In my last post, I promoted an idea for avoiding track cleaning by Joe Fugate, publisher of Model Railroad Hobbyist Magazine. Another idea of Joe's that I have found extremely useful pertains to applying ballast around turnouts, in particular around the moveable points. In this area, it is critical that no adhesive or ballast gets in between the moving parts.
The solution is to apply full-strength adhesive between the ties using a micro-brush. In this way the adhesive goes where you want it and not where it would go if it was watered down in the way ballast cement is applied on the rest of the track. Once the adhesive is in place simply scatter ballast on top and leave it to dry. Once dry, vacuum away the loose ballast and you will be left with ballast in only the places you wanted it and not stuck to the moving parts. Ballast can then be added to the track either side of this area, wet with isopropyl alcohol or "wet water" (water with a few drops of dish detergent to reduce surface tension) followed by a diluted mix of your favourite ballast adhesive.
Here are pictures showing the technique:
This technique is also useful around holes left around feeder-wires. Apply the glue and ballast in these areas so that the more watery mixture of ballast adhesive applied later on will not result in adhesive dripping through to the underside of the layout. It also works well on the track at the ends of Free-mo modules where you have installed PC board end tie plates milled into the shape of railroad ties. This technique prevents ballast from sticking to those places where you don't want it.