How many factories = speedy ship building?

As many as possible.... D'oh!

I usually try to make at least 1/2 the squares into factories for those planets I am making into Ship Producters. You just have to have several squares each for Farming, Happiness, Economy and one for the Star Port.

And you can skip the economy (i.e. Stock Markets) on some planets, and load them up on others. It is not important that each planet be in the profit zone. What is important is that overall you are in the green.

As to a number of factories, 7 Industrial Complexes would be the minimum to get ships out quickly. And don't forget to add the Manufacturing Capital building and Hyperion Shipyard (if you can find room for the shipyard, +1 speed bonus is not all that much if you are up to HyperWarp engines) on the world that will be cranking out the most and/or largest of your ships. And a few loaded up econ starbases around that planet would help production quite a bit.

5 factories per planet is a good rule of thumb, if u have a 300% manufacturing bonus then 2, 100% then 4 etc.....
Gives u very balanced ship building. Later on in a planets development when its built everything, upgrade them to other buildings. Works for me.

I have noticed that the speed of ship building is dependant on the amount of factories that are built. I was wondering what the amount was for very fast building?

Have you also noticed that planet improvement building is also dependent on the amount of factories? In case you weren't aware, they give you a production bonus. These production points are alotted to either military or social production, based on the sliders in the domestic panel screen.

I usually have 5-8 on a planet that produces ships. 10 is really nice, and if it's a manufacturing capital you have a choice of really churning out those ships, or reducing how many factories you build.

i always use 3-4 factories on each planet and let most of them produce constructors (and their social stuff, mostly neutral learning centers )
my manufactoring capital then has starbport, capital, omega shipyard and then factories only (no entertainment stuff, 5bill ppl can be happy without it)
i surround it with 4 fully loaded econ starbases and then it can produce my whole fleet
all other planets only do research and produce constructors
i mostly play galaxies with about 10 planets per player and i tend to go neutral + alliance or tech victory

works fine for me

I think it depends on galaxy size. When you have a larger galaxy having one big producer is not enough. On a medium galaxy you can rely on one. Lately I have been playing huge galaxies and I find that I have to mix the number of factories to get the most out of each planet. Generally I have a couple of production planets. They have a farm or 2, social, capitol, and the rest industry. The ship build techs are great and all but I would rather have the extra production.

4-5 seems enough in general.

My last game I had a tile with 700% and one with 300% bonuses to manufacturing, it was awesome

It could spit out tiny fighters with 3 attack and 1 defense every turn, most other things in two turns. And that was without having a focus.. place ended up with no research at all though, I had to level my non factory buildings to make room for galatic achievements that were being completed in 8-10 turns, I got the micro repair bots, the uppity ship hulls, diplomatic translators, that fancy space fast food joint, and maybe two other achievements all crammed on to that planet.

I use 4-5 just to build the planet, then 6 or more for a ship-building planet. Of course, bonuses help.

I always start off with ~1/4 to 1/3 of a planets tiles with factories in the early game phase, when I am focussed on building colony ships, constructors and Social buildings. I base the next set of buildings on the available bonus tiles. If a planet has 2 research bonus tiles, I will tend to make this planet a research only. where there are no clear cut bonus advantages, I will take a more balanced approach.

When the majority of planets are taken, I find the 3 with the biggest PQ values and make each one a 'capitol' for that branch of my empire. I take a couple of mid sized planets (12ish or so) and fill them with farms and entertainment buildings to get the populations up for tax purposes. If I start falling behind in research or if my cashflow goes negative, I will start concentrating on building new or replacing old ones that will generate the needed points.

In one game I had possession of 3 PQ 26 planets, I maxxed out each with its own type (one Factories, one Finance, one Research).

Cheers,
Reaver

My starter world gets 5 factories. That produces my custom colony ships at a rate of one every two turns.

I usually research 100% to get better engines, and during the turns it takes to research I buy factories. When I have the better engines, I switch to 100% military, and crank out colonizers.

How many factories? As many as a size 20 world can hold!

Seriously, my ship production worlds are some of my biggest, following right behind the uber-taxation worlds. Plop a shipyard in there, maybe a manufacturing capital, then fill it up. Pumping out 500+ production a turn gets you dreadnoughts in a serious hurry.