Go over your track and turnouts with an NMRA standards gauge
Check all the joints for kinks or one rail higher than the other - run your finger over the joint.
Make sure all turnouts (other track) are flat.
Check the wheels on engines and cars with the NMRA standards gauge.
Do not move on to ballasting until the track and trains work flawlessly.
Good luck
Paul
Do I understand correctly that you are using Bachmann's EZ Track, the stuff with the roadbed attached?
This should make it much more difficult to get lousy trackwork. Do what Paul says, for starters, and look at where and how your trains are derailing.
Is it always the same cars / locos, or always in the same spots?
I forget -- what equipment are you running. If you're trying to run 3 axle diesels or anything bigger than a 2-8-2 steam loco on an 18" curve, that may be the source of your difficulties as well.
Connecticut Valley Railroad A Branch of the New York, New Haven, and Hartford
"If you think you can do a thing or think you can't do a thing, you're right." -- Henry Ford
Your track can have dips that effect only one rail - even EZ-Track. Most 4 axle diesels will go over them with no problem but 6 or 8 axle units, steamers and long rolling stock won't. You can find these places by setting a 3 foot level on the track and looking along it. Any place where one rails dips or rises will be visible.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam