you can let your factory work at 100%, set the slider at 100%.

if you put everything at 33% than your factory's will only work at 33% there capacity, same goes with research and with buildings up your planets.
its not possible in this game (kinda strange but good for strat) to have all your factory's and researchlabs work at 100% at the same time even though your economy might be big enough (i think they done this to prevent human players to get ahead to much on the IA cause we tend to build a big economy, atleast i do )

Smitty,

Think of it this way.. Military is spent only on constructing SHIPS, Social is spent on constructing BUILDINGS. Labs only do RESEARCH. Basically, all the Individual sliders do is proportion the amount of (milit/social) money that generates MPs (manufacturing points) that are 'spent' each turn. Research is spent in labs to generate RPs (research points).

So lets suppose you have enough factories to produce 50 MP and enough labs to produce 30 RPs. Further, we'll say your spend rate is set to 100%, and is divided 20% Military/ 30% Social/ 50% Research. This would give 20 MPs for constructing a ship, 30 MPs for constructing Tile Improvements, and 15 RPs from your labs.

Where it gets complicated is when you start calculating BONUSES. Bonuses are charged at 50% (half cost). So lets say you build a factory on a 100% manufacturing tile. Your factory (w/o bonuses) produces 7 MP (at 7 BC). On this tile though, it will produce 14 MP (at 11 BC). It's further complicated by racial and govermental bonuses (also at 50%).The actual formula is in the wikipedia.

All the SPEND RATE does is determine the overall Manufactering and Reseach Rate that your factories/labs will produce. Because it cost BCs for each MP and RP, the spend rate allows you to 'under-run' your factories and labs to save some BCs. Say your TOTAL factory capacity is 200 MP, at a cost of 150 BCs. And your Labs provide 100 RP at 75 BCs. Your spending 225 BCs a turn for that. If you cut the spend rate to 50 %, you will genarate 100 MP and 50 RP for 113 BCs. In addition, Manufacturing cost have a limit, based on the total number of factories in your empire. Research is similary restricted by the total number of labs. This is INDEPENDENT of your taxes, colony, military maintenance costs.

So be careful not to build too many factories or labs, as this can and will kill your economy. Instead, try to build as many trade/banks that you can fit, along with morale centers and the occasional farm. Watch your tax rate, and plan big purchases accordingly.

I play on large galaxies on painful and there is generally a period in the early game, after the colony rush, where I have to set my spending slider to less than 100% for a while - sometimes as low as 50%. Generally this is because I have at least one factory on too many planets with no financial infrastructure to support the spending. However, you need a factory on a planet to do the social building so this result seems inevitable. On a good game it might only take me a couple months to recover and move my spending slider up near 100%. On a game that I have managed to over expand or maybe carelessly built a factory on a 300% tile, it can take me up to 6 months or longer to recover. I would assume that everyone has the same issue, but if you don't I would love to know how you avoid this problem. Once I get trade started I never have money worries again, but until then it can be a very tight thing. Also, until fairly late in the game I don't actually keep my spending slider at 100%. It is almost always more cost efficient to be at 99%.

Rripper, thanks.