Kiln Dam Half Set - 21"
Purchase this 21" half-set, containing two 21" double-layered dams.
You must order two half-sets to purchase one complete set of dams. (Of course, you can order more than two half-sets - perhaps a 10", 15", and 21" half-set to give you even more flexibility over the size of your work).
Half-sets allow you to mix and match sizes, based on the size of your kiln and kiln shelf. Each half-set contains 2 pieces of smooth ceramic, and 2 pieces of larger, heavier firebrick. So when you order two half-sets, you'll have 4 pieces of smooth ceramic, and 4 pieces of heavier firebrick to put behind it.
This double-layered dam system provides the best outcomes for your multi-layered glass artwork, or for thicker frit-based compositions. It minimizes coldwork to nearly zero in multi-layered work - in most cases your final piece will need only a few minutes of minor clean-up with a hand pad.
Because kiln sizes vary, you can purchase these dams half-sets in various sizes. Dams should generally extend 2" (or more) beyond the edge of the glass. So for an 8" x 10" glass project, you could use a 10" half-set and a 12" half set... but you could also use two 12" half sets and the dams will extend a bit farther on two sides.
Note, however, if your dams are too much longer than the glass, they may extend out so much they no longer fit on your kiln shelf!