I do have three guitars that are not in a case -- I just don't have a case for them. Two are on stands in the dining room and one is in the living room.
The two in the dining room are
a 1965/1967 Epiphone Caballero (the year is unclear since Gibson in that timeframe used a lot of serial numbers twice) and
a 1949 Tellson 10 (a German guitar my dad once played). This one is equipped with Thomastik-Infeld Jazz Swing JST 12 strings and holds the tuning remarkably well.
My third guitar is by a somewhat obscure manufacturer "Weller" that I have bought 2011 in an ebay auction to practise until I have the money to buy what I really want. This guitar I have to retune quite often, but I guess this is the guitar and the strings, D'Addario flat wounds .012.

Over here strings don't get yucky in the open. But I need to dust the guitars every now and then. (I use a vacuum cleaner with a brush that has very soft bristles.) Sometimes I clean them with a damp soft cloth.


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