Choosing a batch size

Batch size here is decided by how long the wax stays in its pour range, not by how much you can melt.

The pour window sets it

A wax has a recommended pour temperature range, often ten degrees wide. Outside it you get wet spots at the cold end and sinkholes at the hot end.

Pour fifty vessels from one pot and the last ones are poured at a different temperature from the first, which means the batch is not one batch.

Which is why makers with a large melter pour into several smaller pots rather than working out of the tank.

What sets the floor

Weighing accuracy for fragrance. At 8 percent of a 500 g batch that is 40 g, which any scale handles. At 8 percent of 100 g it is 8 g, which is fine, and dye at 0.2 percent of 100 g is 0.2 g, which is not.

So small test batches are reliable for wax and fragrance and unreliable for dye, and a colored test batch should be larger than an uncolored one.

A practical number

Enough for one pot-load poured comfortably inside the window: often 10 to 20 medium containers.

Scale by repeating rather than enlarging, until a pouring method changes the window itself.

Two pots staggered, one pouring while the other comes to temperature, roughly doubles throughput for the cost of a second pot.

Batch size and cure

Candles need one to two weeks of cure before they can be judged or sold.

That turns batch size into a cash and space question: a run is not sellable stock for a two weeks, and it has to sit somewhere at a stable temperature while it waits.

Plan production two weeks ahead of demand, which is a useful piece of scheduling in this craft.

References