I do what Randy describes. Pry upward on the low rail, or press down on the high rail, and heat the joint. It should stay aligned once the solder cools.
If one side is too high because solder got under the rail and lifted it a little, just head the joint and press down on the high side with a screwdriver or other something that is not your finger.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Your post says solder instead of rail joiner. Did you install a joiner and solder it or butt the rail ends together and solder?
You have to be pretty deft with a soldering iron to remove a soldered joiner without damaging plastic ties. Easiest way is to lift the track and remove the joiner by cutting out the joint and replacing it with a short piece of rail and 2 joiners. If you are adventurous you can try using solder wick to remove most of the solder and try to slide the joiner off the joint then lift the rail a bit more and slide it off. This usually resuts in melted ties unless you remove them first.
If you didn't use a joiner then solder wick the joint You should be able to get enough of it off to install a slightly spread joiner. Again, this is hard on ties.
If this is a joint between two pieces of track with joiners on the other end it may be easier on both you and the track to pull up the two sections and replace the track or attempt the joint separation on a bench, which usually winds up having the least amount of damage to things.
Late advice I realize, but I got in the habit of running my thumbnail over rail before I hand layed it to check for imperfections. Did the same thing after it was installed to make sure the transition from rail to rail didn't feel bad (I spiked rail in alignment and didn't use joiners or solder) Then pushed a flat car with good trucks and metal wheels over the joint with one finger. It had to feel and sound good before I moved on. You need to baby track when you install it.
Sure, just heat the joint and use a solder sucker or solder wick to remove the solder. You will need a hot iron with a chisel tip, because the faster you can do this the better. Adding a little rosin flux will help with solder wick.
You may not get all of it, but you should be able to get enough that the rail ends will be free for re-alignment.
If that doesn't work, you could always cut a short section out and fit a new piece of rail, with rail joiners pushed on far enough that you can insert the rail and then push the joiner into place.
As I was debugging my new layout, in which almost every joint was soldered instead of using rail joiner, I notice one joint is uneven. This is causing problems with the motive power. Is there an easy or simple way to remove the solder so the rails can be levelled and then resoldered? Would I be better off cutting out the bad section and inserting a section with rail joiners?