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Will some Super Spray added during fire polish be satisfactory to fill the tiny holes I'll make when I drill out the tiny bits of lid crud dropped during firing? My Skutt clamshell just started dropping bits of kiln brick when I started making larger, thicker, more complex pieces. You know, the ones where you really don't want things to go wrong. I want to avoid full fusing these pieces again.

Define "tiny."

You've got to take SS up to 1425° (I believe) in order for it to fully fuse. I used it on some piece I tack fused to 1400° and it left a splotchy-blotchy mess.

How about clear powder instead?

Morganica - "tiny" being a range from an average fine size frit to a large medium size frit. Each of the 3 pieces of glass is about 17" X 19" Roger Thomas style landscape. They might even go unnoticed by anyone but me.

Valerie and Laurie - I wanted to avoid another full fuse since I had some difficulty getting dams situated on the pieces. I went to the limits of my shelf and had to do some creative rigging which left me with edges to cold work. I was hoping to cold work then fire polish with a flux-like filler for the drilled holes.

Hmmm. Those aren't really very tiny. They might be unnoticeable because the SuperSpray makes them as shiny as the rest of the glass, but you'll still have pits. SuperSpray coats; it doesn't really "fill."

The problem with firepolishing is that it happens after slumping--the surface of the glass must soften and move enough to gloss up the glass. I doubt the glass will move enough to be a problem with a standard firepolish, but to soften the glass enough to fill in bigger holes, it'll be moving and might spread a little bit, or at least round over. That might not be a bad thing.

The other option, if you're drilling these things out, is to confine your coldworking to as tiny a space as possible around the flaws, get it as smooth as possible. I get a dowel or something else with a round, flat bottom, wrap a piece of very thin packing foam around it and a piece of wet-dry sandpaper around that, and take the "volcano" around the pit back down to level with the rest of the glass.

Once you've done that, you can either firepolish (with or without the SuperSpray) and accept that your piece might flow. Or you can apply a light coating of CleanShield to the glass to gloss up the coldworked areas and not fire it at all. Rub it in well.

Hi Vonon,

I agree that Super Spray will not give you the fill you need to heal these pits. I suggest filling them with frit/powder and firing to at least a contour fusing temp.

I sympathize with the limitation your kiln shelf size imposes (I have this kiln too). It may not be relevant to this discussion, but you might want to look at alternative dam materials. Ceramic dams are usually bulky. To maximize usable shelf space on my Skutt Clamshell, I use stainless steel bars 1/2" x 1/2" as dams and have had great success with them. It takes a lot of glass to move a 1/2" cube of SS

I'm sure your final work will be beautiful! Please, post pictures!

Sharol

"To maximize usable shelf space on my Skutt Clamshell, I use stainless steel bars 1/2" x 1/2" as dams and have had great success with them. It takes a lot of glass to move a 1/2" cube of SS "

I have the same kiln, may I ask, where did you purchase those?

Thank you,
Shereen

Hi Shereen,

I bought the stainless bar through OnLineMetals.com. I bought them in 3 ft and 4 ft lengths (for shipping) and then cut them down to the sizes I wanted. In addition to damming, they come in real handy for aperture and wire melt supports.

Sharol

Thank you for such thoughtful replies. I have to grind the edges since there are rough spots from contact with the dams/fiber paper so I will also use my Dremel to drill out the brick fragments and then fire polish. I'll use the product Cynthia mentioned to make the drilled areas shiny. This way I'll avoid a full fuse with attendant possibilities of more debris falling onto the pieces. The debris happens to be located in the portion of the landscape that portrays grass and weeds so I don't believe it will be noticed. This is for wall mounting in my own home so I feel I can be more accepting of flaws. For future pieces I will have to determine what is causing the bits of brick to fall during the cool down. After the first piece I re-secured the pins that hold the coils along the front edge and lightly brushed the brick but still got debris. One problem might be the fact that the peephole located on the front edge of the lid makes that portion of the brick pretty narrow in places and after having to reattach the pins earlier may make it more vulnerable.

Thank you again