Are there any size limits on the items that a replicator can produce? Has there been shown any different sizes of replicators capable of replicator large objects? What are the smallest and largest things we know to have been replicated?
There are two types of replicator:
- Small ones that will fit inside a Starfleet cabin and is used for replicating food, clothing etc.. These are common and are used extensively, especially on starships were cargo space is at a premium.
- Industrial ones that are used for replicating large components of ships and industrial constructs. As few as 15 industrial replicators are needed to kick-start a civilization that has suffered a planet-wide disaster (this was mentioned in one of the episodes, most likely DS9: "For the Cause" or DS9: "Sons and Daughters" [src]).
There are a couple of limitations in replicator technology:
- Unlike transporters, replicators work at a "lower resolution", (molecular rather than quantum). This limits the amount of storage needed for the "templates" of anything required to be replicated but also means a replicated object isn't exactly the same as the real thing (several characters in TNG and DS9 noted how replicated food/drink doesn't taste the same as the real thing).
- As the object being replicated increases in size, the energy required goes up exponentially, so while building a big enough replicator is feasible, the energy requirements would make it impractical.
Since replicators use molecular resolution, presumably they could replicate anything down to this size.
I don't remember any established or mentioned size restriction, so I'd say it always comes down to some obvious limitations:
- Limited space: They obviously can't build replicators big enough to be able to create a whole ship inside (as they still have docks).
- Limited energy: I assume the bigger your replicator the bigger the required energy (due to bigger distances when arranging atoms and stuff).
As far as I remember they only ever mentioned "replicators" as well as "industrial replicators". The difference is obviously the size and possibly the standard array of available things to create. I also don't think the latter would belong to the default equipment on spaceships, so most crews would be limited to using small/standard replicators. I'm not sure about ships like the Enterprise or Voyager, because they're made for deep space travel, and as such might include an industrial sized one as well to replace bigger spare parts in case the need arises.
Back to limitations:
Considering the beaming technology is considered to be closely related to replicator technology, I assume they've got similar restrictions. As such I assume an industrial sized replicator isn't significantly bigger (available space wise) than the common federation transporter platform. This would probably also fit with the Delta Flier's size mentioned in the comments: Even a small shuttle wouldn't fit inside, but obviously most or all parts as a whole when unassembled. Holodecks seem to be quite a lot bigger, but I think they're not really comparable, considering they don't create matter that keeps existing on its own.
Replicator technology is based on the same fundamental methods as transporter technology, only instead of taking an object, converting its mass to energy and beaming that to a location (in such a manner that it decays back into matter in the same pattern as it was originally, at some predetermined distance), replicators just start out with energy and beam it in such a way that it decays back into some arbitrary, pre-determined pattern of matter.
Sort of skipping step one.
If this is true, then in theory there should be no distance limitations to a replicator. It could replicate something thousands of miles in length, because beaming to a location thousands of miles away is quite routine. Rather, if something prevent replicating such a large object it would not be "size" at all, but the amount of mass. Each kilogram of mass of the object requires something on the order of 8.15E+16 joules, which is alot. It's an almost inconceivable amount of energy (enough to ruin your day if used maliciously). So while the size of an object created by a replicator could be quite large, having enough energy to make such is another thing entirely.
In truth though, there are probably too many Wesley Crushers but with half the IQ running around. You don't want them replicating a 670 meter steel I-beam in their quarters while Lt. Mommy is on watch duty, which could punch a hole through the hull or those fancy windows and explosively decompress the brat. I imagine there are software limitations to replicating objects larger than would fit within the replicator unit.