raku should NOT look like this
 

My surprise when I opened the kiln. All my raku on red had not just cracked, they had presented themselves on the half-shell, so to speak.



Any insight on what I did wrong would be great. I made them by
-make a round with red
-encasing red
-rolling in raku
-oxidising flame
-quick cool with marver
-encase once more

My black beads do not split and look fine, but I only encase once. Why twice for the red? To avoid the darkness the raku brings to the bead. Can't see it when I use black as my base but ruins the red when I place the raku without encasing first. Obviously it is the double casing, but why? I am using COE104 effete glass and clear.

It was not the raku most likely, but encasing the red.

If you want to encase red, try a clear core, encase with red, then encase with white.

Is the raku 104 or 96? Honestly those look thermal to me though

It looks thermal, but reds, oranges, yellows don't necessarily encase well. Like Eileen said, make them with a clear core. They are much less likely to crack.

Thanks for the reply Eileen. Seems I remember now reading about using a clear base, but for some reason I thought perhaps I was special. Or when mixing different manufacturers of 104. Anyways, I will give your suggestion a try.

Kathy; I am using the 96 octane. Have read it should not be a problem as long as I do not exceed 10% and I am sure one roll in the raku would not come close to that threshold.

No worries though. The beads were interesting but only by so much. I am thinking I can get the result I want with frit.

Cheers

That only applies if you're not encasing. If you're encasing, 1% is too much - don't mix at all.

I never have any luck encasing 96 with 104. But the cracks I get are not along the mandrel either, so maybe it is the red.

The red is 96 but clear is 104 correct? Halved is usually thermal, but I think it's incompatibility in this case.

Ravenesque: All the glass (red and clear are 104) and the raku is 96 powder. So, a marble base of red 104, encased with super clear 104, thin layer of 96 raku powder, then clear 104 again.

Honestly, thats absurd. You invite failure by any mixing outside of families of COEs. Never mix 104 with 96 or 90.

Larry isn’t quite accurate. You can mix 96 with 104 in many applications. Otherwise FritGirl and Val Cox wouldn’t be in existence. So you’re on the right track by keeping it thin and minuscule. But it can be tricky. I would probably not encase fickle colors and use 96 coe at the same time. If you want a design, perhaps add an encased frit or enamel stringer on top of red. No encasement our the bead itself.

I know Kris Shiable uses 96 exclusively in her fit beads because she loves several layers of 96, and lots of frit. But generally speaking Dusty is correct. 5 or 10% works well as surface design but not every single color. Some 104 may be 105/106. Some 96 may be off as well. The viscosity has a lot to do with it, etc. Raku frit on unencased opaque red is gorgeous, try that and not the powder. Julie Nordine uses a lot of both colors in her palette. Though she may use 104 Raku, I think most of us prefer 96.

I agree, lampworkers have been using 96 frits on 104 forever now, myself included.

I see, I was confused by 96 octane, I've never heard of it. Try one with the clear core.
If the red is a CIM color, make sure it's not an "opal", those don't like to be encased.