Spring Firing Results, Organizing, and Underglaze Color Reference Tiles

I have now fired thrice in the last six weeks, meaning I've been eking out time in my studio to glaze and weekend time to load and fire. The firings have been fairly dull so far; just some low fire odds and ends that had been waiting since last summer.

This is a staged shot, I forgot to actually snap a picture when I was unloading the kiln.

I have a new small kiln that my parents brought me from a friend in Wisconsin. It doesn't have more than one shelf at the moment, but I was able to balance a large domed piece on stills in place of a shelf and thus fire, essentially, two layers of work. 

This is the real firing, after I pulled out the dome piece.

The dome on stilts fired just fine, but either the entire kiln or just some of the pieces under it wobbled at some point, probably when I was closing the lid, and fell off their stilts and into one another. 

Oh no, those red pieces are stuck together!

One small piece fell of its stilt and just glazed itself to the stilt. After unloading that kiln, I realized that it would be beneficial to reorganize (by which I mean organize for the first time ever) my fairly massive stilt collection. 

And that weird purple thing is also stuck to the stilt.

That I have so many stilts is mostly a function of how I got the kilns and partly a function of another  donation of stilts from a now forgotten source. Some of them are great, some of them are not, but I think I've only ever actually purchased one small container of metal stilts.

So many stilts, now sorted by size and type.

The size of my stilt collection is roughly the size of my underglaze collection. After sorting the stilts (with some help from the kid) last weekend, this weekend we sorted the underglazes. Sorting my underglazes consists, in large part, of consolidating half full and mostly empty 2 oz jars  and rehydrating quite a few of them. I have purchased numerous 2 oz jars over the years as portable sample sets and because some colors don't come (or didn't used to come) in pints. Unfortunately the pints stay liquid much better than the small containers.

Duncan Cover-Coat Underglazes

I have two different brands of underglazes (and a few odds and ends). The Amaco Velvets are my faithful standbys and what I use most of the time, but I have full box of Duncan Cover-Coats, too. The Duncan line has some colors I like and they are generally cheaper, but I've had a few instances of peeling underglaze in the last year and those seem mostly to be the Duncans. The Duncan 2 oz jars are great for pouring out glaze, but terrible for this weekend's consolidation project, as the neck of the bottles narrows, preventing a tool from scooping out the extra stuff. 

    

Amaco Velvets and Liquid Underglazes (sorted into warm and cool boxes).

After consolidation, I took a full inventory of my underglazes (and the extra precaution of labeling the lids or easier identification in boxes) so I can replace those I am missing. A few years ago I made some reference tiles for my underglazes. I painted the number of each glaze (the numbers are short and easy to find when reordering) and lines with three different thicknesses of application onto bisque tiles. I then striped one section of the tile with clear glaze and fired them. These tiles are a handy way to check which glaze I used on a fired piece, since wet and even dry glaze doesn't always look the same before and after firing.

Some of my underglaze reference tiles.

With these tiles, my consolidated and labeled bottles, and my inventory, I was quickly able to determine that I am out of Amaco Velvet underglaze V-372 (Mint Green). I needed to determine this because last year I inexplicably used V-372 it on most of the bottom of a piece, but not all. Then I fired it so that it is permanent and promptly forgot what I had done. Now I have to fix it, but at least now I know what I need. 

  

Stilts

I've fired several kiln loads of work over the past few weeks. These loads have consisted mostly of small pieces with no base and therefore no logical ending place for the glaze. When I apply glaze on all sides, I need to stilt each piece so that the glaze won't melt and stick the piece to the shelf. 

stilted pieces in the kiln after firing

Most of my shelves have kiln wash on them, meaning they've been coated with a layer of material that keeps glaze from sticking to the shelf. If I were to get glaze on the bottom of a piece, the glaze would melt, stick to the kiln wash and later lift off the shelf easily with a bit of kiln wash on the bottom.

checking the fit of the stilt before loading into the kiln

If I put glaze on the bottom of a piece that is loaded on an un "washed" shelf, the glaze will melt, sticking the piece to the shelf. Removing the will take a bit more effort, and may result in part of the piece sticking to the shelf and breaking away from the piece, or vise versa. Glaze on an unwashed shelf usually results in damage to the piece or the shelf.

four point metal "jacks" stilts and a variety of ceramic stilts with metal points

To prevent damage to the piece from kiln wash and to prevent damage to my unwashed shelf, I load these small, bottomless pieces on stilts. I have a wide array of stilts, including metal pointed stilts with three or four prongs and some four-pointed metal stilts that look a bit like jacks. I can arrange pieces so that they each have a stilt or two or three. More points of contact between the stilt points and the piece makes the piece more stable and less likely to tip off the stilt during loading or firing.

the white spot is where the glaze melted to the shelf after this piece rolled of its stilt during firing or loading

After firing, the glaze has melted, but, assuming the glaze hasn't run down past the point of the stilt, the metal leaves a tiny hole in the glaze that is more or less invisible. If you look carefully at "China" dishes that have a shiny surface inside and on the foot, you can see three or four tiny holes in the glaze on the bottom. These holes are the marks of the stilts used to hold up the pot in the kiln. If your dishes have a matte surface on the bottom, but are shiny on top, they were "dry footed" during the firing and never had glaze applied to the bottom so that it wouldn't melt during firing. These pieces didn't require stilts to keep them from melting during firing.