We built our log home 13 years ago. Have done routine maintenance every 3 years. Always washed the logs with a power washer and let it dry for at least a month before staining. The last time we used a power washer the psi was higher than we realized. It chipped some of the stain from the logs. It is not bad but we are concerned it will not blend when we start staining. Can we stain over the area the power washer stripped or do we need to sand the area first. If so, what type of sander do we