I have a 40 year old cabin in Denver Colorado that hasn’t seen much maintenance (there are some traces of a previous coating, maybe paint). It is gray, but the logs are good and solid (6” D logs with cement chinking). My first question is, does it hurt to just leave the exterior the way it is? It hasn’t degenerated much in the last 20 years, does it hurt to leave it another 10-20 years without refinishing? If I do decide to do freshen it up, what would you recommend? Is corn cob blasting