Those darned gutters and their downspouts. Probably metric.

You know about the epoxy option. If you can open up the rotted hollow part by cutting out a door in the solid outer part of the log, the rotted part can be cleaned out, soaked with epoxy to solidify anything that is spongy, and then solid wood and epoxy\sawdust filled. The log can be stabilized and the "door" can be glued (epoxied) back in place.

Maybe not the cheapest solution, but a solid and permanent solution. Whatever the epoxy touches will be permanent and, if done right, close to invisible.

It worked for my "Dirty Rotten Ridgepole".

I got the idea from the Smith's Rot Doctor website. Depending on your schedule, I might be able to stop in for a week to help.

PS... It's not invisible, but it's easy to make it hard to see. I know it is "possible" to replace part of a log, but I know it is not fun.

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