What size propane cylinder should I use?

In the summer months, the Forgemaster forging furnace will operate well on a 20# propane cylinder (the type used on most backyard barbeque grills) with a vapor valve. Propane boils at -44°. Forgemaster forging furnaces burn the vapor that is produced from that boil. Therefore, the closer the ambient temperature is to -44° the slower the vapor is created inside the cylinder. During periods of prolonged use in cold weather you will consume the propane vapor faster than the evaporation rate and you will need to employ a larger capacity cylinder (30-60 lb. cylinders).