I have a small and slowly growing collection of 78 rpm records. I'm fairly conservative about buying new ones, both because I'm cheap and because there aren't that many artists that I know and want to collect from that era. I'm also not really looking for value necessarily, but things I enjoy listening to.
In any case, I'm up to about 130 records, and they've overflowing the shelf I'd taken in our regular LP vinyl collection, which could also use the extra space. Another complication is that we don't have much space in the house for more furniture. The obvious solution (for me, anyway) is a small cabinet dedicated to 10" records, both making space for 78s and preventing it from being taken over by vinyl.
To keep the cost down, I decided to use birch plywood for the case, 3/4" for strength since that shellac gets heavy. The design was inspired by some tapered walnut legs that my dad gave me years ago. I have no idea where they came from, but they seemed like they'd fit in with some of the mid-century modern pieces we have.
Measuring out 11" shelves for enough height, I cut the initial pieces to size and planned out dadoes for shelf and dividers. The front edges got a 1/2" rounded inner corner on the router table. Everything will just be glued so there won't be any visible fasteners, but the interlocking center pieces will add a lot of structure.
Here I'm preparing for the glue-up using these picture frame corner clamps to hold and align the front edges and miters, along with a few long bar clamps around the whole thing.
After that cured for a day I made a quick sled for cutting miter key slots in the corners. I wanted both the extra strength and some contrast to the sea of light wood.
It's not exactly a production-quality jig, but did the job just fine and kept them consistent, using the fence as a stop. I cut slots for double-kerf thickness keys on the outside and a thin one on the center.
With the keys in place and trimmed, everything got a final sanding and finished it with 3 coats of clear polyurethane. The legs are mounted on some maple pieces I had, cut to a 15° angle and installed with lag screws that fit the existing threaded holes.
And the cabinet installed in place with all of my current 10" 78s. Small felt pads cushion the feet and help fine-tune the leveling on our old floors.
I measured about 10 records per inch, in standard paper sleeves, so the cabinet can theoretically hold about 400, but I have a few albums that take up more space, plus dividers. In any case, I can easily triple the size of my current collection and still fit just fine.