Sharon, this is a long term project. It is mostly for education. My Singer collection (there are only a few Singers in that group) is my "personal" collection. The others are for the Museum. They are mostly top clamp machines or the older style where the foot goes directly on the bar instead of the adapter going on the bar and the foot to the adapter.
The true goal is the attachments. Detailed measurements of what each machine takes (I think I'm up to near 20 variations). And also shuttles/bobbins. A resource for those with machines so they can more easily figure out what will fit it.
For the collection- it's "High Arm" style machines, so late 1800's to mid 1940's.
I wanted one machine for each of the 12 Boye shuttle styles (still missing one). Boye researched machines and came up with these 12 to fit most US made machines available at the time (early 1900's). It does not include them ALL, only the more common. Though some of them went out of business around the same time frame
Older round bobbin machines
3/4 size machines of the same time period.
Chain Stitch machines of the same time period.
Post WW2 Japanese made "dash board" machines - just because they look so neat!
As to sewing, I like sewing more than I like sewing machines, so I make sure to find plenty of time for that! However most of the machines I use regularly aren't super old.