Hey Haarlem, Let's keep it in English and I will not try to hijack like most of the guys here free wood is good wood, but hard to get by in residential area's like ours. When ever I see tree service pulling down trees I ask politely and they never refuse unless it's a tree with infectious bugs. Cool to see that there are more like me around here below sea level And on the original thread, ceiling fans are likely most effective since hot air rises but I know few "cool" ceiling fans.
If you ever get a new chain you can practice with the depth adjustment like Oldman47 mentioned above, essentially backing it out until the file only touches the tooth for a pass/two. Now if you rock a chain you have to go deeper but I've never felt the need to make a damaged chain perfect - you can cut pretty well for several sharpenings until the tooth is filed back to ready to break - save those for stump cuts