I wanted to build a better-looking dice tray, with some stat-tracking capabilities. I'd seen a dice box with spell abacus and liked the idea, but I wanted something that could replace my paper scratchings entirely. So it needs to be persistent from week to week, and it needs to track all limited-use class abilities (not just spells). It also needs to support playing in multiple campaigns at once. I decided on a similar abacus design attached to my dice-rolling tray, but with modular, swappable abaci (one for each character I'm playing). The dice tray will fold into a box, with room for a spell card book, dice, pens, pencils, etc, and a rail for commonly used dice right on the tray edge.
Here's how the top tray (the more interesting part) turned out:
At the top are failed/successful death saves, then spells, then other actions (a war priest's bonus attacks in this case), and at the bottom are actions that reset on a short rest (channel divinity and a Mark of the Sentinel shield power). I put the short rest things at the bottom to make resetting easier.
The die rolling surface is a thin layer of cork covered with an ultrasuede; it makes for a very pleasant, quiet rolling experience with heavy metal dice and looks pretty sharp. Ultrasuede is pretty stretchy and a pain to cut cleanly, though.
The abacus can be removed and swapped out (I made 3), and each one opens up so you can change out the beads. A spell card book stows away in the rolling area during storage and transport:
The base is just a large cork-lined storage area; I may add some dividers to it later, or it can act as a second rolling tray in a pinch:
The box closes with magnets:
The top rail of the rolling tray where the dice sit was made of two 1/2" boards, one with the 7/8" holes drilled in it and the other solid. Glue them together and you have a nice rail for the dice to sit in.
The abaci are 1/4" slatting cut to length and then holes drilled halfway in; 1/8" dowels go into the holes. A drill press makes this a lot easier than trying to free-hand it.
Vertical slots were hand-chiseled into the top rail and near edge of the box for the abacus to slide into:
There were some things that didn't pan out. I was going to have a couple of hex dice storage areas with a mini storage in the bottom cork part, but it proved too bulky and kind of pointless after I got it set in:
I also wanted to mount these rings at the top left corner of the dice tray (you can see the top rail I've carved out space underneath to the left), but they're not quite narrow enough. I'm still thinking about ideas for an integrated HP tracker in that space:
All told it was about 8 hours of work, but a drill press saved a ton of time there.
PDF of the dimensions, though I tweaked it some on the fly.