Military production question

[Torgonius]

I'm relatively new, and it seems like adding factories to a production line is very much a lesson in diminishing returns.

Is it really more efficient to have 2 lines of 10 factories each going for the same item than it is to have 1 line of 20 factories? I have not yet taken the time to test it out, but I figured I'd ask in case someone else has.

[CaptainSpacetime]

There’s no difference.

But separate lines you could change one to the upgrade while keeping the old one on full efficiency.

[Torgonius]

Thanks! I appreciate the feedback.

[drewbstar]

It’s better to have 1 production line of 20 factories. Certain countries have bonuses or maluses to their production cap and tetention, but at the fundamental level it’s better to consolidate.

It gets better with research, namely the dispersed industry research. This research will help you retain your efficiency when updating your production lines.
Researching the production (left most) will raise your cap, which will also help.

[mk11]

Behind the scenes, production efficiency is tracked for each individual factory. Separate lines mean you can make better use of production retention when changing product for just some of the factories. They also give flexibility in determining what factories to lose when factories are lost to advancing enemies, as a result of political changes, to resistance or enemy bombing, for resource shortages, etc.

In terms of actual production there may be a marginal rounding advantage in consolidating lines. There is though a QoL advantage in having fewer production lines.

Note that this is for army and airforce production. Navy is different in that as there is no production efficiency you can always move dockyards from lines without cost so fewer lines is almost always worth it.

[johnknott]

Apologies if this is well known or not what you wanted the advice on but it is relevant.

When you get to produce the upgraded version of a thing because you've got the tech (be it artillery or especially infantry equipment and fighters) DO NOT just switch the outdated equipment to the new one on the same production line.

Obviously it's going to vary on the situation but if you're in the middle of an armed struggle (rather than pre-war) you definitely don't want your infantry equipment's output to suddenly drop (which it will dramatically if you just switch).

Suddenly you'll be getting through equipment faster than you can replace it, your stockpiles will run down and before you know it you'll be in a world of trouble. Divisions in the field on low strength and you can't train anymore. Particular problem for countries like China.

Set up a new production line for the new equipment (perhaps with a few factories taken off the old) and as it's efficiency and output rise, start switching more over until you can get rid of the old production line completely.

As China I once had three versions of infantry equipment going at once just so I could keep my enormous manpower equipped.

This can also be a huge issue with aircraft. Keep the old lines going (as they often were in real life).

Britain in 1940 is a good example. The Luftwaffe are about to come over in large numbers but if you switch your Hurricane line straight over to Spitfires, they'll get shot down faster than they can be replaced. Keep producing the Hurricanes. In RL Fighter Command had more aircraft at the end of the Battle of Britain than they did at the start. You want to keep it that way.

Germany needs to do that over Barbarossa for most of it's aircraft for similar reasons. The Soviet air force is always bigger than you think it'll be.

[Mack]

I disagree with people who say "keep old stuff going". You can't just magic the factories for the new item out of thin air. You're going to lose something in order to have two lines going at once (by removing existing factories on other items), or you're going to have to wait until new factories get build, which is just introducing even more delay.

If you're in such a brutal deficit that you can't afford the few months it takes to regain efficiency because it's costing you the ability to keep your units supplied, or to build new units to hold the line, or hold the air, then you shouldn't be thinking about upgrading anyway, just adding more factories to the things you need to get your production in order.

[TasteDasRainbow]

Originally posted by Mack:

I disagree with people who say "keep old stuff going". You can't just magic the factories for the new item out of thin air. You're going to lose something in order to have two lines going at once (by removing existing factories on other items), or you're going to have to wait until new factories get build, which is just introducing even more delay.

If you're in such a brutal deficit that you can't afford the few months it takes to regain efficiency because it's costing you the ability to keep your units supplied, or to build new units to hold the line, or hold the air, then you shouldn't be thinking about upgrading anyway, just adding more factories to the things you need to get your production in order.

This is generally why you split production lines into multiple lines even for the same good, alongside also creating variants, improvements, etc. That way you can upgrade half of your production and give it time to organize production efficiency, while still maintaining half production on prior versions until that new product reaches production efficiency on half of the factories.

[drewbstar]

Honestly, I’m just lazy when it comes to production nowadays. I’m rarely producing at a point where min-maxxing lines really makes a difference. I’d much rather change one line of guns once, rather than manage two or three lines and slowly switch factories over which requires me to go back and manually adjust them repeatedly.

[mk11]

If it matters enough it is worth using division equipment selection to keep low priority troops using the old kit while the more important divisions move to the new equipment. If you want to get fancy use a template for recruitment and initial exercises that only uses the old stuff.