I'm new to model railroad, but have been doing electrical and electronic soldering work for a very long time. Solder should not be applied to the tip of the iron. It should be applied to the material. Thus you are certain that the items to be soldered are at a sufficient temperature to ensure that the solder flows properly into the joint. Applying solder the to tip of the iron gives the appearance that the solder has flowed, but in fact it is only on the surface which can result in a much weaker joint. Otherwise, great content.