Applying Ballast
by Chuck Theidel and Vincent Peri
So your just ballasted road bed has clumps in it that makes it look like the surface of the moon. What happened? You sprayed diluted white glue onto dry ballast.
If you dribble water onto dry, loose ballast, it will crater or clump up because of the water’s natural surface tension. The surface tension causes the water to form droplets that cannot penetrate between individual grains of ballast. You need to break the surface tension by adding a few drops of dish washing liquid or alcohol to the water. Spray this solution over the ballast (which you’ve just put on the track) before you apply the glue.
Another option would be to pre-moisten the ballast before you spread it to increase the capillary action, allowing the glue solution to wick throughout.
I find it best to work in one foot sections, using a spoon as a trowel to distribute the pre-moistened ballast. Use a butter knife to smooth out the beveled edges along the roadbed.
Warning: Be careful around turnouts or else excess ballast will freeze up the swing arms of the mechanism. I squirt a little light-weight, plastic-compatible oil around these moving portions of the switch as it repels the watery adhesive.