I would like to add if you are wet sanding on paper tubes be careful because you can swell paper and ruin the model this way, if you dont like wet sanding because of mess or surfaces that does not like water much (try refinishing and wet sanding a guitar.... the wood would swell and ruin if you got water into a screw hole) use a paper called "fre cut" by 3M. Its basically a coated paper that wont clog and it really makes a difference if dry sanding is needed. I think Home Depot carry them now, its under "Norton non clogging paper" or something, it says that but it really says 3M fre cut on the paper...
If you want mirror finish here is what I would do, prime the rocket, smooth out all spirals and whatever, however only go up to 320 on primer coat, you dont want a mirror smooth primer coat because that is bad for adhesion. If you used lacquer however it will burn in to the previous coat so it wouldnt matter anyways. What you do is spray your color, and give it about 2 coats to make sure you get it all (it sucks to miss a spot after all that clear coating!) then go ahead and spray about 10 coats of clear, do not sand the color coat. Just get a coat, not too wet so it doesn't run, let it sit for one hour then recoat. Get about 3 coats a day, and after your 10th coat let the rocket sit for at least 2 weeks, don't even touch it. Then after that take a 1000 grit wet and dry paper and wet sand it to level the finish, use a sanding block for this, and you can go lower if you want but you risk sand throughs. Get it until all the gloss is gone then take some 3M finsee it II and polish the model with a cotton cloth, it takes a bit of elbow grease to do this. To make it faster you can use a buffing wheel or electric drill with buffing wheel attached to it. Go no more than about 600 RPM or else you WILL burn through. You can also use polish such as those found on
since they are a bit cheaper than Finsee it II, use Perfect it if you wish but it should be good for now, but perfect it will give better shine.
It is VERY time consuming to do this but you will get a rocket that looks so good (like your car!) that people will be staring at it for hours. Dont do this on rocket god sacrifices or competition models... and use lacquer for God's sake! They aren't that expensive and you will have so much less frustration with it compared to cheap enamels. The reason you dont sand color coat is you can sand through (which is bad) and since lacquer always melt the previous coat it is not neccssary since they will self level when you get enough coats on it.