Continue on Texture molds and 4 and 5/8th slumping mold.

 

This morning I am full fusing a few trinkets using the following schedule:

400dph............................1225.................20 mins
600dph.............................1470................10 mins
Full .................................900....................1 hour
150..................................700.....................0
Off


Just a few items while I decide how to proceed.  These are beads or potential pins.  I have a pin back in my pocketbook.  Meanwhile I am going to cut glass for tomorrows project using the texture mold.  What is the best glass to use with a texture mold?  should it be opaque or transparent.  I have already used an opaque and that turned out ok although I was not crazy about it, so this time I will use transparent with a clear base.  Also the next time I can use transparent with a black base.  I will cut this to 4 and 5/8ths square so that I can slump it on my mold.  And I should continue preparing for my tiles.  Tiles will be four inches square.

Thisis one of my new texture molds and I am going to reproduce that with a transparent green glass with clear base.  I am going to do this with 5 mm of glass rather than 6mm which is what I used in the first try that came out quite well and the people in the store want that one, so this time I will hold it a little longer at the first and segments of the firing schedule and lower the firing processing temperature as follows:

300dph..............................................1360 degrees...................... hold 20 min
500dph...............................................1460 degrees......................hold 10 mins
Full.......................................................900 degrees......................hold 1 hour
100 dph.................................................700 degrees.....................hold 1 min

This pretty textured mold is called the Cherry Blossom Texture mold.  I will fire this at the above schedule.
Well I cannot get the picture to work but basically what happened was the sides pulled in as if it was too hot and not enuf glass so I will go back to initial texture mold and use two 3mm pieces of glass, same firing schedule and hope for the best.

Now it is working.  This is what came out pulling swollen side.  Lets try to make it better.
So I did another with other texture mold but this time I used two pieces of 3mm glass, blue transparent and white opaque and I used the firing schedule on Delphis instructions.  It came out pretty well but their appears to be a little white stuff on one corner  I am soaking it now in white vinegar and will try scrapping it off after a day of soaking, but it could be dvitrification.  In that case I will do another piece but ramp up quicker in segment two like I did originally and try that.  I will also use transparent glass with clear transparent instead of opaque.  Two different colors do not look so good so perhaps I should two of the dame color instead.   I will have to clean the mold and respray it.  Lets hope it works better.

I have learned so much this time around.  I tried the first texture mold with the 4 segments with 2 pieces of 3mm glass and it came out with rounded sides but what appeared to be devitrification on the top.  Not completely sure it was devit but I tried to soak it in vinegar and then scratch it off.  That did not remove off, so I tried covering it with a layer of white powder and firing it to 1425 degrees with a 10 min hold.  Thought that it might remove the design of the texture mold which I had in the glass and it did.  So what causes devit, a couple of things...going to slowly while ramping up to the processing temperature and also residue.  In this case I think I had both, not sure which one caused it so in the next firing I will try to correct for both.  And now I also see the using the Boron Nitrate spray on these molds, while easier, does not work as well.  So I purchased some more molds and when I get them I will cover them with Bullseye glass separator.  In this last firing I put my glass directly on the shelf, however there was a part, a small part of the shelf, that was not covered with glass separator and when I pulled up my piece of glass a piece of the shelf, albeit very small piece, came with it.  Idiot, I should of known this.  So now before I do any piece that I want to put directly on the shelf I have to scrape off the old glass separator and apply new.  I am planning to use molds for the next few firings so they are elevated off the shelf and the glass is put on them. 

My next firing will be on the 4 segment texture mold that I have sprayed with Boron Nitrate.  Once having covered a mold with Boron Nitrate spray one cannot start covering the mold with a different glass separator.  I looked at the mold and noticed what looks like patches that are heavier or thicker than other patches, perhaps there is some extra residue there.  Before putting glass on it I am going to try wiping it with a dry cloth and vacuuming the inside of the kiln to make sure there is no remaining residue, hopefully.   And for the firing schedule, I will use the following:

300 dph..............................................1360 degrees..........................hold 10 min
500 dph..............................................1465 degrees..........................hold 10 min
Full......................................................900 degrees...........................hold 60 min
100 dph................................................700 degrees.......................... hold 1 min

 

Experiment 1:  I have brushed off the old Boron Nitride spray and re-sprayed the mold.  On top I placed a small rectangle of clear glass covered with the same size rectangle of a darker clear glass, both 3 mm thick.  I don't remember what the stated color is.  I am going to fire it with the firing schedule stated by Delphi.  Now that I have the correct thickness hopefully it should work.  The uneven edges of the previous work fused on this mold was probably due to not enuf glass.  When I sprayed the mold this one time I held the spray for a few, perhaps several minutes over the allotted 6 minutes in order to make sure that it would work.  This time if there is devit or uneven sides I will know that it is not due to not enuf glass. 

The last one I did stuck to the mold, I think it was because I did not spray it long enuf and I wiped it with a cloth before firing on it.  Hopefully this one will release.  In order to get the glass to release from the mold, I ramped the kiln up slowly, 150 degrees until it reached 650 degrees and then let it cool naturally.  That did not work but I was able to pry the piece from the mold instead.  Of course in doing that the glass took a small chunk of the mold with it.  But I think I can continue to use that mold, not making a piece that covers the whole mold but a smaller one that covers only a partial segment of the mold, the part that is not missing a chunk.  Any way I will use the following firing schedule on my experimental piece:  300 dph.......................1360 degrees........................................hold 10 mins.  300 dph.....................................1465 degrees.........................................hold 5 mins

Full...................................900 degrees........................hold 1 hour

100 dph.........................................700degrees..........................hold 2 mins