Alternative to Glue

Frit

Yes, clear fine frit can be a risk free alternative to glue.  Glue is to keep things in place while moving to the kiln.  Fine to medium grit can do that too.

Glass is pretty heavy and if you move the piece carefully the frit will not move and its weight will keep the other glass pieces in position.  It is better, of course, if you can build in the kiln.  Then you add the frit at the last moment to keep everything in place during the firing.  At rounded tack fuse the clear glass frit will become part of the surface. 

This method will not work for everything.  If you are using laminating or only softened edges for your tack fusing, the glass frit will remain granular.  If you have to tip or manipulate your shelf into your kiln, this will not work either.

This note indicates the use of frit to stablise stringers and rods.

Using frit to stabilise your pieces is yet another way of reducing the amount of glue usage in your work and so reduce the risk of bubbles and marks, even though the practice is not always applicable.