Tack Fused Drops

Description of the piece

The enquirer wants to cover some blemishes on the flat blank with clear powder and also tack fuse some additional pieces to a blank to be used for a vase drop.

Reactions

To avoid the grey appearance that often comes from clear powder at lower temperatures, you need to fire to contour fuse at minimum. 

Outside of the requirement for a contour fuse, my experience of making a drop vase with a tack fused blank shows disappointing results.  The temperature used in drops is not high enough to flatten the tack fused pieces.  During the drop formation, the space between the pieces stretches more than the thicker tack fused areas. The thinner glass becomes hot quicker than the thicker areas.

This leads to occasional stretched holes between the tack fused pieces.  The tack fused pieces appear as protrusions above the surface whether inside or outside.  Unless planned very carefully, these elements can be ugly. They will maintain much of their original shape, contrasting with the surrounding stretched imagery.

 

Recommendation

Put the piece back in the kiln and take to a full fuse, or at the very least a contour fuse. This will enable all the glass to stretch as one in the drop, because of nearly equal thickness.  Nearly even thickness is needed to avoid stretching some areas too thin in relation to the rest of the drop surfaces.