I have been doing some dichro cabs with some success - learning as I go with help from this board
my last two batches have come out with some puzzling results and I don't know what I am doing wrong or how to correct it - any help greatly appreciated!
This is the problem - I am firing dichro on an assortment of backgrounds - all reg thickness - they come out of the first firing looking great - then when I refire putting on the clear cap they really flatten out and the ones on black background all end up with black blurry edges - has anyone else ever experienced this?
Also when I refire some of the colors really change - am I firing too hot when I put the clear cap on? I normally go to 1480 degrees.
my next batch I am going to not hold at all and see if that helps
If anyone teaches dichroic classes near Wisconsin would you please email me?
Is there a reason why you are doing two separate firings rather than firing once with the clear cap in place? Since these are cabs (translation: very small pieces) my guess you are firing too hot and/or holding too long, particularly on the second firing.
My simple cab construstion consists of black base, dichroic or other design pieces and clear cap, often with fiberpaper inserts to make an opening for a chain or cord. These are fired in a contollerless Neycraft burnout oven (you work with what you have!) to about 1480-1500 and then I follow the Brock Craig School of Looking at Your Work to Determine If It Is Ready: I literally peek at them a few times until I see the top glossy and the edges rounding--usually takes about 10-15 minutes at that temperature, then crash cool to annealing temperatures. I believe it is generally accepted that pieces the size of cabs are less temperamental in their reaction to temp/time than larger fusing constructions--anyone, please correct me if I am wrong.
a couple of suggestions/comments. First -- and just checking -- do you know that the dichro colors will come out differently after firing than the way they look beforehand? Second, try putting the cap on the cab in the first firing. When I make cabs out of scrap dichro, i usually have a black base, either thin or regular thickness. i lay up little junk pieces of dichro such that i get a good bottom layer, then arbitrarily stack more on top. i should mention that all the dichro i use is on a clear substrate, not on a black substrate. that black substrate is possibly the source of the muddy edge forming in the second firing. Anyway, after stacking up as many colors as i feel i want, all little fragments, all of them coated side down, i then lay a piece of thin clear on top (no dichro coating), or sometimes a thin clear violet dichro, coated side down. This gives the top of the cab the smooth surface. If you use violet upside down, it enhances the opalescent appearance of the cab. Putting the clear cap on top in the first firing eliminates the need for a second firing. You should see some of my cabs before firing ... they look like junkpiles or haystacks, but they reduce to a nice-looking cab by the time they get to about 1500 or 1600, and pretty round, too. i usually eyeball them around 1500 to see how they look -- with UV goggles, of course. Kitty.
there's lots in the archive about dichro. the type of dichro you are using could also be a factor. lots of people don't like dichro magic because the colors tend to burn out during firing. this could be why you are getting muddy colors. also i agree that you should be able to do all layers fired in one firing. try making the top clear coat a little bit larger than the other layers so that your edges are smoother and cleaner.
I started about a month ago working with dichro. I began with a pound of scrap from CBS, but a couple of weeks ago I ordered several quarter sheets from my art glass supplier.
I too place my dichro pieces on a solid color base (and sometimes a clear base) then cap it with thin clear. I do most of mine in a little table top Paragon QuikFire. In this little kiln I fire to about 1550-1600. If I'm filling in space in my larger kilns I fire to 1400. This is all with Spectrum 96 glass.
I thought glass was addicting, but dichro is really addicting.
I am confused. (not unusual.) The teacher for the fusing class I took told me I would get lots of bubbles if I tried to sandwich multiple bits of Dichro between two layers.
This of course is just what I want to do when making small cabs, so if it is not going to be a problem I would be very pleased.
WOW! thanks so much for all the suggestions! I had gone to 2 firings to get away from the bubbles that were bothering me. But I will retry putting the clear cap on and doing only 1 firing. I use mostly (90%) CBS dichro - but have just recently started using the clear.
There is so much to learn and I have to agree with Judy that
Dichro is addictive!
Are any of you willing to share your firing schedule with me? I am going 400 degree to 1000 hold 10 minutes then afap to 1480 with a 15 minute hold and let the kiln cool on its own. Does that sound about right?
Also, I don't know if I dreamt (sp) this or if this is true - Is there such a thing as dichoric frit? and does anyone know who carries it if it is available?
[color=red][/color] I'm new to dichro fusing & am confused about how to set me digital orton controller. I have a jen- kin kiln w/ this controller & would like to make some clay molds to then use w/ my dichroic glass (bullseye 90 coe). Can anyone help me from start to finish w/ this? the clay i am using is white talc & I don't even know how long to fire the clay much less the glass once it is in the fired mold. Can someone give me some direction & help w/ this confusing controller & a firing schedule for the clay & glass? Any help will be greatly appreciated!!
Here's a spot ... http://www.lincolnglass.com
and search for dichroic frit. I believe you will need to set up an account with them though. Their 2 oz tube of frit is $28. They also have good prices on thinfire!
the cabs i make are composed of many small pieces of dicho, sometimes with a clear cap, fired all at once. i don't get bubbles, probably because the pieces are all very small, and jewelry in general is small, so other firing schedule rules don't apply. i use Klyr-Fire to stick all the bits together. when i get a shelf load, i put it in the kiln and heat it up to 500F over about 20 or 30 minutes. the purpose of this initial ramp to 500 is to burn off any liquids. after that, it's Bat Out of Hell, as fast as possible, to somewhere between 1500F and 1600F, depending on appearance. natural cool-down of kiln provides sufficient annealing for jewelry pieces.
CBS makes the dichroic frit. the 90 COE is uroboros clear, of varying thicknesses and dimensions, with dichro covering more than half of the chunks. It is NOT like other frit, and mostly needs to be capped. before buying, try to obtain a sample first, or only buy one tube so you can try it before you commit more $$. dichroic frit is not uniform in size, and is not like glitter or fairy dust. it is more chunky, sharp edged, different sized, and needs a second firing of the clear cap because it produces a rough texture. i don't think it can be successfully capped on the first firing if the chunks are biggish because of bubble problems. for my purposes, i find that cutting up dichro into tiny bits by hand works better.
i got a new paragon today with an orton controller. if you don't get some advice about that in the next day or two, i can probably tell you how to program it. my other paragon has a different controller, but i think they operate in similar ways. good luck with everything. kitty
