Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: removing glaze from porcelain
Organikum
resurrected
*****




Posts: 2339
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: frustrated

sad.gif posted on 8-2-2004 at 04:40
removing glaze from porcelain


I have some nice thin porcelain cups which call for being abused as cell dividers in a electrolytic setup but........

...they are glazed and so useless.

How to remove the fucking glaze without a sandblaster? Dont say "gringing stone" or "abrasive wheel" I already destroyed two cups by trying this. As soon the wheel brakes through the glaze it breaks the cup as the porcelain below is to thin and much softer than the glaze.
I also would like to leave some glaze at the rim for preventing electrolyte getting sucked up there.
Molten NaOH seems to have no effects at all on the glaze - perhaps it is just a question of time?




Irgendwas is ja immer
View user's profile View All Posts By User
Hermes_Trismegistus
National Hazard
****




Posts: 602
Registered: 27-11-2003
Location: Greece, Ancient
Member Is Offline

Mood: conformation:ga

[*] posted on 8-2-2004 at 08:40
Glass etching paste/sandblaster in a can ?


These products are pretty common here sold by Armor Etcha and Etchall

I'm sure they'd send them internationally but maybe there are similar companies in your neck of the woods.
http://www.etchworld.com/cgi-bin/cp-app.cgi
http://etchall.com/

if you wanted to do it manually and have alot of time on your hands try replacing your grinding wheel with a felt wheel and abrasive pastes/fine pumice (rock shops)




Arguing on the internet is like running in the special olympics; even if you win: you\'re still retarded.
View user's profile View All Posts By User
Friedrich Wöhler
Harmless
*




Posts: 42
Registered: 7-2-2004
Location: Germany
Member Is Offline

Mood: No Mood

[*] posted on 8-2-2004 at 09:32


Hallo, k. und k. Hof-Chemiker Organikum, :)

I wonder absolutely that molten NaOH (!) or boiling in conc. NaOH-solution shouldn't take effect...
Then try an H2F2-based problem-solution. There are (expensive) hobby sets available for glas corroding.
2th solution could be H2F2 or NH4HF2 from a lab-store.
In the EU is a product available what a solution of zinkhexafluorosilikate in water is. This I use as base for fluorine chemicals.I cannot remember its name now. Here is a supplier with another name of this product:
http://www.bornit.de/pages/produkte/merkbl/pdf_dateien/sdb/a... (pdf-file in German language).
Or search in google for German trading-synonyme "fluat" or "mehrfach-fluat".

Greetings to Mozart's country!




Kein Schwanz ist so hart wie das Leben.
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2339
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: frustrated

[*] posted on 8-2-2004 at 20:04
Tried it again...


with molten NaOH and - oha! - this attacks the glaze after some time!
And produces such wurface tensions that the cups burst apart and then broken, they dissolve slowly. The unglazed inside first is understood. :mad:

Ok.
Now I retry the boiling hot NaOH saturated solution overnight and will probably go to hunt down some etching fluoride here tomorrow - probably I will buy an sandblaster after I have seen the price.... LOL.....

No, probably I will go to a pottery and have the stuff made what will be much cheaper and better as fucking around with this by myself.
Hmmm. some electrolysis diaphragms and a set of retorts and tubes for the high-temperature and chlorine stuff.

Sounds good.
oh yes
:D




Irgendwas is ja immer
View user's profile View All Posts By User
axehandle
Free Radical
*****




Posts: 1065
Registered: 30-12-2003
Location: Sweden
Member Is Offline

Mood: horny

[*] posted on 12-2-2004 at 08:27


Why didn't you just buy new ones? They cost next to nothing?



My PGP key, Fingerprint 5D96 E09E 365D 1867 2DF5 C2FE 4269 9C19 E079 CD35

\"Verbing nouns weirds the language!\"
View user's profile View All Posts By User
Turel
Hazard to Others
***




Posts: 141
Registered: 29-11-2003
Location: The Hardware/Software Interface
Member Is Offline

Mood: Thixotropic

[*] posted on 12-2-2004 at 09:30
Glaze Remover


http://www.google.com/search?hl=en&lr=&ie=UTF-8&...
View user's profile View All Posts By User This user has MSN Messenger
Organikum
resurrected
*****




Posts: 2339
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: frustrated

[*] posted on 12-2-2004 at 09:46


axehandle, make your choice:
- because I like to experiment
- because I am stupid
- because I am stupid AND like to experiment.

as you like it.

turel:
This is NOT the glaze I want to remove which Google shows up.




Irgendwas is ja immer
View user's profile View All Posts By User
axehandle
Free Radical
*****




Posts: 1065
Registered: 30-12-2003
Location: Sweden
Member Is Offline

Mood: horny

[*] posted on 14-2-2004 at 01:22


I believe it's because you like to experiment.

You have already proved to me that you're absolutely NOT stupid.

Unless the glaze is made of porcelain enamel, I would suggest sand blasting OR placing the pieces in a kiln at a high temperature, where the glaze hopefully would settle at the bottom.

Otherwise there's always the obvious way: chip of the glaze (carefully!) with the risk of destroying the ceramic substrate.




My PGP key, Fingerprint 5D96 E09E 365D 1867 2DF5 C2FE 4269 9C19 E079 CD35

\"Verbing nouns weirds the language!\"
View user's profile View All Posts By User
thefips
Harmless
*




Posts: 33
Registered: 6-3-2004
Location: Germany
Member Is Offline

Mood: self destructive ;)

biggrin.gif posted on 6-3-2004 at 15:28


Just take HF and your problems should be solved...
View user's profile View All Posts By User
Mumbles
Hazard to Others
***




Posts: 436
Registered: 12-3-2003
Location: US
Member Is Offline

Mood: Procrastinating

[*] posted on 6-3-2004 at 17:10


I think the point was to remove the glaze without damaging the ceramic substrate. I think HF would damage the clay.
View user's profile Visit user's homepage View All Posts By User This user has MSN Messenger

  Go To Top