Basic gear casting for iron uses 80 molten iron to make 8 iron gear wheels. The advanced recipes produce 11 (sand mold) and 15 (die cast) also for 80 molten iron. This makes sense as it gives an incentive to use these recipes to produce more iron gears for the same amount of molten metal.
However, the same cannot be said for the other tiers of gear casting (steel, brass, titanium etc). All of these have the same basic casting recipe that produces 9 gears for only 40 molten metal but the advanced recipes require 80 molten metal just like iron. This means that there is no reason whatsoever to use the advanced gear casting recipes for the metals other than iron as you will always produce less gears than if you were to just cast them normally.
Basic gear casting recipes for the other metals should all be changed to match that of iron: 8 gears for 80 molten metal.
Edit: Tungsten gear casting appears to be fine and does not suffer the same issue as the other gears, That being said, it looks like 1 tungsten powder mixture makes 1 tungsten plate and 1 tungsten plate makes 1 gear wheel with the already existing recipe. So there's no reason to use the sand casting or basic casting for tungsten gear wheels as just crafting them normally with plates is more efficient. Only die casting produces more gears for the same amount of powder.
Basic gear casting for iron uses 80 molten iron to make 8 iron gear wheels. The advanced recipes produce 11 (sand mold) and 15 (die cast) also for 80 molten iron. This makes sense as it gives an incentive to use these recipes to produce more iron gears for the same amount of molten metal.
However, the same cannot be said for the other tiers of gear casting (steel, brass, titanium etc). All of these have the same basic casting recipe that produces 9 gears for only 40 molten metal but the advanced recipes require 80 molten metal just like iron. This means that there is no reason whatsoever to use the advanced gear casting recipes for the metals other than iron as you will always produce less gears than if you were to just cast them normally.
Basic gear casting recipes for the other metals should all be changed to match that of iron: 8 gears for 80 molten metal.
Edit: Tungsten gear casting appears to be fine and does not suffer the same issue as the other gears, That being said, it looks like 1 tungsten powder mixture makes 1 tungsten plate and 1 tungsten plate makes 1 gear wheel with the already existing recipe. So there's no reason to use the sand casting or basic casting for tungsten gear wheels as just crafting them normally with plates is more efficient. Only die casting produces more gears for the same amount of powder.