There are many beading trays on the market, usually made of flimsy vacuum formed plastic, they are relatively expensive, and never quite exactly what you want.
You will need:
1. A router and 12mm core box (hemispherical) cutter.
2. Non-slip routing mat.
3. A piece of 18mm Medium Density Fiberboard (MDF).
4. Sandpaper, Optionally a sanding machine.
5. Chisel, Bradawl, Screwdriver
6. Varnish and Brush.
Step 1: Set Up Your Router.
I used a home made jig to rout the semicircular groves in the MDF. This is simply a piece of wood, with two pieces of mild steel drilled and tapped to accept a couple of threaded knobs, allowing it to be clamped to the rods which normally support the standard fence.. This has a hole drilled down the centre which enables it to be screwed to the surface of the MDF.
I have used a non slip router mat to hold the workpiece steady.
Some routers come with an attachment for this.
The center picture show the router screwed to the MDF ready to go.
I have attached a workshop vacuum to extract the dust.
You should wear appropriate Personal Protection Equipment and read the manuals for your tools. Safety glasses should be worn at all times. This is not intended to be a tutorial on how to use a router. If you do not already know this seek advice from someone who does.
Medium Density Fiberboard should be machined in a well ventilated area as the dust can cause respiratory problems. Use a dust mask and/or dust extractor.
Step 2: Rout Grooves.
I have opted for four, but it is up to you.
Step 3: Rout Wells to Hold Beads.
I reattatched the standard fence to the router for this, and used the same cutter.
After roughly routing, I tidied up the wells with a sharp chisel and sandpaper.
Step 4: Sand
I sanded off the pencil marks and radiused the corners with a random orbit sander. You can do this by hand.
Step 5: Finish
I applied two coats of quick drying varnish, with a light sand between coats
Step 6: Enhancement.
In this variation I cut three holes with a holesaw, then used the router to chamfer these off. These holes were the right size to fit interchangable china sauce dishes from an oriental supermarket.
It is also a bit smaller to fit into my partner's crate of beading stuff.
You can back the board with baize, self adhesive felt pads, or rubber feet.