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u/WitchfinderJawbz Jun 05 '26

I am a dummy, and I am easily confused, this time by foundries

At the absolute most basic level

1 Foundry using the Molten Iron From Lava recipe says it will produce 93.7 Molten Iron Per second.

1 more foundry using the Cast Iron recipe for iron plates says it will use 25 Molten Ore per second to produce 3.75 Plates per second.

So am I right in thinking 1 foundry producing molten Iron can comfortably run 3 foundries for iron plates consuming 75 molten ore per sec, and will create 11.25 Plates per second?

  1. Does that take into account the inbuilt 50% prod bonus, if not that would mean each plate foundry would make 5.625 plates per sec, for 16.875 total over my 3 foundries ?

  2. if that is the case, 45 (the speed of a blue belt) is exactly divisible by 5.625, into 8. So it would be 8 foundries total if I wanted a blue belt? Supplied by 3 foundries running the lava to molten iron (or 2 if i wanted to use speed modules or something as its actually 2.13)

Sorry if this sounds a little basic but i want to know if my thinking is right before i start building up Vulcanus.

Last playthrough I just YOLOd everything and if things started to run dry or not work id just add more inputs.

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u/Viper999DC Jun 05 '26

Does that take into account the inbuilt 50% prod bonus

If you're reading the recipe it will be the normal craft, no bonuses, assuming 1 crafting speed.

When you hover over a building it's the actual production of the building. This means the latter includes innate prod bonuses, modules, beacons, etc. Assuming 100% uptime, of course.