Member Barn Owl shows how to use a 40 caliber shell to fix your broken climate unit knobs.

Barn Owl »

I had one of my climate control knobs break at the mounting base and I was able to make a quick permanent repair of it. In addition to the broken knob I noticed that the other two were cracked and would fail eventually so I modified them all. The knob’s base is an exact fit for a S&W40 caliber spent casing end. I marked the case and then cut it with a hack saw. Slide the brass band over the knobs base and the repair is better than new. The fit is so perfect that no glue is needed. I am attaching a photo to show the repair. I think the photo will do a much better job at explaining this.

npharper »

I had the same problem. I did basically the same repair, too, only I used small zip ties and superglue in place of the sawed casings. They seem solid.

Volvo 850 Climate control knob repair.

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Last Updated on June 22, 2026