you go through the original finish and expose the cast iron beneath!

You'd need progressively finer grits maybe up to 5000 or so, and a fine polishing, buffing wheel a the end. Depending on the rest of the tub, you'd have to know when to stop, otherwise, you'd end up with that spot highly polished, and the rest now looking dull. Trying to polish the whole thing is likely beyond what you could do in a home, and would be very time-consuming and highly skilled operation.

 

[Sponsor]

 

[Jeff H Young]

never tried or seen cast iron enamel buffed they might use a compound? Im thinking its a specialty but perhaps granit or stone finisher can do it?

 

[Jadnashua]

The enamel finish is essentially glass, and yes, it can be polished, but it's a bit tough to do. It's harder than paint, but softer than most stone. The key to polish anything is don't skip grits. Each grit erases the scratches of the rougher one. Skipping grits just takes lots longer and isn't as efficient. The final polish is often best done with a buffing wheel and a polishing compound, but the surface must be flat before you start or it will look funky. Etching creates a rough surface, so you have to smooth it first, then gradually remove the scratches you make while sanding it before you polish things off at the end.

 

[Jeff H Young]

most cast iron isnt flat its bumpy shows a texture to it , at least the newer stuff perhaps the dull older finish dosent show the .
anyway hope it turns out and Donski posts how he did it and his results

 

[Jadnashua]

If the etching is on a textured surface, it will be much harder to get a good outcome. You can't sand it, and if you try buffing it, you're more likely to wear down the high points than get into the lower ones too into the texture.

Trying to get a good representation in a picture might be tough, but you could try, then we'd see what your issue is.

 

[Donski]

Hi,
I was cleaning the grout in my tub surround and after letting it sit for a while, I found that the cleaner had dripped down onto the tub and etched the porcelain over cast iron tub. Is there anyway to polish the etched places? I thought someone may have made this mistake before.

Thanks
Don

Thanks for all of the replies. The etching isn't deep. It's just lost it's luster. I'll give it a try in an inconspicuous spot.

 

[Jadnashua]

If the etching is not deep, you can probably start with a fairly fine grit. You might just try with a buffer and polishing compound. If that doesn't make any progress, you'll need a rougher grit and work your way up to the finest you want to achieve the shine you desire.