that piece is great! great use of color and mixing colors. and design too. though i work on a much smaller scale than you, i alway put a slight dome on my metal before enameling. one of the things this does is to give the form some strength and inhibit warpage. Once one of my pieces starts warping (usually a long thin piece or one with thin protruding points), i will wait until the top enamels layers are close to the top. then i pull the piece out of the kiln, and while it is still hot, flip it over and into a unenameled copper ashtray that has a similar dome. very carefully but quickly, i use my kevlar heat resistant (i wish) gloves to push from the back and redome the piece to the shape of the ashtray's dome. after it has cooled and i check to see the new shape, i may touch it down from the front while hot using a small spatula/trowel tool. i would be too worried about ruining my wires to try any type of reforming while the wires were exposed  in the early stages of the layering process. hope this helps. 

So as Ricky wrote slight doming of the metal is the best antidote to warp of enamel plates. The dome must be only little Millimeters in height. Other advantages: curved work pieces are much more stable than flat plates, they are much better to grind; slightly curved work pieces are visually more pleasing.

Anneal the work piece plate and place it after cooling in a wooden dapping block.  With a rubber mallet, the plate is driven into the depression. (Dapping blocks see here: http://www.ottofrei.com/Wood-Dap-And-Blocks/ )

Anneal also the brass- cloisonné wires before use. It is not necessarily required the wires before using to pickle. The cinder does not interfere with further processing.

To adapt the curvature of the wires, they are pressed against the laying upside down into the wooden depression.

Edmund

Thank you so much to replying, Ricky and Edmund. I really learned alot from working on this piece.

I was trying to keep the panel flat and was pretty successful, but while stoning it realized that may have not been a good thing. The copper ashtray trick sounds good to me for working the piece hot, and the wooden blocks are the only thing that are going to be big enough to work on something this large. I have the metal daps and block, but that's for much smaller pieces. Placing the wires in the block for forming is great advice.

Believe it or not, I made a block years ago for a sea shell that I formed, now if I can just find it...

Thanks to both of you for the help!

Debbie

Hallo Deborah,

Oh, I forgot. If it is necessary to hold a workpiece flat, do the following:
Take the hot piece out of the kiln, remove it from the trivet und put it onto a flat fire brick-plate.
Let cool down the work piece a short time until the red color from the heat  is gone.
Put a second fire-brick onto the surface of the work-piece.
Put immediately onto the brick an heavy object like an anvil, a flatiron or if you don't have an heavy object, use a cooking pot with water.
Let cool down the work piece until it is hand-warm.

Edmund

I was working on the pansies piece that I posted, which is 3.5 inches wide, and had to fight warpage with the piece every time it was fired. I was putting it on a steel plate on top of the kiln and putting a flatiron on it to flatten it. I think if I had been using anything lighter than the flatiron, the warpage wouldn't have flattened out. The first few firings, some of the wires would bend over, and I was continously trying to straighten them out before repacking. After the glass got up high enough it wasn't an issue.

Should I be doing things differently? How do you guys deal with this sort of problem?

Debbie K