The 20mm bottles she uses don't fit any of her racks so I made her one from an old table leg.
This is now my third.
Step 1: What I Used
22mm wood bit
Drill press with 2 axis vice
Step 2: Marking
On this one I worked out I could fit eight bottles
Step 3: Drilling
Step 4: Broke It
Step 5: Finishing Off
You could put a soft material underneath to stop scratches.
The other two I made were sanded the I applied beeswax to them.