Atco Barometer Maintenance

One of the gifts I got for Christmas this year was this German-made Atco barometer.  Although I don’t recall talking about it, I guess I mentioned liking it to my father-in-law a while ago when I saw it in his attic.  He remembered my interest in it and decided to gift it to me this year.  His father gave it to him in the mid-1950s - it was a souvenir they picked up on a trip to Virginia Beach.  He wasn’t sure if the barometer still worked but remembered his father saying it was pretty good quality.  

I looked up the local pressure and saw that the unit was reading way too high.  While I was turning the altitude adjustment screw in the back I noticed the needle was very “hitch-y” - it was only by tapping on the glass while turning the screw could I get the needle where it needed to be.  Even then the barometer only tracked as pressure changed it I rapped the front of the unit once in a while.

I had never done maintenance on an aneroid barometer before so success wasn’t really certain, but the Internet says they occasionally (rarely, but still…) need to be oiled and, besides, this one had a couple of tiny dead bugs trapped inside - it was really just a matter of time before their carcasses gummed up the works in a way that wasn’t easily addressed.  The first step was to make sure I wasn’t about to destroy a rare antique.  A brief check of eBay said I had no worries on that score, but I still needed to be super careful that I didn’t mess up a six-decade-old happy memory.

I removed and cleaned the glass, bid farewell to the dead bugs and their ghosts, then carefully applied machine oil with a sewing needle to the mechanisms it made sense to oil (one of the movements was noticeably squeaky).  I did not clean the brightwork because I like the patina on this thing.  After reassembly I moved the altitude adjustment around a bit to work the oil in.

The barometer is not nearly as hitch-y as it was and it seems to track pretty well.  Siri tells me it is 30.49 inHg, and this unit is reading 30.48 inHg, but the real test will be seeing its behavior during the next storm.  Regardless, it looks cool in its cubby in my new desk next to the Newton Thermometer, so there is where it will stay.

Thank’s for the gift, dad-in-law!