Yes, you should apply the Timbor before staining. You should clean the logs before applying the Timbor by Osborne brushing it to remove smudge marks and splinters and then giving it a light wash to remove dust, dirt and pollen. I prefer Life Line Stain from Perma Chink. It is made for log homes and will put up with all of the movement of the logs expanding and contracting. No matter what stain you use, you MUST keep up on the maintenance every 3 to 4 years. More on the sides that are hit heavier by weather and sun. Call Dave at 800-564-2987 for more help and the materials you will need for this project. He also has other types of stain that he can recommend.