For annealing ovens, it is ideal to only have to use one kiln per day for blown glass, unless you make tons of glass. You can measure your glass and find out what size annealer you’ll need to hold a day’s amount of glass. Front loaders make it more easy to use shelves, thereby getting more glass into the oven. If your work will require long annealing cycles, figure out how many days it will take to anneal a day’s work. You’ll need that many annealers plus one. Let us know your available voltage and amperage.