Page 1 of 1

About polishing the glass in the kiln

Posted: Wed Mar 13, 2013 4:45 pm
by Havi
Dear friends,
I am trying to sum up all the possibilities I know for polishing glass inside the kiln. However, I miss the details of the temprature when it matures. And of course miss experience -

1. FIRE POLISHING - at what temprature does the glass [Bullseye glass] melt to fire polish? Satin finish, and / or full shine.

2. BORAX POLISHING - to what temprature to I have to go if and when I use Borax as the means for polishing? It is my understanding that Borax can also prevent devit.

3. SPRAY A - again, at what temprature does it melt? I once used spray A for polishing, and it remained white scum on the piece - never became treansparent or shiny. Can this be cured at all?

4. GLASS POWDER - recently I found out that if I sprinkle glass powder [BE 08, NOT frit], it adds shine to the piece, and works like I was capping it. Yet, I do not have to worry that much about bubble squeeze, as I would do, when capping with a sheet glass.
I did a very conservative schedule for this firing, consequently, to my surprise the powder melt at 701 C, yours 1293.8 F

I would be very very grateful for your imput, your experience
and your recomandations


many thanks in advance,


Havi

Re: About polishing the glass in the kiln

Posted: Wed Mar 13, 2013 6:45 pm
by Bert Weiss
In my experience borax and Spray A both require 1400ºF. Others report a little lower. I remain skeptical.

Getting sandblasted glass to gloss is a function of heatwork which is a combination of time,temperature, and mass in the kiln.